Treatment for Ductal Carcinoma in Situ (DCIS) includes surgery followed by radiotherapy (RT) to reduce local recurrence (LR) risk, though RT may be overtreatment for some patients. The Oncotype DX Breast DCIS Score® test is a genomic test that provides individualised LR risk estimates. This study evaluates the impact of the Oncotype test on RT recommendations, patient anxiety and decisional conflict.

Women aged ≥45 years with DCIS up to 25mm treated with breast-conserving surgery were invited to participate. Initial RT recommendations and 10-year LR risk predictions were made before Oncotype testing. Post Oncotype testing, final RT recommendations were recorded. Patients completed decisional conflict and anxiety questionnaires before and after receiving Oncotype results.

A total of 71 participants were included with a median age of 59. Ninety percent of DCIS was intermediate/high-grade with a median size of 12mm. Oncologists changed RT recommendations in 28% (20/71) of cases after receiving the Oncotype result; 21% changed from RT to no RT and 7% from no RT to RT. In 79% of cases, the oncologists' LR estimates were higher than Oncotype predictions. Post Oncotype testing, patient decisional conflict and anxiety decreased.

The Oncotype test changed treatment recommendations regarding adjuvant RT in almost a third of patients. Additionally, the assay was associated with reduced treatment-related decisional conflict and anxiety in patients. LR risk predictions by oncologists were higher than the Oncotype predictions highlighting a need for additional tools to aid decision-making.

Breast-conserving surgery for larger ductal carcinoma in situ (DCIS) remains limited. We compare the attempted use and success rates of lumpectomy surgery in patients with DCIS measuring ≥ 4 cm versus < 4 cm.

A retrospective review was conducted using the institutional tumor registry to identify cases of pure DCIS that were surgically treated from 2015 to 2022. Clinical-pathological data were abstracted from electronic medical records. Pathologic tumor size on initial surgery was used to define the two cohorts. Comparisons of variables were made using Chi-square and ANOVA tests.

A total of 669 patients, 84% (562) with tumors measuring < 4 cm and 16% (107) ≥ 4 cm were identified. Lumpectomy was the initial surgery performed for 89% of women with lesions measuring < 4 cm on preoperative imaging studies compared to 64% of those ≥ 4 cm. Overall, 461 (92.9%) of 496 in the < 4 cm succeeded at lumpectomy compared to 36 (56.3%) of 64 in the ≥ 4 cm group. Re-excision lumpectomies or mastectomy were performed in 27% and 44% of the < 4 cm and ≥ 4 cm subgroups. Lumpectomy was achieved for 70% of women with tumors in the 4 to 5.9 cm range compared to 33% in the 6-7.9 cm and the ≥ 8 cm groups. There were no local recurrences in the ≥ 4 cm group at an average of 4.4 years follow-up.

Lumpectomy is a viable option for many patients with DCIS ≥ 4 cm, especially those measuring < 6 cm, though repeat re-excisions may be required after initial attempt.

Ductal carcinoma in-situ (DCIS) is a non-obligate precursor breast lesion with variable tendency to become invasive malignancy. Multiple studies have attempted to identify patient groups that could avoid radiation therapy (RT). We investigated the recent surgical management of DCIS in Australia and New Zealand (ANZ) and evaluated the likely rates of RT delivery dependent on differing low risk predictive criteria compared to actual practice.

The BreastSurgANZ Quality Audit identified patients with DCIS from 2018 to 2022. Data were analysed on multiple DCIS characteristics as well as postoperative RT recommendations. Existing potential RT avoidance characteristics, low risk classification criteria (LRCC) and RTOG 9804, were tested against the cohort.

7790 cases were analysed with 5323 (68.33 %) undergoing breast conservation surgery (BCS). There was higher median age, lower tumour grade and smaller size in the BCS group compared to mastectomy (p < 0.001). According to the BQA, 25.38 % of patients had RT omitted. Using LRCC, 1659 patients (31.17 %) could omit RT but only 760 (45.81 %) of those patients did. When using RTOG 9804 criterion, 1287 patients (24.18 %) could omit RT but only 447 (34.73 %) did. Of 3477 patients with neither low risk classifying characteristics, 553 (15.9 %) had no RT.

BCS is the preferred surgical management of DCIS in ANZ. Currently RT is omitted following BCS in 25 % of cases. Using LRCC and RTOG 9804 low risk classifiers there was inconsistent avoidance of RT, whereas RT was avoided in 15.9 % of higher risk patients. More consistent and transparent selection methods are desirable and currently genomic testing and clinico-molecular tools appears promising.

Ductal Carcinoma In Situ (DCIS) is not an obligate precursor to invasive breast cancer and can exhibit variations in clinical presentation, genetics, biomarkers, and morphological features. There are contrasting views in literature with regard to prognostic significance of DCIS component in invasive cancer. Hence, this study aimed to evaluate how the co-occurrence of DCIS affects the prognosis of people with invasive breast cancer (IBC). A retrospective nested cohort observational study of patients with invasive breast cancer with and without DCIS component was conducted to compare the types of metastases developed on the subsequent follow-up, treatment details, event free survival and other histopathological parameters. There was a significant difference (p = 0.014) in the mean age at diagnosis between patients of IBC with concurrent DCIS (45 ± 11.18 years) and those who had IBC alone (53.24 ± 10.45 years). Invasive cancer with concurrent DCIS component tends to be more common in patients less than 50 years age group (p = 0.03). Majority (75.56%) of the patients were in post-menopausal stage. Patients with concurrent DCIS had higher frequencies of tumors of T1/ T2 stages and zero nodal status. Higher frequencies of local recurrence and visceral metastases were observed in patients with DCIS component compared to patients with IBC alone. Majority had received complete treatment. Longer event free survival was noted in patients with DCIS component compared to those with IBC alone. Our study demonstrated significant association of concurrent DCIS component with mean age at diagnosis in patients with invasive breast cancer. Although a trend towards favorable tumor profile was observed, larger prospective studies are required to enhance the statistical power of our findings. In view of its impact on clinical outcome, it is important to risk stratify invasive breast cancer based on the features of concurrent DCIS component.

Active monitoring for low-risk ductal carcinoma in situ (DCIS) of the breast has been proposed as an alternative to guideline-concordant care, but the safety of this approach is unknown.

To compare rates of invasive cancer in patients with low-risk DCIS receiving active monitoring vs guideline-concordant care.

Prospective, randomized noninferiority trial enrolling 995 women aged 40 years or older with a new diagnosis of hormone receptor-positive grade 1 or grade 2 DCIS without invasive cancer at 100 US Alliance Cancer Cooperative Group clinical trial sites from 2017 to 2023.

Participants were randomized to receive active monitoring (follow-up every 6 months with breast imaging and physical examination; n = 484) or guideline-concordant care (surgery with or without radiation therapy; n = 473).

The primary outcome was 2-year cumulative risk of ipsilateral invasive cancer diagnosis, according to planned intention-to-treat and per-protocol analyses, with a noninferiority bound of 5%.

The median age of the 957 participants analyzed was 63.6 (95% CI, 55.5-70.5) years in the guideline-concordant care group and 63.7 (95% CI, 60.0-71.6) years in the active monitoring group. Overall, 15.7% of participants were Black and 75.0% were White. In this prespecified primary analysis, median follow-up was 36.9 months; 346 patients had surgery for DCIS, 264 in the guideline-concordant care group and 82 in the active monitoring group. Forty-six women were diagnosed with invasive cancer, 19 in the active monitoring group and 27 in the guideline-concordant care group. The 2-year Kaplan-Meier cumulative rate of ipsilateral invasive cancer was 4.2% in the active monitoring group vs 5.9% in the guideline-concordant care group, a difference of -1.7% (upper limit of the 95% CI, 0.95%), indicating that active monitoring is not inferior to guideline-concordant care. Invasive tumor characteristics did not differ significantly between groups.

Women with low-risk DCIS randomized to active monitoring did not have a higher rate of invasive cancer in the same breast at 2 years compared with those randomized to guideline-concordant care.

ClinicalTrials.gov Identifier: NCT02926911.

Despite ductal carcinoma in situ (DCIS) being a non-obligatory precursor of invasive breast carcinoma, its diagnosis generates substantial psychological distress. The limited knowledge about the natural history of DCIS contributes to the insufficient transmission of information about DCIS to patients and the general population. The uncertainty about the progression risk to invasive carcinoma hampers adequate communication by clinicians. Breast cancer-related mortality after a DCIS diagnosis is low. However, several studies have demonstrated that DCIS patients generally overestimate the risk of developing loco-regional recurrence or dying from breast cancer. Various factors contribute to this perceived risk. Despite the lack of infiltrative growth, DCIS is treated similarly to invasive breast cancer, with surgery, radiotherapy, and hormonal therapy. Additionally, the term 'carcinoma' in DCIS provokes anxiety. Incorrect risk perception by physicians may result in overtreatment. Here, we provide an overview of epidemiologic data on mortality after DCIS. We discuss the impact of the term "ductal carcinoma in situ" on patients' and physicians' perceptions of risk. The available evidence is mostly limited to patients within the Anglosphere. Recent studies, and European studies in particular, are scarce. We identify this as an area of interest for future large-scale European studies. We discuss the potential value of the "ductal intraepithelial neoplasia" (DIN) terminology, introduced in 1998. Although replacing the concept of "DCIS" with the DIN terminology is unlikely to solve the entire problem of risk overestimation, it could be the first step to optimize doctor-patient communication and alter the current risk perception.

The standard treatment for ductal carcinoma in situ became well established through the results of several valuable clinical trials, and its therapeutic benefits have now come to be taken for granted. Ductal carcinoma in situ has an extremely good prognosis with the current treatment approach, with a 10-year breast cancer-specific survival rate of 97-98%. According to one retrospective cohort study, the breast cancer-specific survival rate of patients with low-grade ductal carcinoma in situ does not differ significantly between patients undergoing and not undergoing surgery. Some patients with ductal carcinoma in situ are not at a risk of progression to invasive cancer, but the predictors of such progression have not yet been clearly identified. Therefore, the same therapeutic strategies have been used to treat ductal carcinoma in situ and under the assumption that they have risks of invasive breast cancer, and a well-balanced risk/benefit ratio in respect of treatment has not yet been achieved. Based on the results of several recent clinical trials aimed at ensuring provision of a well-balanced treatment for patients with ductal carcinoma in situ which carries a good prognosis, de-escalation of postoperative adjuvant therapy has now begun. Currently, not only is the optimization of postoperative adjuvant therapy accelerating, but also clinical trials to de-escalate basic surgical treatments are under way. There is a possibility of achieving individualized treatment for patients with ductal carcinoma in situ of the breast with reduced treatment intervention. In this review, we present an overview of the current treatment approaches and potential future management strategies for ductal carcinoma in situ of the breast.

(1) Background: To make recommendations on the most effective therapy options for Ductal Carcinoma of the Breast (DCIS) patients; (2) Methods: MEDLINE, EMBASE, Cochrane Library, PROSPERO databases, and main relevant guideline websites were searched. Draft versions of the guideline went through formal internal and external reviews, with a final approval by the Program in Evidence Based Care and the DCIS Expert Panel. The Grading of Recommendations, Assessment, Development, and Evaluation approach was followed; (3) Results: Based on the current evidence from the systematic review and this guideline authors' clinical opinions, initial draft recommendations were developed to improve the management of patients with DCIS. After a comprehensive internal and external review process, ten recommendations and 27 qualifying statements were eventually made. This guideline includes recommendations for the primary treatment of DCIS with surgical treatment and/or radiation therapy and the management of DCIS after primary treatment for patients with DCIS, including DCIS with microinvasion (<1 mm through the duct); (4) Conclusions: The current guideline was created after a systematic review and a comprehensive internal and external review process. We believe this guideline provides valuable insights that will be useful in clinical decision making for health providers.

Trials demonstrating benefits of tamoxifen for women with ductal carcinoma in situ (DCIS) were published > 20 years ago; yet subsequent uptake of endocrine therapy was low. We estimated endocrine therapy initiation in women with DCIS between 2001 and 2018 in a community setting, reflecting more recent years of diagnosis than previous studies.

This retrospective cohort included adult females ≥ 20 years diagnosed with first primary DCIS between 2001 and 2018, followed through 2019, and enrolled in one of three U.S. integrated healthcare systems. We collected data on endocrine therapy dispensings (tamoxifen, aromatase inhibitors [AIs]) from electronic pharmacy records within 12 months after DCIS diagnosis. Using generalized linear models with a log link and Poisson distribution, we estimated endocrine therapy initiation rates over time and by patient, tumor (including estrogen receptor [ER] status), and treatment characteristics.

Among 2020 women with DCIS, 587 (29%) initiated endocrine therapy within 12 months after diagnosis (36% among 1208 women with ER-positive DCIS). Among women who used endocrine therapy, 506 (86%) initiated tamoxifen and 81 (14%) initiated AIs. Age-adjusted endocrine therapy initiation declined from 34 to 21% between 2001 and 2017; between 2015 and 2018, AI use increased from 8 to 35%. Women less likely to initiate endocrine therapy were ER-negative or had borderline/unknown or no ER test results, ≥ 65 years at diagnosis, Black, and received no radiotherapy.

One-third of women diagnosed with DCIS initiated endocrine therapy, and use decreased over time. Understanding why women eligible for endocrine therapy do not initiate is important to maximizing disease-free survival following DCIS diagnosis.

Breast conserving surgery (BCS) is well established for the management of ductal carcinoma in situ (DCIS), but neither randomized trials nor guidelines address management of ipsilateral breast tumor recurrence (IBTR) after BCS for DCIS.

We identified women treated with BCS for DCIS who developed IBTR as a first event. Between those treated with mastectomy versus re-BCS, we compare the clinicopathologic characteristics, the use of adjuvant radiotherapy (RT) both upfront ("primary RT") and post IBTR ("secondary RT"), of tamoxifen, the rate of third events (local, regional, distant), and both breast cancer specific (BCSS) and overall survival (OS).

Of 3001 women treated with BCS for DCIS (1978-2010), 383 developed an IBTR as a first event (1983-2023) and were treated by mastectomy (51%) versus re-BCS (49%). Compared with re-BCS, mastectomy patients at initial treatment were higher grade (74% versus 59%, p = 0.004), with more frequent primary RT (61% versus 21%, p < 0.001). Third local events were more frequent for re-BCS than mastectomy (16% versus 3%, p = 0.001), but there were no differences in breast cancer specific or overall survival.

For isolated IBTR following BCS for DCIS and treated by mastectomy versus re-BCS (1) mastectomy was associated with less favorable initial pathology and more frequent use of primary RT, (2) re- recurrence was more frequent with re-BCS, and (3) BCSS and OS were comparable. Our data suggest a wider role for re-BCS and further study of the relationship between secondary RT and the rate of third breast events.

Whether DCIS is associated with higher breast cancer-specific and all-cause mortality is unclear with few studies in older women. Therefore, we examined DCIS and breast cancer-specific, cardiovascular (CVD)-specific, and all-cause mortality among Women's Health Initiative (WHI) Clinical Trial participants overall and by age (< 70 versus ≥ 70 years).

Of 68,132 WHI participants, included were 781 postmenopausal women with incident DCIS and 781 matched controls. Serial screening mammography was mandated with high adherence. DCIS cases were confirmed by central medical record review. Adjusted multivariable Cox proportional hazard regression models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CI). Kaplan Meier (KM) plots were used to assess 10-year and 20-year mortality rates.

After 20.3 years total, and 13.2 years median post-diagnosis follow-up, compared to controls, DCIS was associated with higher breast cancer-specific mortality (HR 3.29; CI = 1.32-8.22, P = 0.01). The absolute difference in 20-year breast cancer mortality was 1.2% without DCIS and 3.4% after DCIS, log-rank P = 0.026. Findings were similar by age (< 70 versus ≥ 70 years) with no interaction (P interaction = 0.80). Incident DCIS was not associated with CVD-specific mortality (HR 0.77; CI-0.54-1.09, P = 0.14) or with all-cause mortality (HR 0.96; CI = 0.80-1.16, P = 0.68) with similar findings by age.

In postmenopausal women, incident DCIS was associated with over three-fold higher breast cancer-specific mortality, with similar findings in younger and older postmenopausal women. These finding suggest caution in using age to adjust DCIS clinical management or research strategies.

The density of tumour-infiltrating lymphocytes (TILs) could be prognostic in ductal carcinoma in situ (DCIS). However, manual TIL quantification is time-consuming and suffers from interobserver and intraobserver variability. In this study, we developed a TIL-based computational pathology biomarker and evaluated its association with the risk of recurrence and benefit of adjuvant treatment in a clinical trial cohort.

In this retrospective cohort study, a computational pathology pipeline was developed to generate a TIL-based biomarker (CPath TIL categories). Subsequently, the signature underwent a masked independent validation on H&E-stained whole-section images of 755 patients with DCIS from the UK/ANZ DCIS randomised controlled trial. Specifically, continuous biomarker CPath TIL score was calculated as the average TIL density in the DCIS microenvironment and dichotomised into binary biomarker CPath TIL categories (CPath TIL-high vs CPath TIL-low) using the median value as a cutoff. The primary outcome was ipsilateral breast event (IBE; either recurrence of DCIS [DCIS-IBE] or invasive progression [I-IBE]). The Cox proportional hazards model was used to estimate the hazard ratio (HR).

CPath TIL-score was evaluable in 718 (95%) of 755 patients (151 IBEs). Patients with CPath TIL-high DCIS had a greater risk of IBE than those with CPath TIL-low DCIS (HR 2·10 [95% CI 1·39-3·18]; p=0·0004). The risk of I-IBE was greater in patients with CPath TIL-high DCIS than those with CPath TIL-low DCIS (3·09 [1·56-6·14]; p=0·0013), and the risk of DCIS-IBE was non-significantly higher in those with CPath TIL-high DCIS (1·61 [0·95-2·72]; p=0·077). A significant interaction (pinteraction=0·025) between CPath TIL categories and radiotherapy was observed with a greater magnitude of radiotherapy benefit in preventing IBE in CPath TIL-high DCIS (0·32 [0·19-0·54]) than CPath TIL-low DCIS (0·40 [0·20-0·81]).

High TIL density is associated with higher recurrence risk-particularly of invasive recurrence-and greater radiotherapy benefit in patients with DCIS. Our TIL-based computational pathology signature has a prognostic and predictive role in DCIS.

National Cancer Institute under award number U01CA269181, Cancer Research UK (C569/A12061; C569/A16891), and the Breast Cancer Research Foundation, New York (NY, USA).

Breast cancer, as one of the most common malignancies among women globally, presents a concerning incidence rate, underscoring the importance of addressing the treatment of its precursor lesion, ductal carcinoma in situ (DCIS). Treatment decisions for DCIS, involving the balance between breast-conserving surgery (BCS) and mastectomy, remain an area requiring further investigation. This study aimed to compare influence of different surgical types on overall survival (OS) of patients with DCIS and identify specific subgroups with improved OS to develop an effective survival nomogram for patients.

Patient data from the Surveillance, Epidemiology, and End Results (SEER) database for DCIS cohort from 2010 to 2020 were retrieved. Kaplan-Meier (K-M) survival curves were utilized to compare prognostic OS of patients with different surgical methods. Cox regression analysis was employed to determine prognostic factors and establish a nomogram to predict 3-, 5-, and 10-year survival rates. The model was confirmed by Concordance Index (C-index), calibration curves, and receiver operating characteristic (ROC) curves.

A total of 71,675 patients with DCIS were included. Patients who underwent subcutaneous mastectomy (SM) demonstrated the best OS compared to other surgical types. Additionally, adjuvant radiotherapy or chemotherapy in combination with surgery significantly improved OS compared to surgery alone. Among DCIS patients aged ≤74 years, those who underwent SM benefited the most in terms of OS, while in the age group of 63-74 years, patients who underwent BCS had significantly higher OS than those who underwent total (simple) mastectomy (TM)/modified radical mastectomy (MRM). Multiple factors were associated with improved OS in DCIS patients, and these factors were integrated into the nomogram to establish OS predictions. The C-index, calibration curves, and ROC curves indicated that the nomogram was suitable for assessing patient prognosis.

This study demonstrated that SM treatment yielded the best survival rates for DCIS patients, providing important guidance for future surgical decision-making. Moreover, identifying multiple independent factors related to survival and establishing reliable survival nomograms can assist physicians in developing personalized treatment plans and prolonging patient survival.

Ductal carcinoma in situ (DCIS) accounts for 15-25% of all breast cancer diagnoses. Its prognosis is excellent overall, the main risk being the occurrence of local breast events, as most cases of DCIS do not progress to invasive cancer. Systematic screening has greatly increased the incidence of this non-obligate precursor of invasion, lending urgency to the need to identify DCIS that is prone to invasive progression and distinguish it from non-invasion-prone DCIS, as the latter can be overdiagnosed and therefore overtreated. Treatment strategies, including surgery, radiotherapy, and optional endocrine therapy, decrease the risk of local events, but have no effect on survival outcomes. Active surveillance is being evaluated as a possible new option for low-risk DCIS. Considerable efforts to decipher the biology of DCIS have led to a better understanding of the factors that determine its variable natural history. Given this variability, shared decision making regarding optimal, personalised treatment strategies is the most appropriate course of action. Well designed, risk-based de-escalation studies remain a major need in this field.

Advances in oncology treatment methods have improved outcomes and quality of life for patients with cancer. However, care of these patients can be complex, and the contribution of physicians from different specialties is crucial. This article highlights important publications from 2023 on topics across a wide spectrum relating to the management of oncology patients. The literature was screened for significant new evidence that is relevant to internal medicine specialists and subspecialists whose focus is not oncology. Two articles address the importance of social interventions targeting end-of-life care for low-income and minority patients and the well-being of caregivers. Two additional articles address screening considerations in patients at risk for colorectal and lung cancer. Two more articles address safe use of hormone-related therapies to treat symptoms of menopause and prevent disease recurrence or progression in patients diagnosed with noninvasive breast neoplasia. Finally, several articles were included on topics related to COVID-19 vaccination in patients with cancer, use of cannabinoids for cancer pain control, chronic autoimmune adverse effects related to use of immune checkpoint inhibitors, and the incidence of second primary neoplasms.

Similar to invasive breast cancer, ductal carcinoma in situ is also going through a phase of changes not only from a technical but also a conceptual standpoint. From prescribing radiotherapy to everyone to personalized approaches, including radiotherapy omission, there is still a lack of a comprehensive framework to guide radiation oncologists in decision making. Many pieces of the puzzle are finding their place as high-quality data mature and are disseminated, but very often, the interpretation of risk factors and the perception of risk remain very highly subjective. Sharing the therapeutic choice with patients requires effective communication for an understanding of risks and benefits, facilitating an informed decision that does not increase anxiety and concerns about prognosis. The purpose of this narrative review is to summarize the current state of knowledge to highlight the tools available to radiation oncologists for managing DCIS, with an outlook on future developments.

Ductal carcinoma in situ (DCIS) represents pre-invasive breast carcinoma. In untreated cases, 25-60% DCIS progress to invasive ductal carcinoma (IDC). The challenge lies in distinguishing between non-progressive and progressive DCIS, often resulting in over- or under-treatment in many cases. With increasing screen-detected DCIS in these years, the nature of DCIS has aroused worldwide attention. A deeper understanding of the biological nature of DCIS and the molecular journey of the DCIS-IDC transition is crucial for more effective clinical management. Here, we reviewed the key signaling pathways in breast cancer that may contribute to DCIS initiation and progression. We also explored the molecular features of DCIS and IDC, shedding light on the progression of DCIS through both inherent changes within tumor cells and alterations in the tumor microenvironment. In addition, valuable research tools utilized in studying DCIS including preclinical models and newer advanced technologies such as single-cell sequencing, spatial transcriptomics and artificial intelligence, have been systematically summarized. Further, we thoroughly discussed the clinical advancements in DCIS and IDC, including prognostic biomarkers and clinical managements, with the aim of facilitating more personalized treatment strategies in the future. Research on DCIS has already yielded significant insights into breast carcinogenesis and will continue to pave the way for practical clinical applications.

Increasing rates of diagnosis of ductal carcinoma in situ (DCIS), given the widespread use of mammography, is a global trend. Various attempts have been made in the selection of surgical methods and application of radiation therapy (RT), and the prevalence of infectious diseases has also affected these attempts. This study aimed to investigate evolving treatment patterns and trends in the management of DCIS in South Korea.

We conducted a comprehensive search of the Korean Health Insurance Review and Assessment Service-National Patient Sample (HIRA-NPS) database and selected patients who underwent breast surgery following a DCIS diagnosis between 2009 and 2020. Based on this sample, the analyses were weighted according to the Korean population. We examined annual variations in mastectomy types, reconstructive procedures, and RT utilization from a multidisciplinary perspective.

In our weighted sample, 43,780 patients with DCIS underwent surgery, with a consistent annual increase of 10%. The proportion of lumpectomy procedures increased from 56.7% to 65.4%, showing a greater growth rate than that of total mastectomies (TMs). Following the availability of reconstruction data in 2015, shifts have emerged toward a preference for implant-based autologous tissue reconstruction. As we transitioned to the latter part of our study, the trend was marked by the increasing adoption of hypofractionated RT and omission of RT. Of the patients who underwent lumpectomy in 2020, 25.6% adopted hypofractionated RT and 53.8% omitted RT. This transformation was particularly evident among older patients, individuals treated in metropolitan areas, and those treated in small-sized healthcare facilities.

Our study sheds light on the changing landscape of DCIS treatment in South Korea incorporating perspectives from surgeons, plastic surgeons, and radiation oncologists. We observed an increase in the rates of lumpectomy and implant-based reconstruction. Adoption of hypofractionated RT and omission of RT showed increasing trends.

We report the 20-year rate of ipsilateral breast event (IBE) for patients with ductal carcinoma in situ (DCIS) treated with lumpectomy without radiation on a non-randomized prospective clinical trial. Patients were enrolled in cohort 1: low- or intermediate-grade DCIS, size ≤ 2.5 cm (n = 561); or cohort 2: high-grade DCIS, size ≤ 1 cm (n = 104). The Kaplan-Meier method was used to estimate time-to-event distributions. Cox proportional hazard methods were used to estimate hazard ratios (HRs) and tests for significance for event times. 561 patients were enrolled in cohort 1 and 104 in cohort 2. After central pathology review, 26% in cohort 1 were recategorized as high-grade and 26% in cohort 2 as low- or intermediate-grade. Mean DCIS size was similar at 7.5 mm in cohort 1 and 7.8 mm in cohort 2. Surgical margin was ≥3 mm in 96% of patients, and about 30% received tamoxifen. Median follow-up was 19.2 years. There were 104 IBEs, of which 54 (52%) were invasive. The IBE and invasive IBE rates increased in both cohorts up to 15 years, then plateaued. The 20-year IBE rates were 17.8% for cohort 1 and 28.7% for cohort 2 (p = 0.005), respectively. Invasive IBE occurred in 9.8% and 15.1% (p = 0.09), respectively. On multivariable analysis, IBE risk increased with size and was higher in cohort 2, but grade and margin width were not significantly associated with IBE. For patients with DCIS treated with excision without radiation, the rate of IBE increased with size and assigned cohort mostly in the first 15 years.

Few studies evaluate oncological safety in complex oncoplastic breast-conserving surgery(C-OBCS) for DCIS. It still needs to be defined whether it is equivalent to standard breast conservation(S-BCS) or an alternative to skin-sparing mastectomy(SSM). This study compares local recurrence rates(LR), disease-free survival(DFS) and overall survival (OS) between the three surgical techniques.

We conducted a retrospective register-based study on LR, DFS and OS of patients operated with S-BCS(n=1388), C-OBCS (n=106) or skin-sparing mastectomy (n=218) for DCIS diagnosed 2007-2020. Data was extracted from the Norwegian Breast Cancer Registry.

In the S-BCS, C-OBCS and SSM groups, median age was 60, 58 and 51 years (p<0.001), median size 15, 25, and 40 mm (p<0.001) and median follow-up 55, 48 and 76 months. At ten years, the overall LR was 12.7%, 14.3% for S-BCS, 11.2% for C-OBCS and 6.8% for SSM. Overall DFS at ten years was 82.3%, 80.5% for S-BCS, 82.4% for C-OBCS and 90.4% for SSM. At ten years, the OS was 93.8%, 93.0% in S-BCS, 93.3% in C-OBCS and 96.6% in the SSM group. Weighted Kaplan Meier plots showed that SSM had a significantly higher DFS than S-BCS (p=0.003) and C-OBCS (p=0.029). DFS in C-OBCS versus S-BCS and the difference in OS was not significant (p=0.264).

SSM had a significantly higher DFS than S-BCS and C-OBCS. The difference in DFS between S-BCS and C-OBCS, and OS between the three groups was not statistically significant. Our study suggests that C-OBCS is a safe alternative to S-BCS and SSM.

With progress in treatments, breast ductal carcinoma in situ (DCIS) outcomes have substantially improved. However, as various treatment methods are used in different countries and institutions, consensus on the optimal treatment method is lacking. This study aimed to analyze the prognostic factors and provide a reference for optimizing the clinical treatment of DCIS.

This retrospective clinical study collected data from DCIS patients at the Sun Yat-sen University Cancer Center from 2010 to 2017. The Kaplan-Meier method and Cox regression model were used to assess disease-free survival (DFS), overall survival (OS), and local control (LC) rates.

Among the 483 included patients, 83.6% (404) underwent mastectomies. The median follow-up time was 101 months. The number of patients undergoing breast-conserving surgery (BCS) with radiotherapy has gradually increased. Axillary lymph node dissection was the main surgery performed from 2010 to 2015, and the proportion of sentinel lymph node biopsies (SLNBs) has increased. LC and DFS rates with BCS without radiotherapy were significantly lower than those with mastectomy (P = .002; P < .001). Additionally, the patients who did not undergo axillary surgery had worse LC and OS rates than those who underwent SLNB (P = .028 and P = .038). Endocrine therapy (ET) or its duration had no significant effect on prognosis.

In conclusion, BCS without radiotherapy and lack of axillary surgery were independent prognostic factors. We recommend performing BCS with radiotherapy and SLNB more in clinical practice, as well as shortening the ET duration.

Ductal carcinoma in situ (DCIS) incidence has risen rapidly with the introduction of screening mammography, yet it is unclear who benefits from both the amount and type of adjuvant treatment (radiation therapy, (RT), endocrine therapy (ET)) versus what constitutes over-treatment. Our goal was to identify the effects of adjuvant RT, or ET+/- RT versus breast conservation surgery (BCS) alone in a large multi-center registry of retrospective DCIS cases (N = 1,916) with median follow up of 8.2 years. We show that patients with DCIS who took less than 2 years of adjuvant ET alone have a similar second event rate as BCS. However, patients who took more than 2 years of ET show a significantly reduced second event rate, similar to those who received either RT or combined ET+RT, which was independent of age, tumor size, grade, or period of diagnosis. This highlights the importance of ET duration for risk reduction.

This study aims to evaluate the reproducibility of findings from randomized controlled trials regarding adjuvant hormone therapy (HT) for breast ductal carcinoma in situ (DCIS) in a real-life scenario.

This retrospective cohort study used Fundação Oncocentro de São Paulo database. It included DCIS patients DCIS who received breast-conserving surgery and postoperative radiation therapy. The endpoints were local control (LC), breast cancer-specific survival (BCSS), and overall survival (OS).

We analyzed 2192 patients treated between 2000 and 2020. The median FU was 48.99 months. Most patients (53.33%; n = 1169) received adjuvant HT. Patients not receiving adjuvant HT tend to be older (P = .021) and have a lower educational level (P < .001). At the end of FU, 1.5% of patients had local recurrence, and there was no significant difference between groups (P = .19). The 10-year OS and BCSS were 89.4% and 97.5% for adjuvant HT versus 91.5% and 98.5% for no adjuvant HT, respectively, and there were no significant differences between groups. The 10-year OS was 93.25% for medium/high education level versus 87.31% for low (HR for death 0.51; 95% CI, 0.32-0.83; P = .007).

The benefits of adjuvant HT for DCIS were not reproduced in a Brazilian cohort. Education significantly impacted survival and HT usage, reflecting the influence of socioeconomic factors. These findings can allow for more precise interventions.

Background To analyze the feasibility of omitting postoperative radiotherapy (PORT) after breast-conserving surgery (BCS) in Japanese patients with ductal carcinoma in situ (DCIS). Materials and methods We retrospectively analyzed 88 patients with small pure DCIS (median diameter 1.1 cm, ≤ 4 cm) who underwent BCS with (n = 39) or without (n = 49) PORT. The primary and secondary endpoints were ipsilateral breast tumor recurrence (IBTR) and overall survival (OS), respectively, between the groups that received PORT and those that did not. Results The PORT group included a high number of margin-positive cases. The incidence of IBTR was 2.4% (95% confidence interval (CI), 0.3-15.7%) and 2.8% (95% CI, 0.4-18.2%) at five years and 5.5% (95% CI, 1.4-20.6%) and 2.8% (95% CI, 0.4-18.2%) at 10 years in patients without and with PORT, respectively (p = 0.686). In the margin-negative group, only one patient showed IBTR without RT (2.3%), whereas no patient with PORT experienced IBTR (0%). To date, there have been no regional or distant metastases; therefore, no patient has experienced breast cancer-related deaths. The OS rates were 97.7% (95% CI, 84.9-99.6%) and 100% at 10 years in patients without and with PORT, respectively (p = 0.372). Conclusion This study suggests that the omission of PORT after BCS could be a feasible option for selected Japanese patients but requires further investigation to identify the low-risk factor in patients who can omit PORT.

With more than 60,000 new cases of breast cancer in mainland France in 2023 and 8% of all cancer deaths, breast cancer is the leading cancer in women in terms of incidence and mortality. While the number of new cases has almost doubled in 30 years, the percentage of patients at all stages alive at 5 years (87%) and 10 years (76%) testifies to the major progress made in terms of screening, characterisation and treatment. However, this progress, rapid as it is, needs to be evaluated and integrated into an overall strategy, taking into account the characteristics of the disease (stage and biology), as well as those of the patients being treated. These are the objectives of the St Paul-de-Vence recommendations for clinical practice. We report here the summary of the votes, discussions and conclusions of the Saint-Paul-de-Vence 2022-2023 RPCs.

To examine the association between size and margin status of ductal carcinoma in situ (DCIS) and risk of developing ipsilateral invasive breast cancer and ipsilateral DCIS after treatment, and stage and subtype of ipsilateral invasive breast cancer.

Multinational, pooled cohort study.

Four large international cohorts.

Patient level data on 47 695 women with a diagnosis of pure, primary DCIS between 1999 and 2017 in the Netherlands, UK, and US who underwent surgery, either breast conserving or mastectomy, often followed by radiotherapy or endocrine treatment, or both.

The main outcomes were 10 year cumulative incidence of ipsilateral invasive breast cancer and ipsilateral DCIS estimated in relation to DCIS size and margin status, and adjusted hazard ratios and 95% confidence intervals, estimated using multivariable Cox proportional hazards analyses with multiple imputed data RESULTS: The 10 year cumulative incidence of ipsilateral invasive breast cancer was 3.2%. In women who underwent breast conserving surgery with or without radiotherapy, only adjusted risks for ipsilateral DCIS were significantly increased for larger DCIS (20-49 mm) compared with DCIS <20 mm (hazard ratio 1.38, 95% confidence interval 1.11 to 1.72). Risks for both ipsilateral invasive breast cancer and ipsilateral DCIS were significantly higher with involved compared with clear margins (invasive breast cancer 1.40, 1.07 to 1.83; DCIS 1.39, 1.04 to 1.87). Use of adjuvant endocrine treatment was not significantly associated with a lower risk of ipsilateral invasive breast cancer compared to treatment with breast conserving surgery only (0.86, 0.62 to 1.21). In women who received breast conserving treatment with or without radiotherapy, higher DCIS grade was not significantly associated with ipsilateral invasive breast cancer, only with a higher risk of ipsilateral DCIS (grade 1: 1.42, 1.08 to 1.87; grade 3: 2.17, 1.66 to 2.83). Higher age at diagnosis was associated with lower risk (per year) of ipsilateral DCIS (0.98, 0.97 to 0.99) but not ipsilateral invasive breast cancer (1.00, 0.99 to 1.00). Women with large DCIS (≥50 mm) more often developed stage III and IV ipsilateral invasive breast cancer compared to women with DCIS <20 mm. No such association was found between involved margins and higher stage of ipsilateral invasive breast cancer. Associations between larger DCIS and hormone receptor negative and human epidermal growth factor receptor 2 positive ipsilateral invasive breast cancer and involved margins and hormone receptor negative ipsilateral invasive breast cancer were found.

The association of DCIS size and margin status with ipsilateral invasive breast cancer and ipsilateral DCIS was small. When these two factors were added to other known risk factors in multivariable models, clinicopathological risk factors alone were found to be limited in discriminating between low and high risk DCIS.

DCIS detection has increased dramatically since the introduction of screening mammography. Current guidance concordant care recommends surgical intervention for all patients with DCIS, followed by radiation and/or endocrine therapy for some. Adjuvant therapies after surgical excision have reduced recurrence rates but not breast cancer mortality. Given the lack of evidence of current treatment regimens and the morbidity associated with these treatments, there is concern that DCIS is over-treated. Active surveillance may be a favorable alternative for selected patients and is currently being investigated through four international clinical trials.

Practice indicators (PI) measure provided care making use of real-world data. This study describes trends and variations in adjuvant treatment of early breast cancer (EBC) using the European Society of Breast Cancer Specialists (EUSOMA) database.

The analysis was conducted on anonymous cumulative data registered by 56 certified breast centres, which all entered at least 500 new diagnoses in the database in the 10-year period 2010-2019. Practice trends of radiotherapy, endocrine treatment, chemotherapy, and anti-HER2 therapy were evaluated. The association with age group (<50, 50-69, ≥70) and geographical area of the centre (Northern, Central, Southern Europe; NE, CE, SE) was assessed with the Pearson Chi2 test for independence in contingency tables.

In total, 150,150 patients with EBC were selected. Overall, radiotherapy was administered more frequently in NE centres, and conversely, endocrine, chemo-, and anti-HER2 therapy were used more frequently in SE centres (p<0.001). 46.9% of the pN1 patients received postmastectomy radiotherapy, with significant differences by age and geographical region (p < 0.001). Adjuvant endocrine treatment for endocrine-sensitive carcinoma in situ was administered in 46.1%, with a decreasing trend during the study period (58.5-34.5%; p < 0.001). Anti-HER2 therapy was delivered in 75.6% of all patients with HER2BC T1a/bN0, patients older than 70 received anti-HER2 in 67.6% in SE compared to 31.3% in NE centres.

Important variations in EBC management between European certified breast centres have been demonstrated. PI using real-world data can help to monitor, evaluate, and eventually guide and align good clinical practice in the management of breast cancer.

Radiotherapy (RT) following breast-conserving surgery (BCS) is mainly used to decrease the rate of ipsilateral breast tumor recurrence (IBTR) in women with breast ductal carcinoma in situ (DCIS). Recent studies have demonstrated that low-dose tamoxifen significantly reduces IBTR in breast DCIS. Here, we aim to determine whether the administration of low-dose tamoxifen is non-inferior to RT in preventing IBTR in patients with low-risk characteristics of breast DCIS.

This is a prospective, international, open-label, randomized, non-inferiority trial. Patients with low-risk clinicopathologic features (> 40 years old, low risk of breast cancer susceptibility gene (BRCA) 1 and BRCA2 mutations, mammographically detected unicentric and non-mass lesions, low- or intermediate-grade without comedo or necrosis, measuring < 2.5 cm with margins ≥ 3 mm, and estrogen receptor-positive status) of DCIS who underwent BCS will be randomized at a 1:1 ratio to either receive tamoxifen (5 mg/day) for 5 years or undergo RT with conventional fractions (50 Gy in 25 fractions) or hypofractionations (40.05 Gy in 15 fractions). Randomization will be stratified by the Taiwan Breast Cancer Consortium. As approximately 5% of patients cannot tolerate the side effects of low-dose tamoxifen and will receive RT, we estimate that 405 patients will be randomized to a low-dose tamoxifen arm and 405 patients to the RT arm, according to a non-inferiority margin within 5% of IBTR difference and 90% β-power noticing non-inferiority. The primary endpoints are breast tumor recurrence, including ipsilateral, regional, contralateral, and distant recurrence of breast DCIS or invasive cancer. The secondary endpoints are overall survival and adverse effects of RT and tamoxifen. Translational studies will also be conducted for this trial.

This is the first non-inferiority trial on breast DCIS. This study will provide an important recommendation for clinical physicians on whether to use low-dose adjuvant tamoxifen for patients with low-risk breast DCIS who do not want to receive adjuvant RT.

ClinicalTrials.gov, ID: NCT04046159, Registered on April 30, 2019.

Radiation therapy (RT) after breast-conserving surgery (BCS) for ductal carcinoma in situ (DCIS) reduces invasive and in situ recurrences. Whereas landmark studies suggest that a tumor bed boost improves local control for invasive breast cancer, the benefit in DCIS remains less certain. We evaluated outcomes of patients with DCIS treated with or without a boost.

The study cohort comprised patients with DCIS who underwent BCS at our institution from 2004 to 2018. Clinicopathologic features, treatment parameters, and outcomes were ascertained from medical records. Patient and tumor characteristics were evaluated relative to outcomes using univariable and multivariable Cox models. Recurrence-free survival (RFS) estimates were generated using the Kaplan-Meier method.

We identified 1675 patients who underwent BCS for DCIS (median age, 56 years; interquartile range, 49-64 years). Boost RT was used in 1146 cases (68%) and hormone therapy in 536 (32%). At a median follow-up of 4.2 years (interquartile range, 1.4-7.0 years), we observed 61 locoregional recurrence events (56 local, 5 regional) and 21 deaths. Univariable logistic regression demonstrated that boost RT was more common among younger patients (P < .001) with positive or close margins (P < .001) and with larger tumors (P < .001) of higher grade (P = .025). The 10-year RFS rate was 88.8% among those receiving a boost and 84.3% among those without a boost (P = .3), and neither univariable nor multivariable analyses revealed an association between boost RT and locoregional recurrence.

Among patients with DCIS who underwent BCS, use of a tumor bed boost was not associated with locoregional recurrence or RFS. Despite a preponderance of adverse features among the boost cohort, outcomes were similar to those of patients not receiving a boost, suggesting that a boost may mitigate risk of recurrence among patients with high-risk features. Ongoing studies will elucidate the extent to which a tumor bed boost influences disease control rates.

The risk of late distant recurrence (LDR) of estrogen receptor (ER)-positive breast cancer continues even after 5 years of endocrine treatment. Clinical Treatment Score after 5 years (CTS5) was developed and validated as a tool to assess the risk of LDR using data from Tamoxifen, Arimidex Alone or in Combinations (ATAC) and Breast International Group 1-98 (BIG1-98) trials. This study aimed to externally validate CTS5 in a real-world cohort of patients treated at an academic center in Thailand.

The study was a retrospective analytical research study of early-stage, ER-positive breast cancer patients. The primary endpoint was LDR. The risk of LDR was determined using the CTS5 calculator. Cox regression model and Kaplan-Meier survival analysis were applied for prognostic validation of CTS5. Calibration was performed by comparing observed LDR to expected LDR using the Hosmer-Lemeshow (H-L) test.

A total of 323 women were included with a median follow-up period of 11.6 years. The rate of LDR was 10.8%. The CTS5 was prognostic for LDR. C-index of the area under the ROC curve was 0.672. There was no significant difference between actual and expected numbers of LDR with an observed (O) LDR events to expected (E) number of LDR events ratio of 0.99 (0.86-1.12) (H-L P = .79) indicating a proper calibration in this cohort.

Our study validated that CTS5 is accurate in predicting the risk of LDR in ER-positive breast cancer cases in Thai patients. Its performance seemed to be better in postmenopausal patients. CTS5 could be applied in routine clinical practice to improve decisions regarding prolonged endocrine therapy, particularly in resource-limited countries where molecular profiling are inaccessible.

Advancements in research have led to the steady decline of breast cancer mortality over the past thirty years. However, breast cancer incidence has continued to rise, resulting in an undue burden on healthcare costs and highlighting a great need for more effective breast cancer prevention strategies, including targeted chemo preventative agents. Efforts to understand the etiology of breast cancer have uncovered important roles for nuclear receptors in the development and progression of breast cancer. Targeted therapies to inhibit estrogen receptor (ER) and progesterone receptor (PR) signaling (selective ER modulators, aromatase inhibitors and selective PR modulators) have shown great promise for the treatment and prevention of hormone receptor (HR)-positive breast cancer. However, these drugs do not prevent HR-negative disease. Therefore, recent efforts have focused on novel targeted therapies with the potential to prevent both HR-positive and HR-negative breast cancer. Among these include drugs that target other nuclear receptors, such as retinoic acid receptor (RAR), retinoid X receptor (RXR) and vitamin D receptor (VDR). In this review we provide an overview of recent preclinical and clinical trials targeting members of the nuclear receptor superfamily for the prevention of breast cancer.

Ductal carcinoma in situ (DCIS), especially in the era of mammographic screening, is a commonly diagnosed breast tumor. Despite the low breast cancer mortality risk, management with breast conserving surgery (BCS) and radiotherapy (RT) is the prevailing treatment approach in order to reduce the risk of local recurrence (LR), including invasive LR, which carries a subsequent risk of breast cancer mortality. However, reliable and accurate individual risk prediction remains elusive and RT continues to be standardly recommended for most women with DCIS. Three molecular biomarkers have been studied to better estimate LR risk after BCS-Oncotype DX DCIS score, DCISionRT Decision Score and its associated Residual Risk subtypes, and Oncotype 21-gene Recurrence Score. All these molecular biomarkers represent important efforts towards improving predicted risk of LR after BCS. To prove clinical utility, these biomarkers require careful predictive modeling with calibration and external validation, and evidence of benefit to patients; on this front, further research is needed. Most trials do not incorporate molecular biomarkers in evaluating de-escalation of therapy for DCIS; however, one-the Prospective Evaluation of Breast-Conserving Surgery Alone in Low-Risk DCIS (ELISA) trial-incorporates the Oncotype DX DCIS score in defining a low-risk population and is an important next step in this line of research.

Adjuvant radiotherapy and hormonotherapy after breast-conserving surgery (BCS) in ductal carcinoma in situ (DCIS) have been shown to reduce the risk of local recurrence. To predict the risk of ipsilateral breast tumor relapse (IBTR) after BCS, the Memorial Sloan Kettering Cancer Center (MSKCC) developed a nomogram to analyze local recurrence (LR) risk in our cohort and to assess its external validation.

A historical cohort study using data from 296 patients treated for DCIS at the Hospital Clínic of Barcelona was carried out. Patients who had had a mastectomy were excluded from the analysis.

The mean age was 58 years (42-75), and the median follow-up time was 10.64 years. The overall local relapse rate was 13.04% (27 patients) during the study period. Actuarial 5- and 10-year IBTR rates were 5.8 and 12.9%, respectively. The external validation of the MSKCC nomogram was performed using a multivariate logistic regression analysis on a total of 207 patients, which did not reach statistical significance in the studied population for predicting LR (p = 0.10). The expression of estrogen receptors was significantly associated with a decreased risk of LR (OR: 0.25; p = 0.004).

In our series, the LR rate was 13.4%, which was in accordance with the published series. The MSKCC nomogram did not accurately predict the IBTR in this Spanish cohort of patients treated for DCIS (p = 0.10).