This study aimed to investigate the current management of endometrial hyperplasia (EH) in Korea.

This was an electronic survey, which included 40 questions, that was distributed to the members of the Korean Gynecologic Oncology Group in 2014.

In total, 50 (69%) of 72 members responded to the survey. The oral progestogens were the most popular choices for managing EH without atypia (simple hyperplasia(SH), 64%; complex hyperplasia (CH), 52%). In the case of CH with atypia, most of the gynecologist respondents would perform hysterectomy (95.9%). For fertility preservation, the oral progestogens were the most popular choices (SH, 75.5%; CH, 56.3%), followed by the levonorgestrel-releasing intrauterine system (LNG-IUS). More than 70% of the respondents reported use of dilatation and curettage as a follow-up method.

Our survey results show that most of Korean gynecologic oncologists still prefer oral progestogens for conservative management of EH, notwithstanding the many successful reports on the LNG-IUS. As a follow-up evaluation method, dilatation and curettage is mostly used. To identify the optimum therapy, a randomized controlled trial comparing the LNG-IUS with continuous oral progestogens is required. Furthermore, a large-scale prospective study to confirm the most reliable technique for follow-up evaluation is necessary.

For select women with early endometrial cancer, particularly nulliparous women, nonsurgical options may be considered. There is increasing experience using progestogens, but little is known about the long-term outcomes and safety of such treatment.

To present the cancer and pregnancy outcomes of women with greater than five years follow-up after progestogen treatment for early endometrial cancer.

Ten women who underwent greater than six months of continuous progestogen therapy for early endometrial cancer were included in the study. All were managed by a gynaecological oncologist at a major tertiary centre in Melbourne, Australia. The histology of each subsequent curette was recorded, as was the timing and histology of hysterectomy (if relevant), and the results of any subsequent pregnancies.

All ten women showed histological regression of cancer with no cases of recurrence on follow-up curette. Four of ten women have undergone hysterectomy with one case of occult disease persistence in a woman noncompliant with therapy. The mean follow-up time was 89 months (range 62-142 months), there were no deaths and no woman was lost to follow-up. All four women attempting pregnancy were successful. There were eight pregnancies and five live births.

This form of treatment appears to be successful and safe in the long term with good pregnancy outcomes. However, it is not standard and should be supervised in a specialised gynaecological oncology unit.

In the United States, endometrial cancer is the most commonly diagnosed cancer of the female reproductive system. Strategies to sensitively and accurately diagnose premalignant endometrial lesions are sorely needed. We reviewed studies pertaining to the diagnostic challenges of endometrial precancers, their predictive value, and evidence to support management strategies. Currently, two diagnostic schemas are in use: the four-class 1994 World Health Organization hyperplasia system, based on morphologic features of architectural complexity and nuclear atypia and, more recently, the two-class endometrial intraepithelial neoplasia system, which is quantitative. Diagnosis should use criteria and terminology that distinguish between clinicopathologic entities that can be managed differently. In some instances, such as for women with hereditary nonpolyposis colon cancer, biomarkers may aid in diagnosis, but the clinical utility of biomarkers has yet to be determined. Total hysterectomy is curative for atypical endometrial hyperplasia or endometrial intraepithelial neoplasia, and provides a definitive standard for assessment of a concurrent carcinoma, when clinically appropriate. If hysterectomy is performed for atypical endometrial hyperplasia or endometrial intraepithelial neoplasia, then intraoperative assessment of the uterine specimen for occult carcinoma is desirable, but optional. Nonsurgical management may be appropriate for patients who wish to preserve fertility or those for whom surgery is not a viable option. Treatment with progestin therapy may provide a safe alternative to hysterectomy; however, clinical trials of hormonal therapies for atypical endometrial hyperplasia or endometrial intraepithelial neoplasia have not yet established a standard regimen. Future studies will need to determine the optimal nonsurgical management of atypical endometrial hyperplasia or endometrial intraepithelial neoplasia, standardizing agent, dose, schedule, clinical outcomes, and appropriate follow-up.

Immunohistochemical markers to assist in the diagnosis and classification of hyperplastic endometrial epithelial proliferations would be of diagnostic use. To examine the possible use of PAX2 as a marker of hyperplastic endometrium, cases of normal endometrium, simple and complex hyperplasia without atypia, atypical hyperplasia, and International Federation of Gynecology and Obstetrics (FIGO) grade 1 endometrioid carcinomas were stained for PAX2. Two hundred and six endometrial samples were available for interpretation of PAX2 staining. The percentage of cases with complete PAX2 loss (0% of cells staining) increased with increasing severity of hyperplasia: 0% of normal proliferative and secretory endometrium (n=28), 17.4% of simple hyperplasia (n=23), 59.0% of complex hyperplasia (n=83), 74.1% of atypical hyperplasia (n=54), and 73.3% of FIGO grade 1 endometrioid cancers (n=15). Partial loss of PAX2 expression did occur in normal endometrium (17.9%) but in smaller proportions of tissue and was less frequent than in simple hyperplasia (47.8% with partial loss), complex hyperplasia (32.5%), atypical hyperplasia (22.2%), and FIGO grade 1 carcinomas (20.0%). Uniform PAX2 expression was rare in complex (8.4%) and atypical hyperplasia (3.7%) and carcinoma (6.7%). When evaluating loss of PAX2 in histologically normal endometrium adjacent to lesional endometrium in a given case, statistically significant differences in staining were observed for simple hyperplasia (P=0.011), complex hyperplasia (P<0.001), atypical hyperplasia (P<0.001), and FIGO grade 1 endometrioid cancer (P=0.003). In summary, PAX2 loss seems to occur early in the development of endometrial precancers and may prove useful in some settings as a diagnostic marker in determining normal endometrium from complex and atypical hyperplasia and low-grade carcinomas. However, it is not useful in distinguishing between these diagnostic categories.

The objective of the present study was to evaluate whether nuclear atypia or PTEN-loss in endometrial intraepithelial neoplasia (EIN), could help to predict in endometrial curettage material, the prevalence of concurrent carcinoma in hysterectomy specimens.

This retrospective single-institution study included women who were diagnosed with endometrial hyperplasia (simple or complex) and underwent hysterectomy within 12weeks from the initial diagnosis without interval treatment. All endometrial curettage slides were reviewed by three experienced pathologists and only cases that fulfilled the criteria of EIN were used for further analysis. For each case, the nuclear atypia and the immunohistochemically detected expression of PTEN were evaluated. The hysterectomy slides were also reviewed and the findings were used in the subsequent analysis.

Out of 83 cases that were enrolled in the study, 33 (39.76%), had a concurrent endometrial carcinoma. Nuclear atypia in EIN cases with a final histology of endometrial cancer was found in 31 out of 33 cases (93.94%) but only in 27 out of 50 benign cases (54%). There was no PTEN-loss in 8 out of 33 EIN cases (24.24%) that proved to be cancer and 22 out of 50 EIN cases (44%) that proved to be benign. Either atypia or PTEN-loss or both were found in 33/33 (100%) cancer cases and in 39/50 (78%) benign cases; this difference was statistically significant (Fisher exact test, p < 0.05).

PTEN-loss, as an independent variable, was not found to be a predictor of endometrial cancer in the final histology. However, biopsies presented with EIN, featuring nuclear atypia and recognized as PTEN-null are more likely to be finally diagnosed with endometrial cancer.

Limited data exist to inform clinicians and patients as to the likelihood of long-term endometrial hyperplasia response to progestin therapy, especially for atypical hyperplasia. We evaluated women with complex and atypical endometrial hyperplasia, comparing those prescribed progestin with those not prescribed progestin.

This retrospective cohort study was conducted in 1985-2005 among women aged 18-88 years at an integrated health plan in Washington State. Women were ineligible if they achieved an outcome (endometrial carcinoma, hysterectomy, or both) within 8 weeks of hyperplasia diagnosis. Exposure was progestin use for at least 14 days by duration and recency. Outcomes included rate of 1) endometrial carcinoma, 2) hysterectomy, or 3) both. Analyses performed included Kaplan-Meier, incident rate ratios, and Cox proportional hazard ratios.

One thousand four hundred forty-three eligible women were identified. One thousand two hundred one had complex (n=164 no progestin) and 242 had atypical (n=62 no progestin) hyperplasia. During follow-up, a median of 5.3 years (range 8 weeks to 20.8 years), 71 women were diagnosed with endometrial carcinoma (35 complex, 36 atypia) and 323 underwent hysterectomy (216 complex, 107 atypia). Among women with complex and atypical hyperplasia, rates of endometrial carcinoma among progestin users were 3.6 and 20.5 per 1,000 woman-years, respectively (compared with women who did not use progestin, 10.8 and 101.4). Among women with complex and atypical hyperplasia, rates of hysterectomy among progestin users were 23.3 and 61.4 per 1,000 woman-years, respectively (compared with women who did not use progestin, 55.1 and 297.3).

Endometrial carcinoma risk is diminished approximately threefold to fivefold in women diagnosed with complex or atypical endometrial hyperplasia and dispensed progestin; hysterectomy risk is also decreased.

II.

Our objectives were (1) to review the rate of concurrent endometrial cancer in patients with a preoperative diagnosis of atypical endometrial hyperplasia (AEH); (2) to determine the proportion of patients with concurrent endometrial cancer who have high-risk disease; and (3) to re-evaluate our surgical management of AEH.

We performed a retrospective chart review of all patients who had surgery on the basis of a preoperative diagnosis of atypical endometrial hyperplasia between January 2001 and December 2006. Demographic data, the method of preoperative diagnosis, postoperative grade of tumour, and other postoperative findings were recorded. When applicable, this included cancer stage, lymph node status, and presence of lymphovascular space invasion. In postoperative review, patients were considered to be high risk if they had disease beyond the uterus or a combination of other risk factors.

Of 70 patients, 25 (35.7%) were found to have concurrent endometrial cancer. This was higher than the commonly accepted rate of 25% (P = 0.03). Of the 25 patients upgraded, 4 (16%) had high-risk cancer on final pathologic evaluation.

Simple hysterectomy in women with AEH may result in inadequate surgical management. Simple methods are required to identify patients with a preoperative diagnosis of AEH who may harbour significant cancers.

The authors sought to test the hypothesis that characteristics and exposures which influence the balance of estrogen and progesterone bear on the incidence of endometrial hyperplasia (EH), a noninvasive proliferation of the lining of the uterus. Cases included all female members of Group Health (Washington State) who were diagnosed with complex EH or EH with atypia during the period 1985-2003 and whose diagnoses were confirmed in a pathology review (n = 446). Controls were selected randomly from Group Health membership files and were matched to the cases by age and enrollment status at the reference date. An increased risk of EH was associated with increasing body mass index and nulliparity. There was a suggestion of a decreased risk of EH with atypia among current smokers. No association with diabetes or hypertension was found. The risk factors observed to be associated with EH in this study are similar to those associated with endometrial cancer. Whether these risk factors predispose women to cancer simply by increasing EH incidence or continue to augment cancer risk even after EH is present is currently unknown.

Current World Health Organization classification of endometrial hyperplasia is problematic because of poor diagnostic reproducibility. We sought to determine factors that cause diagnostic disagreement in a review of 2601 endometrial specimens. Blinded random specimens of normal endometrium, hyperplasias, and carcinoma were reviewed by 2 pathologists, with review by a third pathologist in cases with disagreement. All cases of endometrial hyperplasia or carcinoma were scored for degree of glandular crowding, architectural complexity, and cytologic atypia. Sample adequacy, hyperplasia volume, presence of metaplasia, or endometrial polyp were also scored. The overall kappa for agreement was 0.71, with a lower kappa of 0.36 when cases called "no hyperplasia" were excluded. The percent specific agreement was 90.3% for no hyperplasia, 31.1% for simple hyperplasia, 51.1% for complex hyperplasia, 49.8% for atypical hyperplasia, and 57.5% for adenocarcinoma. Cases categorized as "low volume hyperplasia" had more diagnostic disagreement than "high volume," (62% vs. 39%, P=0.003). Similarly, cases called "scant" had more diagnostic disagreement than "not scant" (65% vs. 57%, P=0.013). The histologic feature associated with the most diagnostic disagreement was cytologic atypia (P<0.0001). Architectural crowding, architectural complexity, or the presence of a polyp were all associated with diagnostic disagreement (P<0.0001). High diagnostic disagreement in endometrial hyperplasia is related to both sample adequacy and interpretation of histologic features present. Although obtaining additional tissue may increase diagnostic reproducibility, differences in interpretation of key histologic features like cytologic atypia remain major factors contributing to diagnostic disagreement.

In this article, the authors briefly review the historical evolution of the various putative precursor lesions for Type II endometrial cancers, with an emphasis on the newly defined "Endometrial Glandular Dysplasia (EmGD)". The evidentiary basis for delineating serous EmGD as the most probable precursor lesions to endometrial serous carcinoma is reviewed in detail. An argument is advanced for the discontinuation of the term serous "endometrial intraepithelial carcinoma (EIC)" as a descriptor for a supposedly intraepithelial, precancerous lesion. Preliminary evidence is also presented that suggests that there is a morphologically recognizable "clear cell EmGD" that probably represents a precancerous lesion to endometrial clear cell carcinomas.

Endometrial cancer (EC) is the most common malignancy of the female genital tract in the western world. Conceptually, a dualistic model of endometrial carcinogenesis exists for sporadic EC, based on molecular findings with a good correlation to the morphologic phenotype and clinical behavior. Type 1 endometrial carcinoma represents an estrogen-related tumor, which usually arises in the setting of endometrial hyperplasia, has endometrioid histology with low grade, and tends to be biologically indolent. Grade 3 endometrioid cancers, which constitute a minority of EC, also behave aggressively. The type 2 cancers are not estrogen-driven and have a higher grade, various histologies, particularly serous carcinomas and clear-cell carcinomas, and a poorer prognosis. The diagnostic criteria of endometrial hyperplasia, endometrial in situ carcinoma, and of the different histologic types of EC, according to the most recent World Health Organization classification, are given in detail. In addition, the risk of progression of endometrial hyperplasia into endometrioid type EC and their treatment modalities are discussed. Endometrial pathologies in patients with breast cancer, receiving tamoxifen, and women affected by hereditary nonpolyposis colorectal cancer syndrome are described, including their pathogenetic aspects. Finally, a short practical description for the handling of surgical specimens from fractional curetting and hysterctomies is given.

Endometrial hyperplasia is found in 2% to 10% of women with abnormal uterine bleeding (AUB). Up to 43% of patients with cytologic atypia harbor coexisting adenocarcinoma, and approximately 20% to 52% of atypical hyperplasias, if untreated, progress to cancer. The objective of this study was to estimate the incidence of atypical endometrial hyperplasia encountered during routine resectoscopic surgery in women with AUB and to evaluate the role of resectoscopic surgery in the management of women with AUB and atypical endometrial hyperplasia who refused and/or were at high risk for hysterectomy.

Prospective cohort study (Canadian Task Force classification II-3).

University-affiliated teaching hospital.

From January 1990 through December 2005, the senior author (GAV) performed primary resectoscopic surgery in 3401 women with AUB. Among these, there were 22 women with atypical (17 complex, 5 simple) endometrial hyperplasia.

All women underwent hysteroscopic evaluation and partial (n = 3) or complete (n = 19) endometrial electrocoagulation and/or resection. Subsequently, 6 women had hysterectomy and bilateral salpingo-oophorectomy (BSO).

The median (range) for age, parity, and body mass index were 55 years (24-78 years), 2 (0-4), and 30.1 kg/m2 (22.5-52.2 kg/m2), respectively. Among the 3401 women, there were 22 cases of atypical endometrial hyperplasia, 12 of which were incidentally diagnosed at the time of hysteroscopy (complex 10, simple 2, incidence 0.35%). After hysteroscopic diagnosis or confirmation of diagnosis, 6 women underwent hysterectomy and BSO. Of the remaining 16 women, followed for a median of 5 years (range 1.5-12 years), 1 was lost to follow-up, 1 had only a biopsy to preserve fertility, 1 died from lung cancer after 4 years, and 1 died from colon cancer after 5 years. One patient developed endometrial cancer after 10.5 years with postmenopausal bleeding. She remains alive and well 3.5 years after hysterectomy and BSO. The remaining 11 patients are amenorrheic at a median follow-up of 6 years (range 1.5-12 years).

Resectoscopic surgery in 3391 women with AUB detected 12 incidental cases of atypical endometrial hyperplasia (incidence 0.35%). Skillful resectoscopic surgery may be an alternative to hysterectomy in women with AUB and atypical endometrial hyperplasia, who refuse or are at high-risk for hysterectomy and who are compliant with regular and long-term follow-up.

Most gynecologists determine therapy based on current International Society of Gynecologic Pathologists (ISGP)/World Health Organization classification of endometrial hyperplasia, the reproducibility of which has been questioned. The Gynecologic Oncology Group (GOG) initiated a protocol to assess the efficacy of hormonal therapy of atypical endometrial hyperplasia (AEH). Primary goals of the first phase (Part A) were to prospectively determine reproducibility of referring institution's pathologist's diagnosis of AEH by a panel of 3 gynecologic pathologists and to determine reproducibility of diagnoses by panel members.

Three hundred six women were entered on this protocol with a referring institution's pathologist diagnosis of AEH based on biopsy or curettage. Available slides were assessed independently and interpreted by each of a panel of 3 gynecologic pathologists who used International Society of Gynecologic Pathologists (ISGP)/World Health Organization criteria. The majority diagnosis was based on diagnostic concordance by at least 2 of the 3 panelists.

The referring institution's pathologist's diagnosis of AEH was supported by the majority of the panel in only 38% of cases. Overall kappa value for the panel diagnosis of AEH was 0.28. The majority diagnosis was adenocarcinoma in 29%, cycling endometrium in 7%, and nonatypical hyperplasia in 18% of cases. Unanimous agreement for any diagnosis was reached among all 3 of the panel in 40% of cases. For the panel, paired kappa values for any diagnosis ranged 0.34-0.43, with an overall kappa value of 0.40.

Reproducibility of referring institution's pathologists' diagnosis of AEH by a panel of gynecologic pathologists is poor. Both underestimation and overestimation of the severity of the lesion are very common. The level of reproducibility among subspecialist panel members for diagnosis of AEH in these specimens also is poor. Better criteria and better sampling are needed to improve reproducibility of this diagnosis, particularly if it is to be used for clinical decisions.

Because cellular atypia is often limited in endometrial hyperplasia and well-differentiated endometrial adenocarcinoma (WHO Grade 1 adenocarcinoma), diagnostic criteria for endometrial cytology have not been fully established. New diagnostic criteria based on the composition and architecture of tissue fragments (cytoarchitecture) in the smears were used in the present study. Cytologic features are of less importance because the distinction between endometrial hyperplasia and Grade 1 adenocarcinoma relies more on architectural features than cellular changes. Cell clumps of various size are usually collected abundantly with cytologic material using a disposable scraping device and it was noticed that those cell clumps reflected the histologic architecture. The purpose of the current study was to determine the form of the cytoarchitecture that reflects the histologic structure and to examine the cellular features in endometrial hyperplasia and Grade 1 adenocarcinoma.

The frequency of each type of cell clump (tube or sheet-shaped pattern, dilated or branched pattern, irregular protrusion, and papillotubular pattern) were obtained from 49 cases of normal proliferative endometrium (NPE) (patient age range, 28-51 yrs; average age, 39.9 yrs), 63 cases of endometrial hyperplasia without atypia (EH) (patient age range, 35-65 yrs; average age, 47.7 yrs), 13 cases of endometrial hyperplasia with atypia (AEH) (patient age range 47-65 yrs; average age, 53.8 yrs), and 49 cases of Grade 1 adenocarcinoma (patient age range, 42-73 yrs; average age, 58.9 yrs).

Certain characteristics of the cytoarchitecture were observed. In the NPE, cell clumps with a tube or sheet-shaped pattern were found in 97.5% of cases. In the EH, cell clumps with a dilated or branched pattern were found in 34.9% of cases. In the Grade 1 adenocarcinoma, cell clumps with irregular protrusions were found in 61.8% cases, whereas a papillotubular pattern was present in 29.7% of cases.

The results of the current study revealed that cytoarchitectural criteria appear to be more useful for the cytologic assessment of endometrial lesions, especially for the diagnosis of endometrial hyperplasia and Grade 1 adenocarcinoma.

Adenocarcinoma of the endometrium is the most common gynecologic malignancy in the United States, accounting for approximately 36,000 diagnoses of invasive carcinoma annually. The most common histologic type, endometrioid adenocarcinoma (EC), accounts for 75-80% of patients. The objective of this work was to estimate the prevalence of concurrent carcinoma in women with a biopsy diagnosis of the precursor lesion, atypical endometrial hyperplasia (AEH).

This prospective cohort study included women who had a community diagnosis of AEH. Diagnostic biopsy specimens were reviewed independently by three gynecologic pathologists who used International Society of Gynecologic Pathologists/World Health Organization criteria. Study participants underwent hysterectomy within 12 weeks of entry onto protocol without interval treatment. The hysterectomy slides also were reviewed by the study pathologists, and their findings were used in the subsequent analyses.

Between November 1998 and June 2003, 306 women were enrolled on the study. Of these, 17 women were not included in the analysis: Two patients had unreadable slides because of poor processing or insufficient tissue, 2 patients had only slides that were not endometrial, the slides for 5 patients were not available for review, and 8 of the hysterectomy specimens were excluded because they showed evidence of interval intervention, either progestin effect or ablation. In total, 289 patients were included in the current analysis. The study panel review of the AEH biopsy specimens was interpreted as follows: 74 of 289 specimens (25.6%) were diagnosed as less than AEH, 115 of 289 specimens (39.8%) were diagnosed as AEH, and 84 of 289 specimens (29.1%) were diagnosed as endometrial carcinoma. In 5.5% (16 of 289 specimens), there was no consensus on the biopsy diagnosis. The rate of concurrent endometrial carcinoma for analyzed specimens was 42.6% (123 of 289 specimens). Of these, 30.9% (38 of 123 specimens) were myoinvasive, and 10.6% (13 of 123 specimens) involved the outer 50% of the myometrium. Among the women who had hysterectomy specimens with carcinoma, 14 of 74 women (18.9%) had a study panel biopsy consensus diagnosis of less than AEH, 45 of 115 women (39.1%) had a study panel biopsy consensus diagnosis of AEH, and 54 of 84 women (64.3%) had a study panel diagnosis of carcinoma. Among women who had no consensus in their biopsy diagnosis, 10 of 16 women (62.5%) had carcinoma in their hysterectomy specimens.

The prevalence of endometrial carcinoma in patients who had a community hospital biopsy diagnosis of AEH was high (42.6%). When considering management strategies for women who have a biopsy diagnosis of AEH, clinicians and patients should take into account the considerable rate of concurrent carcinoma.

To identify current management practices and evaluate subsequent outcomes of treatment for women diagnosed with endometrial hyperplasia.

All women with a histological diagnosis of endometrial hyperplasia at the Birmingham Women's Hospital were identified between October 1998 and September 2000. A retrospective case note review was performed for each woman using a standardised data abstraction sheet. Baseline characteristics including clinical presentation and treatment strategy were obtained. Results of subsequent endometrial tissue examinations were used to assess histological response to treatment and the need and indication for hysterectomy was used to assess clinical response.

There were 351 women diagnosed with endometrial hyperplasia during the study period of which 84% presented with symptoms of abnormal uterine bleeding and 54% were postmenopausal. Complex endometrial hyperplasia was the most common diagnosis accounting for 60% of all cases. Eighty percent of women with atypical endometrial hyperplasia were treated by hysterectomy compared with 30% without evidence of cytological atypia (relative hysterectomy rate of 2.6, 95% CI 2.0-3.3). Hysterectomy was avoided in 138/172 (80%, 95% CI 74-86%) women managed conservatively during the study period. Overall 35/108 (36%, 95% CI 27-46%) of women managed conservatively had persistent or progressive disease identified (mean follow up 36 months). 20/143 (14%) women initially diagnosed with endometrial hyperplasia who subsequently underwent hysterectomy were found to have endometrial cancer, the majority of whom had been diagnosed with atypical disease (14/20, 70%).

The majority of women with atypical endometrial hyperplasia were managed by hysterectomy and the substantial risk of diagnostic under-call supports this approach to treatment. In contrast, there is no consensus regarding the initial management of women with endometrial hyperplasia without cytological atypia.

There is controversy regarding the prevalence of underlying endometrial adenocarcinoma among women with a diagnosis of atypical endometrial hyperplasia. This study further defines that risk. At our institution atypical endometrial proliferations non-diagnostic for invasive adenocarcinoma are diagnosed as either atypical endometrial hyperplasia (ATHY) or as an "atypical proliferative lesion of the endometrium, suggestive but not diagnostic of atypical endometrial hyperplasia" (APL). Between 1996 and 2003, these diagnoses were made on either endometrial biopsy or endometrial curettings in 60 women who subsequently received a hysterectomy. Endometrial adenocarcinoma was identified in 48% (29/60) of the hysterectomy specimens. Age and sampling method had no significant impact on the prevalence of adenocarcinoma. Adenocarcinoma was no more likely to be subsequently identified when a woman had a preoperative diagnosis of ATHY (24 of 52, 46%) compared to APL (5 of 8, 63%). In some women with a diagnosis of ATHY a comment was made in the report that "carcinoma cannot be ruled out". These cases had a significantly higher prevalence of underlying adenocarcinoma (16 of 25, 64%) compared to cases of ATHY in which such a comment was not made (8 of 27, 30%) (p = 0.025). In conclusion, there is a high prevalence of underlying endometrial adenocarcinoma among women undergoing hysterectomy for any of atypical endometrial proliferation.

To determine the occult coexistence of endometrial carcinoma in patients with atypical endometrial hyperplasia and to compare histological prognostic factors according to lymph node status in occult endometrial carcinoma.

Two hundred and four patients from two referral centers (during the period 1990-2003) who were operated on within 1 month of endometrial biopsy for symptomatic endometrial hyperplasia without receiving any medical treatment were included retrospectively. Patients having preoperative endometrial biopsy results of concomitant endometrial hyperplasia and carcinoma were excluded from the study. Fifty-six patients having atypia in preoperative biopsy (group I) were compared with 148 patients without atypia (group II). Chi-square and Mann-Whitney U-tests were used for statistical analyses.

No significant difference was observed between the two groups according to age or menopausal status. Patients in group II had significantly higher parity than patients in group I. In group I, 62.5% of the patients had endometrial carcinoma, 21.4% had endometrial hyperplasia, and 16.1% had normal endometrium in hysterectomy specimens. In group II, the percentages were 5.4, 38.5, and 56.1%, respectively. Complete surgical staging was performed in 20 patients. Four patients had metastatic lymph nodes. All of them had grade 2 tumors with lymphovascular space involvement. Three of them had nonendometrioid tumors.

Careful intraoperative and preoperative evaluation of the endometrium must be the sine qua non for patients with atypical endometrial hyperplasia. It is reasonable to do frozen section at the time of hysterectomy for atypical endometrial hyperplasia, and if grade 2/3 of nonendometrioid cancer with lymphovascular space involvement is found, complete surgical staging should be performed.

Hyperplasia of the endometrium is a process characterized by an irregular, noninvasive proliferation of glands with a variable amount of stroma. Precise classification of endometrial hyperplasia in biopsy material is important in order to identify those hyperplasias that are likely to be precursors of endometrial adenocarcinoma. The current World Health Organization (WHO) classification provides a scheme that has become widely accepted, primarily dividing hyperplasias in to those with and those without cytologic atypia while the degree of glandular crowding (simple vs. complex) has secondary importance. A wide variety of other endometrial changes, ranging from artifacts, metaplasias and polyps to well-differentiated adenocarcinoma must be considered in the differential diagnosis. Well-differentiated adenocarcinoma is diagnosed when one of 3 essential criteria is found in biopsy specimens: (1) a confluent gland pattern; (2) an extensive papillary pattern; or (3) a desmoplastic stromal response. Using the WHO classification allows segregation of endometrial hyperplasia into clinically meaningful categories. Strict morphologic criteria also enable separation of hyperplasia from well-differentiated adenocarcinoma.

Endometrial hyperplasia is a precursor to the most common gynecologic cancer diagnosed in women: endometrial cancer of endometrioid histology. It is most often diagnosed in postmenopausal women, but women at any age with unopposed estrogen from any source are at an increased risk for developing endometrial hyperplasia. Hyperplasia with cytologic atypia represents the greatest risk for progression to endometrial carcinoma and the presence of concomitant carcinoma in women with endometrial hyperplasia. Abnormal uterine bleeding is the most common presenting symptom of endometrial hyperplasia. Specific Pap smear findings and endometrial thickness per ultrasound could also suggest the diagnosis. Unopposed estrogen in women taking hormone replacement therapy increases the risk of endometrial hyperplasia. Tamoxifen has demonstrated its efficacy in treating women at risk for breast cancer, but it increases the risk of endometrial hyperplasia. The choice of treatment for endometrial hyperplasia is dependent on patient age, the presence of cytologic atypia, the desire for future childbearing, and surgical risk. Endometrial hyperplasia without atypia responds well to progestins. However, women with atypical hyperplasia should be treated with hysterectomy unless other factors preclude surgery.

Obstetricians & Gynecologists, Family Physicians.

After completion of this article, the reader should be able to describe the definition and classification of endometrial hyperplasia, to outline the clinical features of a patient with endometrial hyperplasia, to point out the natural history of endometrial hyperplasia, and to summarize the diagnostic options for patients with endometrial hyperplasia.

In most cases, the endometrioid adenocarcinoma of the endometrium is preceded by hyperplasia with different risk of progression into carcinoma. The original histologic slides from 560 consecutive cases with complex and atypical hyperplasia were re-examined to assess the interobserver-correlation. The hyperplasias were analyzed separately for their likelihood of progression to carcinoma in patients with and without progestogen hormonal therapy. In all cases, a fractional re-curreting was performed to establish the state of the disease. The leading symptom was vaginal bleeding in 65.5% of the cases in the postmenopausal period. Eighty-six percent of the patients presented with obesity (BMI > 30 kg/m(2)), 23% had had an exogeneous use of estrogens. Twenty-two cases were reclassified as simple hyperplasia and excluded from further analysis. The interobserver-correlation was 91% for complex, 92% for atypical hyperplasia, and 89% for endometrioid carcinoma, representing an overall correlation of 90%. Two percent of the cases with complex hyperplasia (8/390) progressed into carcinoma and 10.5% into atypical hyperplasia. Fifty-two percent of the atypical hyperplasias (58/112) progressed into carcinomas. In the case of progestogen treatment (n = 208; P < 0.0001) 61.5% showed remission confirmed by re-curetting, compared with 20.3% of the cases without hormonal treatment (n = 182; P < 0.0001). Endometrial hyperplasia without atypia is likely to respond to hormonal treatment. Especially in postmenopausal situation, atypical hyperplasia should be treated with total hysterectomy.

Long-term follow up is required for early diagnosis of transformation of endometrial hyperplasia into malignancy. Transvaginal colour Doppler ultrasonography is a sensitive, specific and relatively non-invasive method of follow up.

To evaluate the risk of discovering an endometrial cancer when atypical hyperplasia was diagnosed by either endometrial samples using the pipelle device or hysteroscopic resection products.

A retrospective monocentric study from january 1990 to july 2000. Twenty-three patients with atypical hyperplasia were included. Initial endometrial status was provided by endometrial biopsyduring diagnosis hysteroscopy (12 cases) or by operative hysteroscopic resection products (11 cases). For 23 patients, operative hysteroscopy and analyse of products resected were performed. For all patients, there was no hysteroscopical aspect evocative of adenocarcinoma. For 23 patients, histopathological analysis of the hysterectomy piece precised the final diagnosis.

Among the 23 hysterectomy pieces, 7 adenocarcinomas were diagnosed (30.4%). Risk for discovering adenocarcinoma when atypical hyperplasia was diagnosed by means of the pipelle biopsy device was 50% (6/12). Risk for discovering adenocarcinoma when atypical hyperplasia was diagnosed by means of operative hysteroscopy resection products was 5.9 % (1/17).

Atypical endometrial hyperplasia evidenced by pipelle biopsy device is often associated with adenocarcinoma. Diagnosis hysteroscopy however does not show evident pathological aspect of adenocarcinoma in such cases. Operative hysteroscopy allows in most cases correction of endometrial status. Risk of omitting adenocarcinoma when atypical hyperplasia is discovered on hysteroscopic resection pieces is low.

Atypical hyperplasia of the endometrium is an entity that needs to be clearly distinguished from other florid hyperplastic states on the one hand and from well-differentiated adenocarcinomas on the other. This may at times be difficult on pure morphological grounds. In this study, DNA ploidy and S-phase fraction of hyperplastic, atypical and cancerous endometrium were evaluated using flow cytometry from paraffin-embedded tissues. In total, 72 cases (24 hyperplastic, 24 atypical and 24 adenocarcinomas) were selected. All hyperplastic endometria showed a diploid stemline, while 2/24 atypical hyperplasias showed aneuploid (Near-diploid) peaks. Both of these cases were severely atypical and one of these, on hysterectomy, showed early invasive carcinoma. There was no significant difference in mean S-phase fractions of hyperplastic vs. atypical endometria. DNA aneuploidy was significantly more common with much higher S-phase fractions in poorly and moderately differentiated carcinomas than in well-differentiated ones. It was concluded that aneuploid (near-diploid) peaks, if ever present in atypical hyperplasias, may indicate an aggressive disease/neoplastic transformation.

To evaluate the risk of discovering an endometrial cancer when atypical hyperplasia was diagnosed by histologic examination of hysteroscopic resection products.

A retrospective monocentric study from January 1994 to January 2001. Seventeen patients with atypical hyperplasia were included. Initial endometrial status was provided by operative hysteroscopy resection products. For all patients, there was no hysteroscopical aspect evocative of adenocarcinoma. Histopathological analysis of the hysterectomy pieces precised the final diagnosis.

Among the 17 hysterectomy pieces, one adenocarcinoma was diagnosed. Risk for discovering adenocarcinoma when atypical hyperplasia was diagnosed by operative hysteroscopy resection products was 5.9% (1/17).

Risk of omitting adenocarcinoma when atypical hyperplasia is discovered by hysteroscopy resection pieces is low.

To evaluate the role of resectoscopic surgery in the diagnosis and treatment of women with abnormal uterine bleeding and endometrial hyperplasia without atypia.

Retrospective analysis (Canadian Task Force classification II-2).

University-affiliated teaching hospital.

Twenty-five women with simple and seven with complex hyperplasia.

Hysteroscopic endometrial ablation.

In patients with simple hyperplasia, average age, parity, body mass index, and mean arterial pressure were 53.2 years, 2.4 pregnancies, 30 kg/m2, and 99.5 mm Hg, respectively; in those with complex hyperplasia corresponding figures were 48 years, 2 pregnancies, 36 kg/m2, and 100 mm Hg. Nineteen of 32 women had postmenopausal bleeding, 9 of whom were taking combined hormone replacement therapy. Two had subsequent hysterectomies, one for pain and the other for incomplete resection due to an enlarged uterus. Resection could not be completed in one morbidly obese woman. One patient died from heart disease. During the follow-up of 1 to 8 years (mean 4 yrs) all patients remained amenorrheic with no evidence of recurrent disease or progression to cancer.

Resectoscopic surgery by experienced hysteroscopists may be effective therapy for endometrial hyperplasia without atypia, especially in women at high risk for medical therapy or hysterectomy. Patient surveillance is mandatory for early detection and management of recurrent disease and progression to cancer.

To evaluate the role of the resectoscope in the diagnosis and treatment of women with abnormal uterine bleeding (AUB) and atypical endometrial hyperplasia.

Retrospective case series (Canadian Task Force classification III-3).

University-affiliated teaching hospital.

Ten women. Intervention. Hysteroscopic evaluation after preoperative endometrial biopsy indicated simple hyperplasia without atypia, complex hyperplasia with atypia, or inadequate specimen.

Atypical hyperplasia was confirmed in eight patients after total endomyometrial resection. Hysterectomy was offered to all patients but accepted by only two: one for bilateral ovarian serous cystadenomas and the second for a granulosa cell ovarian tumor. No residual endometrium was found in hysterectomy specimens. Seven women were amenorrheic and well 1 to 9 years after resection. An additional patient with amenorrhea died from colon cancer 2 years after resection.

Resectoscopic surgery confirmed or detected atypical endometrial hyperplasia in eight women and excluded it in two patients with AUB and a previous diagnosis of simple hyperplasia, atypical hyperplasia, or inadequate specimen. Skillful resectoscopic surgery may be an alternative to hysterectomy in selected patients with atypical hyperplasia who are compliant with regular and long-term follow-up.

Unopposed estrogen replacement therapy (ERT) in non-hysterectomized women creates an unacceptably high risk of endometrial neoplasia that persists even after discontinuation of hormone replacement therapy (HRT). Normally progestin should be given in addition to ERT unless a contraindication to progestin exists: in this circumstance, endometrial surveillance is essential. Continuous combined progestin-estrogen therapy (PERT) appears to offer the greatest protection from endometrial cancer. Accumulated evidence now suggests that ERT has minimal impact on breast cancer risk, especially when compared to other known or suspected breast cancer risk factors. Women developing breast cancer while on ERT have improved survival compared to non-ERT users. Recent reports suggesting an increased breast cancer risk with PERT are based on limited data sets, and are reminiscent of early alarming reports about ERT, which have been largely refuted as larger data sets have become available. Further studies are required to clarify the true impact of PERT on breast cancer and breast cancer mortality.

While the origin of tumours, whether from one cell or many, has been a source of fascination for experimental oncologists for some time, in recent years there has been a veritable explosion of information about the clonal architecture of tumours and their antecedents, stimulated, in the main, by the ready accessibility of new molecular techniques. While most of these new results have apparently confirmed the monoclonal origin of human epithelial (and other) tumours, there are a significant number of studies in which this conclusion just cannot be made. Moreover, analysis of many articles show that the potential impact of such considerations as patch size and clonal evolution on determinations of clonality have largely been ignored, with the result that a number of these studies are confounded. However, the clonal architecture of preneoplastic lesions provide some interesting insights --many lesions which might have been hitherto regarded as hyperplasias are apparently clonal in derivation. If this is indeed true, it calls into some question our hopeful corollary that a monoclonal origin presages a neoplastic habitus. Finally, it is clear, for many reasons, that methods of analysis which involve the disaggregation of tissues, albeit microdissected, are far from ideal and we should be putting more effort into techniques where the clonal architecture of normal tissues, preneoplastic and preinvasive lesions and their derivative tumours can be directly visualized in situ.

Management of endometrial precancers is compromised by longstanding debate over the natural history of endometrial hyperplasias and inconsistencies in their diagnosis. The recent demonstration that some hyperplasias, like cancers, are phenotypically monoclonal is useful in recognizing biological precancers. A clonal analysis has been undertaken of a series of 93 endometrial tissues and their morphology has been evaluated by subjective diagnostic classification and computerized morphometric analysis. A pathologist's diagnosis of atypical endometrial hyperplasia was highly associated with monoclonal growth. Both microsatellite-stable and microsatellite-unstable precancers were classified as atypical hyperplasias, indicating overlapping morphologies for these two groups. Diagnosis of non-atypical endometrial hyperplasias was not reproducible and identified a group of lesions equally likely to be monoclonal as polyclonal. Computerized morphometry resolved these lesions into monoclonal and polyclonal subgroups with a high degree of accuracy and reproducibility. The predictive value of morphometry was dominated by that fraction of the sample which consisted of stroma (volume percentage stroma). This can be measured manually and used to predict monoclonality when below the threshold value of 55%. This study shows that morphometric analysis reproducibly and precisely identifies monoclonal endometrial precancers from histological sections. It may serve, furthermore, to classify accurately lesions judged by pathologists as indeterminate (non-atypical hyperplasias). The material from this study (available at www.endometrium.org from March 1, 2000) and precisely defined architectural diagnostic criteria provide new tools for diagnostic standardization of endometrial precancers.

This study was designed to assess intraobserver and interobserver agreement in the diagnosis of 56 endometrial specimens by five European expert gynecologic pathologists using the WHO classification and to establish which histologic features are significantly associated with each classification category. The seven categories were simple hyperplasia, complex hyperplasia, atypical hyperplasia, well-differentiated adenocarcinoma, proliferative endometria, secretory endometria, and other. Slides were reviewed twice for diagnosis, with accompanying evaluation of a checklist of histologic features. These seven categories were eventually reduced to four and three for the purposes of data analysis. The four modified diagnostic categories consisted of hyperplasia (previously simple hyperplasia and complex hyperplasia), atypical hyperplasia, well-differentiated adenocarcinoma, and cyclical endometrium (previously proliferative, secretory, and other). The three diagnostic categories consisted of hyperplasia, endometrioid neoplasia (previously atypical hyperplasia and well-differentiated adenocarcinoma), and cyclical endometrium. Intraobserver and interobserver agreement was assessed using the percentage agreement and kappa statistics. The associations among the various histologic features and diagnoses was analyzed using multiple logistic regression to identify those features that were useful for distinguishing diagnostic categories. When using seven categories, kappa values ranged from 0.53 to 0.74 (percentage agreement, 61-79%) and from 0.33 to 0.59 (percentage agreement, 43-63%) for intraobserver and interobserver agreement, respectively. When using four categories, kappa values ranged from 0.68 to 0.73 (percentage agreement, 77-80%) and from 0.39 to 0.64 (percentage agreement, 54-73%) for intraobserver and interobserver agreement, respectively. When using three categories, kappa values ranged from 0.70 to 0.83 (percentage agreement, 80-89%) and from 0.55 to 0.73 (percentage agreement, 70-82%) for intraobserver and interobserver agreement, respectively. Data were analyzed in each diagnostic category. When using four or three diagnostic categories, the mean intraobserver and interobserver agreements varied less between categories and achieved higher values, with smaller 95% confidence intervals. The mean percentage agreement was lowest for complex hyperplasia and for atypical hyperplasia. For distinguishing cyclical endometrium versus hyperplasia, the useful histologic feature was glandular crowding. For hyperplasia versus atypical hyperplasia and for hyperplasia versus endometrioid neoplasia, the useful features were nuclear enlargement, nuclear pleomorphism, vesicular chromatin, and nucleoli, but of these, only nuclear pleomorphism achieved substantial mean intraobserver and interobserver agreements. For discriminating atypical hyperplasia from well-differentiated adenocarcinoma, the only useful feature was stromal alterations, which achieved only fair mean intraobserver and interobserver agreements. In summary, in endometrial biopsy or curettage specimens, the lack of agreement in the diagnoses of complex hyperplasia and atypical hyperplasia and the lack of reproducibility in the recognition of the histologic feature of stromal alterations to differentiate atypical hyperplasia from well-differentiated adenocarcinoma suggest that the histologic classification should be simplified by including a combined category for simple and complex hyperplasia, called hyperplasia, and a combined category for atypical hyperplasia and well-differentiated adenocarcinoma, called endometrioid neoplasia. Diagnoses of hyperplasia and endometrioid neoplasia are highly reproducible between observers from different institutions. Glandular crowding is the best histologic feature to differentiate cyclical endometrium from hyperplasia, whereas nuclear pleomorphism is the reproducible cytologic feature to differentiate hyperplasia from endometrioid neoplasia.

There has been considerable debate about the origin of human tumours, whether they arise from a single cell and are clonal populations or whether there needs to be some sort of co-operativity between cells for the neoplastic process to begin. Current theories subscribe to the clonal view, where a series of mutations in one cell begins a process of selection and clonal evolution leading to the development of the malignant phenotype. This review approaches this problem by asking how mutated clones, once established, spread through tissues before becoming overtly invasive. While there is substantial evidence in favour of independent origins of each tumour from a unique mutated clone, there are instances where such clones expand and remain cohesive, often involving a large area of tissue. The main example is the movement of mutated clonal crypts through the colorectal epithelium, by the process of crypt fission. In passing, the clonal architecture of early, pre-invasive lesions is examined, often with some surprising results.

To clarify the behavior of endometrial hyperplasia in a prospective study.

Fifty-one patients with endometrial hyperplasia were followed up for 6 months. Samples of endometrial tissues were taken by uterine endometrial biopsy every 4 weeks during the first 3 months and at the end of follow-up.

In 69% (35/51) of the patients histological picture of the endometrium became normal during the observation period. The lesions persisted in 17% (6/35) of the patients with simple hyperplasia, in 25% (1/4) of those with complex hyperplasia, in 14% (1/7) of those with simple atypical hyperplasia, and in 80% (4/5) of the patients with complex atypical hyperplasia. In the remaining 3 patients with simple hyperplasia, the lesions progressed to complex atypical hyperplasia by the end of follow-up, after showing a normal endometrium.

Most cases of endometrial hyperplasia, except for complex atypical hyperplasia, disappeared spontaneously within a short period of time.

Eleven cases of an unusual endometrial glandular proliferation associated with early pregnancy are reported. All lesions were incidental discoveries in first-trimester gestational endometria (two elective abortions; five spontaneous abortions; three hydatidiform moles; one tubal ectopic pregnancy). Most patients (nine of 11; 82%) were older than 30 years of age; associated clinical features included oligoovulation (two), hypertension (one), and obesity (one). All lesions were small and localized, and displayed similar histological features of variable severity including glandular expansion with smooth external contours; epithelial stratification (4 to 15 layers); cribriforming (focal to extensive); mitotic activity; bland nuclear cytology; and prominent intraglandular calcifications (eight cases; 72%). Although the natural history of these distinctive pregnancy-associated endometrial lesions was unknown, nine lesions were initially classified as benign, and two were interpreted as atypical endometrial hyperplasia or focal adenocarcinoma. Follow-up for an average of 34 months (range, 18 to 56) in nine patients showed no residual endometrial lesion (seven endometrial curettages and two hysterectomies). Three patients followed by curettage have subsequently completed successful pregnancies. This unusual lesion may represent a localized, endometrial proliferation induced by pregnancy; although some endometrial lesions may display striking architectural complexity, follow-up to date suggests a benign behavior.

Recent reports suggest that atypical endometrial hyperplasia diagnosed by biopsy or curettage is accompanied by a higher than expected risk of coexistent invasive cancer. In order to test this hypothesis we reviewed the pathology and clinical history of all patients at our institution who underwent hysterectomy for endometrial hyperplasia with or without cytologic atypia. We found 24 patients of 45 with a preoperative diagnosis of hyperplasia with cytologic atypia, and 21 with simple or complex hyperplasia without atypia. No cancers were found at surgery in the latter group nor were any significant historical differences found between the two groups. Of the patients with atypia, 12/24 (50%) had an endometrial carcinoma and nine patients (37.5%) were stage IB or greater. This is a significantly greater risk than previously reported in the literature. Endometrial hyperplasia with cytologic atypia may carry a higher risk of coexistent invasive endometrial carcinoma than previously believed. Methods to identify those patients at highest risk should be determined.