Polypoid endometriosis is a rare manifestation of endometriosis, which may mimic pelvic cancer. This subtype commonly encountered in post-menopausal women may be wrongly mistaken for a neoplasm on clinical, radiological, perioperative or pathologic assessments leading to inadequate treatment.

Polypoid endometriosis (PEM) is a rare and unique type of endometriosis. To date, no article has provided a systematic report of this disease. The current article provides a complete report on rare PEM based on ultrasound, magnetic resonance imaging, intraoperative findings and postoperative pathology data.

A 38-year-old female patient was admitted to our hospital after complaining of "vague pain in the right lower quadrant with an aggravated menstrual period for 8 mo". The patient underwent laparoscopic exploratory surgery on January 7, 2022. The postoperative pathology revealed extensive PEM.

PEM is a type of endometriosis that is a benign disease but has biological properties similar to malignant tumours.

Cryopreservation of ovarian tissue with subsequent transplantation is an efficient option for restoring fertility in women at risk of premature ovarian failure. The association between infertility and endometriosis is well recognized. Although endometriosis usually ends with the onset of natural or iatrogen menopause due to declining estrogen levels, endometriosis can in rare cases occur after menopause. This study aims to investigate women with premature menopause who were diagnosed with endometriosis during laparoscopy for ovarian tissue transplantation, and to address the questions of how endometriotic lesions after cytotoxic treatment and premature menopause might be explained, whether endometriosis affects pregnancy rates, and whether there is an association between endometriosis and the original cancer.

Seventeen patients who had undergone ovarian tissue transplantation to restore their fertility and who were diagnosed with endometriosis during transplantation were included in this retrospective study. The endometriosis foci were completely removed and ovarian tissue was transplanted into the pelvic peritoneum. Preexisting conditions, use of hormonal preparations, endometriosis stage pain assessment, as well as pregnancy and live birth rate were evaluated.

The mean age of the patients was 29.5 ± 6.3 years (range 14-39) at the time of ovarian tissue harvest and 34.6 ± 4.3 years (range 28-40) at transplantation. Prior to transplantation, four patients had taken hormone replacement therapy, four women oral contraceptives and two patients' tamoxifen. Twelve women had stage I endometriosis and five stage II endometrioses according to the rASRM classification. Four patients reported dysmenorrhea. None of the women complained of general pelvic pain or dyspareunia. The pregnancy rate in the study population was 41.2%, with a live birth rate of 35.3%. The pregnancies occurred in three cases after spontaneous conception, in four women after a natural cycle IVF/ICSI.

This study highlights the under-researched association between endometriosis in women entering premature or early menopause either after gonadotoxic treatment or due to primary ovarian insufficiency. As more and more patients seek to have their cryopreserved ovarian tissue transplanted to fulfill their desire to have children, specialists will inevitably encounter women with this condition.

Polypoid endometriosis is a rare form of endometriosis characterized by polypoid masses that histologically often resemble endometrial polyps. We report a case of rapidly progressing polypoid endometriosis that was preoperatively assumed to be advanced ovarian cancer. A 46-year-old woman, para 0, underwent laparoscopic myomectomy and left adnexectomy for uterine fibroids and a left ovarian endometrial cyst after administration of gonadotropin releasing hormone (GnRH) agonist for 4 months. Eleven months postoperatively, rapid right ovarian enlargement occurred. CT and MRI (both contrast-enhanced) showed masses in the right adnexa, cecum, sigmoid colon, and omentum, and PET-CT demonstrated increased uptake, suggesting ovarian cancer and peritoneal dissemination. The patient later developed intestinal obstruction, and colonoscopy revealed multiple polypoid lesions in the sigmoid colon. The omental tumor and right adnexa were biopsied during exploratory laparotomy, and diagnosed as polypoid endometriosis with no malignancy by permanent pathology. The right adnexal tumor shrunk markedly after 4 months of GnRH antagonist treatment. Second laparotomy was then performed for right adnexal tumor resection and ileocecectomy. Pathological examination revealed polypoid endometriosis extending from the ovary to the cecal mucosa. The patient has been asymptomatic for over 1 year postoperatively. The sigmoid colon tumor shrunk but is still present.Polypoid endometriosis predominantly affects the ovaries, colon, peritoneum, and omentum of patients in their 40s and 50s. It is a benign disease but is often difficult to distinguish from malignancy preoperatively because it rapidly forms numerous solid lesions. Although polypoid endometriosis is rare, with no specific imaging findings, including it in a differential diagnosis may facilitate preoperative identification.

Polypoid endometriosis (PE) is a rare distinctive variant of endometriosis with morphological features resembling malignant tumors. Although a surgical procedure is usually performed for the treatment and diagnosis of PE, fertility preservation is usually desired in cases of reproductive age. However, there have been no reports of fertility-preserving treatments resulting in live births. In this study, we report three cases of PE that were diagnosed preoperatively or intraoperatively, leading to fertility preservation. Intraoperative pathological diagnosis, hysteroscopy, and hormone therapy before treatment were useful for preoperative diagnosis in the three cases. Two of the three patients got pregnant and the pregnancy progressed to a live birth. We also performed a literature review to identify the clinical characteristics indicative of the preoperative diagnosis of PE.

Encapsulated peritoneal sclerosis (EPS) is a rare, but frequently fatal, long-term complication of peritoneal dialysis. Endometriosis is a common gynecological problem but hemoperitoneum due to endometriosis has been reported to be extremely rare in hemodialysis (HD) patients. A 25-year-old female HD patient was admitted to our clinic with nausea, vomiting, abdominal pain, and weight loss for last 3 months. Candida tropicalis and Candida glabrata were isolated in the fungal cultures from peritoneal fluid. Her abdominal computerized tomography scan has shown irregular peritoneal calcifications, diffuse peritoneal thickening, dilatation of the small bowel loops, and cocoon formation which all were typical for EPS. Hemoperitoneum was reported to recur for four times with intervals suggesting menstrual cycles. Her peritoneal biopsy, along with the signs of EPS, has also revealed the presence of endometriosis. The patient died with symptoms of septic shock in the first year of EPS diagnosis.

This an interesting case of an asymptomatic 60-year-old postmenopausal patient with an incidental pelvic mass mimicking a pelvic malignancy on imaging. Biopsy revealed findings consistent with polypoid endometriosis. After discontinuation of hormone replacement therapy, the mass showed decrease in size on follow-up imaging. Polypoid endometriosis is a rare but distinct variant of endometriosis with histopathologic features akin to an endometrial polyp. Clinical and imaging features of polypoid endometriosis differ from classic endometriosis. While classic endometriosis predominates in premenopausal women, polypoid endometriosis more commonly affects peri- to postmenopausal women and is associated with the exposure to Tamoxifen or hormone replacement therapy. Imaging features that aid in the diagnosis of polypoid endometriosis are a T2 hyperintense polypoid mass with signal characteristics similar to endometrium, a T2 hypointense peripheral rim, contrast enhancement pattern mirroring the enhancement of the endometrium, and lack of diffusion restriction. Radiologists should be familiar with polypoid endometriosis because this clinically and morphologically distinct variant may mimic malignant neoplasms on imaging.

Thoracic endometriosis-related pneumothorax (TERP) or thoracic endometriosis syndrome (TES) usually occurs in women of childbearing age and affects the right thorax. Menopausal and left-sided cases are rare. A case of left-sided TERP in a postmenopausal woman after adjuvant endocrine therapy for breast cancer is reported. A 51-year-old woman underwent video-assisted thoracic surgery for recurrent left pneumothorax. Immunohistological examination of the resected specimen from the apical bleb and a diaphragmatic blueberry spot demonstrated thoracic endometriosis. Even in the case of a left-sided pneumothorax in a menopausal woman, clinicians should be aware of the possibility of TERP.

Tamoxifen is a medication often used for the treatment and prevention of breast cancer. It is classically associated with several gynecological side effects to include a thickened endometrial stripe, increased uterine polyp formation, and an increased risk of uterine cancer. Rarely tamoxifen use has been associated with proliferation of endometriosis often severe enough to mimic a late-stage gynecologic malignancy.

A 62-year-old Gravida 0 postmenopausal female with a medical history of severe obesity, infertility, and preventative tamoxifen use presented for evaluation of gross hematuria. A CT urogram was performed and demonstrated findings concerning for carcinomatosis, likely gynecologic in origin. Cervical cancer screening was up-to-date and she had a negative colonoscopy within the prior 2 years. Serum tumor markers were remarkable only for a mildly elevated CA125 of 37.6. Diagnostic laparoscopy demonstrated apparent operable carcinomatosis limited to the pelvis. The procedure was converted to an exploratory laparotomy, where radical tumor cytoreduction was performed to no gross residual disease. Frozen sections performed intraoperatively were unclear of origin but suggestive of low malignant potential. Final pathology resulted for endometriosis.

This case illustrates a presentation of endometriosis in a postmenopausal woman mimicking advanced mullerian malignancy. The patient's estrogenic state from obesity in combination with the agonist action of the tamoxifen likely contributed to her rare presentation. While findings such as a thickened endometrial stripe are typical of tamoxifen use, such widespread proliferation of endometriosis resulting in a pelvic mass, genito-urinary obstruction, and plaque-like pelvic spread are not.

Endometriosis is a benign estrogen dependent condition rarely problematic in a postmenopausal patient. Tamoxifen use in the setting of an obese patient may contribute to a proliferation of pre-existing endometriosis which resembles an aggressive late-stage gynecological malignancy.