Effect of tamoxifen and radiotherapy in women with locally excised ductal carcinoma in situ: long-term results from the UK/ANZ DCIS trial

Identifying Good Candidates for Active Surveillance of Ductal Carcinoma In Situ: Insights from a Large Neoadjuvant Endocrine Therapy Cohort

Ductal carcinoma in situ (DCIS) is a biologically heterogenous entity with uncertain risk for invasive ductal carcinoma (IDC) development. Standard treatment is surgical resection often followed by radiation. New approaches are needed to reduce overtreatment. This was an observational study that enrolled patients with DCIS who chose not to pursue surgical resection from 2002 to 2019 at a single academic medical center. All patients underwent breast MRI exams at 3- to 6-month intervals. Patients with hormone receptor-positive disease received endocrine therapy. Surgical resection was strongly recommended if clinical or radiographic evidence of disease progression developed. A recursive partitioning (R-PART) algorithm incorporating breast MRI features and endocrine responsiveness was used retrospectively to stratify risk of IDC. A total of 71 patients were enrolled, 2 with bilateral DCIS (73 lesions). A total of 34 (46.6%) were premenopausal, 68 (93.2%) were hormone-receptor positive, and 60 (82.1%) were intermediate- or high-grade lesions. Mean follow-up time was 8.5 years. Over half (52.1%) remained on active surveillance without evidence of IDC with mean duration of 7.4 years. Twenty patients developed IDC, of which 6 were HER2 positive. DCIS and subsequent IDC had highly concordant tumor biology. Risk of IDC was characterized by MRI features after 6 months of endocrine therapy exposure; low-, intermediate-, and high-risk groups were identified with respective IDC rates of 8.7%, 20.0%, and 68.2%. Thus, active surveillance consisting of neoadjuvant endocrine therapy and serial breast MRI may be an effective tool to risk-stratify patients with DCIS and optimally select medical or surgical management.

Significance

A retrospective analysis of 71 patients with DCIS who did not undergo upfront surgery demonstrated that breast MRI features after short-term exposure to endocrine therapy identify those at high (68.2%), intermediate (20.0%), and low risk (8.7%) of IDC. With 7.4 years mean follow-up, 52.1% of patients remain on active surveillance. A period of active surveillance offers the opportunity to risk-stratify DCIS lesions and guide decisions for operative management.

De-Escalating the Management of In Situ and Invasive Breast Cancer

Simple Summary

De-escalation of breast cancer treatment reduces morbidity and toxicity for patients. De-escalation is safe if cancer outcomes, such as recurrence and survival, remain unaffected compared to more radical regimens. This review provides an overview on treatment de-escalation for ductal carcinoma in situ (DCIS), local treatment of breast cancer, and surgery after neoadjuvant systemic therapy. Improvements in understanding the natural history and biology of breast cancer, imaging modalities, and adjuvant treatments have facilitated de-escalation of treatment over time.

Abstract

It is necessary to identify appropriate areas of de-escalation in breast cancer treatment to minimize morbidity and maximize patients’ quality of life. Less radical treatment modalities, or even no treatment, have been reconsidered if they offer the same oncologic outcomes as standard therapies. Identifying which patients benefit from de-escalation requires particular care, as standard therapies will continue to offer adequate cancer outcomes. We provide an overview of the literature on the de-escalation of treatment of ductal carcinoma in situ (DCIS), local treatment of breast cancer, and surgery after neoadjuvant systemic therapy. De-escalation of breast cancer treatment is a key area of investigation that will continue to remain a priority. Improvements in understanding the natural history and biology of breast cancer, imaging modalities, and adjuvant treatments will expand this even further. Future efforts will continue to challenge us to consider the true role of various treatment modalities.

Factors influencing the initiation of adjuvant endocrine therapy in patients with estrogen receptor-positive ductal carcinoma in situ: a single institution experience

Purpose

This study evaluates whether race, socioeconomic status, insurance type, oncological provider type, and prior cancer treatment are associated with the suggestion and acceptance of hormonal therapy in patients with estrogen receptor (ER)-positive Ductal carcinoma in situ (DCIS). This study also assesses whether disparities exist pertaining to prescription of such medications.

Methods

This single-center retrospective study included 111 patients diagnosed with DCIS between 2020 and 2021. Data collected included race, type of insurance, prescribing providers, and socioeconomic status. We used zip codes to identify the poverty levels in these areas as published in the United States Census Bureau and stratified the patients into quartiles accordingly. Chi-Square statistics were used to calculate significance levels.

Results

There was no significant correlation between the intake of hormonal therapy and race (p = 0.60), insurance (p = 0.50), socioeconomic (p = 0.58), or providers (p = 0.99). 79.3% of women were offered endocrine therapy. Of those who were offered endocrine therapy, 70.8% accepted. Of patients not on hormonal therapy, 45.8% were not recommended the medications by their provider, and 54.2% declined treatment when offered.

Conclusion

In this study, patients’ demographics and providers were not associated with adjuvant hormonal therapy initiation in DCIS. Our results show that abstaining from endocrine therapy in DCIS patients is both due to lack of provider recommendation and patient rejection of these medications. The wide variation in hormonal therapy treatment among ER-positive DCIS patients suggests a need for improved provider-patient communication regarding the risks and benefits of endocrine therapy in order to ensure a shared decision-making process.

A Novel Nomogram for Predicting Prognosis and Tailoring Local Therapy Decision for Ductal Carcinoma In Situ after Breast Conserving Surgery

Purpose: We sought to explore the role of nomogram-combined biomarkers, mammographic microcalcification and inflammatory hematologic markers in guiding local therapy decisions in ductal carcinoma in situ (DCIS) subgroups with different ipsilateral breast tumour recurrence (IBTR) risk. Methods: Between January 2009 and December 2018, consecutive patients with DCIS and breast conserving surgery (BCS) were enrolled and randomly assigned to a training cohort (n = 181) and internally validation cohort (n = 78). Multivariate analyses were performed to identify predictors of IBTR. Model performance was evaluated by the concordance index (C-index) and calibration plot. The time-to-event curves were calculated by the Kaplan−Meier methods and compared by the log-rank test. Results: In total, 259 patients were enrolled and 182 of them received whole breast irradiation (WBI). After a median follow-up of 51.02 months, 23 IBTR events occurred in the whole cohort. By multivariate analyses of training cohort, presence of microinvasion, Ki67 index >14%, mammographic-clustered fine linear microcalcifications and neutrophil/lymphocyte ratio before BCS (preop-NLR), >1.1 remained independent risk factors of IBTR to develop a nomogram. The C-indexes of the nomogram were 0.87 and 0.86 in the training and internal validation set, respectively. Calibration plots illustrated good agreement between the predictions and actual observations for 5-year IBTR. Cut-off values of nomogram point were identified as 53 and 115 points, which divided all patients into low-, intermediate- and high-risk groups. Significant differences in IBTR existed between low-, intermediate- and high-risk subgroups (p < 0.01). For the whole cohort and ER-positive tumours, the benefit of WBI was found only in the intermediate-risk subgroup, but not in those with low or high risk. Fourteen out of 23 IBTRs occurred outside the original quadrant and all occurred in the high-risk group. Conclusions: The novel nomogram demonstrated potential to separate the risk of IBTR and locations of IBTR. For the whole cohort and ER-positive tumours, the benefit of WBI was restricted to an intermediate-risk subgroup.

Tumor Infiltrating Lymphocytes in Multi-National Cohorts of Ductal Carcinoma In Situ (DCIS) of Breast

Tumor-infiltrating lymphocytes (TILs) are prognostic in invasive breast cancer. However, their prognostic significance in ductal carcinoma in situ (DCIS) has been controversial. To investigate the prognostic role of TILs in DCIS outcome, we used different scoring methods for TILs in multi-national cohorts from Asian and European women. Self-described race was genetically confirmed using QC Infinium array combined with radmixture software. Stromal TILs, touching TILs, circumferential TILs, and hotspots were quantified on H&E-stained slides and correlated with the development of second breast cancer events (BCE) and other clinico-pathological variables. In univariate survival analysis, age older than 50 years, hormone receptor positivity and the presence of circumferential TILs were weakly associated with the absence of BCE at the 5-year follow-up in all cohorts (p < 0.03; p < 0.02; and p < 0.02, respectively, adjusted p = 0.11). In the multivariable analysis, circumferential TILs were an independent predictor of a better outcome (Wald test p = 0.01), whereas younger age was associated with BCE. Asian patients were younger with larger, higher grade, HR negative DCIS lesions, and higher TIL variables. The spatial arrangement of TILs may serve as a better prognostic indicator in DCIS cases than stromal TILs alone and may be added in guidelines for TILs evaluation in DCIS.

Patterns of Care and Utilization of Radiation for Women With Good-Risk Ductal Carcinoma In Situ: A National Cancer Database Analysis

Purpose/objective(s) Lumpectomy followed by whole-breast radiation therapy (WBRT) provides a 50% recurrence rate reduction in ductal carcinoma in situ (DCIS) patients when compared to lumpectomy alone. Certain factors increase the risk of recurrence, including higher nuclear grade, large size, age less than 50, and close margins. RTOG 9804 demonstrated a reduction in local failure after WBRT with the use of adjuvant radiation in women with "good-risk disease" (mammographically detected, measuring less than or equal to 2.5 cm, with a predominant nuclear grade of 1 or 2, and a margin of greater than or equal to 1 cm, or a negative re-excision). The purpose of this study is to retrospectively identify the patterns of care in women with low-risk DCIS utilizing the National Cancer Database (NCDB). We hypothesize that with the utilization of hypofractionation, there may be an increase in the delivery of RT for these "good-risk" patients. Materials/methods The National Cancer Database was queried to identify women treated with lumpectomy for <2.5 cm, nuclear grade 1 or 2 DCIS of the breast from 2004 to 2016. Data were collected regarding age, tumor size, endocrine therapy use, ER receptor status, race, insurance type, and distance from the treatment center. The distance was stratified into quartiles consisting of 0-3.9, 4-8, 8.1-15.8, and > 15.8 miles, respectively. Radiation fractionation was collected and categorized as hypofractionation, standard fractionation, or other if fractionation could not be ascertained. Clinical and patient-related factors were compared between patients who received radiation and those who received no radiation. The frequency distributions between categorical variables were compared using the Chi-square test. Multivariable logistic regression was used to identify covariables that impacted the receipt of radiation. Results The eligibility criteria were met by a total of 12,846 patients. Of those, 6,600 (51.4%) received adjuvant WBRT. On multivariable regression, patients whose tumors were ER (OR 1.24, P<0.001) and those who had not received endocrine therapy (OR 2.24, P<0.001) were more likely to receive WBRT. Factors less likely to receive WBRT included increasing age over 50 (age 50-65 OR 0.83, P<0.001; age>65 OR 0.58, P<0.001), and distance of >15.8 miles (OR 0.78, P<0.001). The fractionation technique was categorized as standard or hypofractionated in 52.2% of patients. Of those, the use of hypofractionation increased from 0.4% in 2004 to 8.9% in 2010 and to 53.8% in 2016. Conclusion This NCDB analysis demonstrated that patients who meet the RTOG 9804 criteria for "good-risk" DCIS are less likely to receive RT as time progresses despite an increase in the utilization of hypofractionation techniques. Overall, slightly more than half of these patients receive adjuvant RT.

Randomized trial of surveillance with abbreviated MRI in women with a personal history of breast cancer- impact on patient anxiety and cancer detection

BACKGROUND

Abbreviated breast MRI (A-MRI) substantially reduces the image acquisition and reading times and has been reported to have similar diagnostic accuracy as a full diagnostic protocol but has not been evaluated prospectively with respect to impact on psychological distress in women with a prior history of breast cancer (PHBC). This study aimed to determine if surveillance mammography (MG) plus A-MRI reduced psychological distress and if A-MRI improved cancer detection rates (CDR) as compared to MG alone.

METHODS

This prospective controlled trial of parallel design was performed at a tertiary cancer center on asymptomatic women with PHBC who were randomized into two groups: routine surveillance with MG or intervention of MG plus A-MRI in a 1:1 ratio. Primary outcome was anxiety measured by four validated questionnaires at three different time-points during the study. Other parameters including CDR and positive predictive value for biopsy (PPV3) were compared between imaging modalities of MG and A-MRI. Tissue diagnoses or 1 year of follow-up were used to establish the reference standard. Linear mixed models were used to analyze anxiety measures and Fisher's exact test to compare imaging outcomes.

RESULTS

One hundred ninety-eight patients were allocated to either MG alone (94) or MG plus A-MRI (104). No significant group difference emerged for improvement in trait anxiety, worry and perceived health status (all Time-by-surveillance group interaction ps > .05). There was some advantage of A-MRI in reducing state anxiety at Time 2 (p < .05). Anxiety scores in all questionnaires were similarly elevated in both groups (50.99 ± 4.6 with MG alone vs 51.73 ± 2.56 with MG plus A-MRI, p > 0.05) and did not change over time. A-MRI detected 5 invasive cancers and 1 ductal carcinoma in situ (DCIS), and MG detected 1 DCIS. A-MRI had higher incremental CDR (48/1000(5/104) vs MG 5/1000(1/198, p = 0.01)) and higher biopsy rates (19.2% (20/104) vs MG 2.1% (2/94), p < 0.00001) with no difference in PPV3 (A-MRI 28.6% (6/21) vs MG 16.7% (1/6, p > .05).

CONCLUSION

There was no significant impact of A-MRI to patient anxiety or perceived health status. Compared to MG alone, A-MRI had significantly higher incremental cancer detection in PHBC. Despite a higher rate of biopsies, A-MRI had no demonstrable impact on anxiety, worry, and perceived health status.

TRIAL REGISTRATION

ClinicalTrials.gov ( NCT02244593 ). Prospectively registered on Sept. 14, 2014.

Radiotherapy of Breast Cancer-Professional Guideline 1st Central-Eastern European Professional Consensus Statement on Breast Cancer

The international radiotherapy (RT) expert panel has revised and updated the RT guidelines that were accepted in 2020 at the 4th Hungarian Breast Cancer Consensus Conference, based on new scientific evidence. Radiotherapy after breast-conserving surgery (BCS) is indicated in ductal carcinoma in situ (stage 0), as RT decreases the risk of local recurrence (LR) by 50-60%. In early stage (stage I-II) invasive breast cancer RT remains a standard treatment following BCS. However, in elderly (≥70 years) patients with stage I, hormone receptor-positive tumour, hormonal therapy without RT can be considered. Hypofractionated whole breast irradiation (WBI) and for selected cases accelerated partial breast irradiation are validated treatment alternatives to conventional WBI administered for 5 weeks. Following mastectomy, RT significantly decreases the risk of LR and improves overall survival of patients who have 1 to 3 or ≥4 positive axillary lymph nodes. In selected cases of patients with 1 to 2 positive sentinel lymph nodes axillary dissection can be substituted with axillary RT. After neoadjuvant systemic treatment (NST) followed by BCS, WBI is mandatory, while after NST followed by mastectomy, locoregional RT should be given in cases of initial stage III-IV and ypN1 axillary status.

Hypofractionation and Concomitant Boost in Ductal Carcinoma In Situ (DCIS): Analysis of a Prospective Case Series with Long-Term Follow-Up

We previously reported on a cohort of breast cancer patients affected with ductal carcinoma in situ (DCIS) that were treated with breast conservative surgery and hypofractionated whole-breast radiotherapy with a concomitant boost to the lumpectomy cavity. We now report on the long-term results of the oncological and toxicity outcomes, at a median follow-up of 11.2 years. We also include an analysis of the predictive factors for local recurrence (LR). Eighty-two patients with long-term observation were considered for this report. All received hypofractionated post-operative radiotherapy with a concomitant boost (45 Gy/20 fractions to the whole breast and 50 Gy/20 fractions to the lumpectomy cavity). We report on LC rates at 5 and 10 years, overall survival (OS), and breast-cancer-specific survival (BCSS), employing the Kaplan-Meier method. Cox proportional regression analysis was used to determine the role of selected clinical parameters on the risk of local recurrence, by the univariate and multivariate models. After a median follow-up of 11.2 years (range 5-15 years), 9 pts (11%) developed LR. The LR rates at 5 years and 10 years were 2.4% and 8.2%, respectively. The 5- and 10-year overall survival rates were 98.8% and 91.6%, respectively. The 5- and 10-year breast-cancer-specific survival rates were 100.0% and 99.0%. Late skin and subcutaneous toxicities were generally mild, and cosmetic results were good-excellent for most patients. For the univariate regression analysis, ER positive status (HR; 95% CI, p = 0.021), PgR positive status (HR; 95% CI, p = 0.012), and the aggregate data of positive hormonal status (HR; 95% CI, p = 0.021) were inversely correlated to LR risk. Conversely, a high tumor grade (G3) was directly correlated with the risk of LR (HR; 95% CI, p = 0.048). For the multivariate regression analysis, a high tumor grade (G3) confirmed its negative impact on LR (HR 0.40; 95% CI 0.19-0.75, p = 0.047). Our long-term data demonstrate hypofractionated whole-breast radiotherapy with a concomitant boost to be feasable, effective, and tolerable. Our experience suggests positive hormonal status to be protective with respect to LR risk. A high tumor grade is a risk factor for LR.

Breast Cancer Epidemiology and Contemporary Breast Cancer Care: A Review of the Literature and Clinical Applications

Substantial progress has been made in contemporary breast cancer care, resulting in a consistently declining breast cancer mortality rate and an improvement in quality of life. Advancements include deescalation of therapy in low-risk populations and refining systemic therapy options. Research into molecular biomarkers continues to evolve and holds the promise of achieving the goal of precision medicine, while guidelines for supportive care and survivorship have been created to address the needs of an ever-increasing number of breast cancer survivors. A collaborative, multidisciplinary team approach is essential for patients and survivors to achieve optimal outcomes and enjoy productive high-quality lives. Gynecologists, in particular, play a key role in screening and survivorship care.

Breast Cancer, Version 3.2022, NCCN Clinical Practice Guidelines in Oncology

The therapeutic options for patients with noninvasive or invasive breast cancer are complex and varied. These NCCN Clinical Practice Guidelines for Breast Cancer include recommendations for clinical management of patients with carcinoma in situ, invasive breast cancer, Paget disease, phyllodes tumor, inflammatory breast cancer, and management of breast cancer during pregnancy. The content featured in this issue focuses on the recommendations for overall management of ductal carcinoma in situ and the workup and locoregional management of early stage invasive breast cancer. For the full version of the NCCN Guidelines for Breast Cancer, visit NCCN.org.

Molecular subtypes predict second breast events of ductal carcinoma in situ after breast‐conserving surgery

Purpose

Currently, the prognostic value of molecular subtypes in ductal carcinoma in situ (DCIS) remains unclear. In this study, we explored whether molecular subtypes could predict second breast events (SBEs) in patients after breast‐conserving surgery (BCS).

Methods

From January 2008 to December 2016, 291 DCIS patients treated with BCS were retrospectively analyzed. Patients were classified into four molecular subtypes: luminal A, luminal B, human epidermal growth factor receptor 2 (HER2) overexpression, and triple‐negative breast cancer (TNBC). The SBE incidence was calculated by the competing risk model and compared by Gray's test. The disease‐free survival rates were estimated by the Kaplan–Meier method and compared by the log‐rank test. Prognostic factors were evaluated by univariate and multivariate COX proportional hazards regression model.

Results

With a median follow‐up of 66 months, 12 SBEs were identified. The 5‐year overall SBE incidence of luminal A, luminal B, HER2 overexpression, and TNBC was 2.18%, 4.25%, 15.15%, and 0.00%, respectively. In the univariate analysis, the HER2 overexpression subtype was the predictor of overall (p = 0.005), in situ (p = 0.004), and ipsilateral SBEs (p = 0.008). Patients with endocrine therapy were less likely to develop in situ SBEs (p = 0.039). Additionally, patients with closed (<2 mm) or involved margins were related to a higher risk of contralateral SBEs (p = 0.029). In the multivariate analysis, the HER2 overexpression subtype remained of prognostic values for overall (p = 0.006), in situ (p = 0.029), and ipsilateral SBEs (p = 0.012).

Conclusions

The molecular subtype, especially the HER2 overexpression subtype, was the independent prognostic factor for DCIS patients who underwent BCS.

Addressing the problem of overtreatment in breast cancer

INTRODUCTION

As breast cancer treatment options have multiplied and biologic diversity within breast cancer has been recognized, the use of the same treatment strategies for patients with early-stage and favorable disease, and for those with biologically aggressive disease, has been questioned. In addition, as patient-reported outcome measures have called attention to the morbidity of many common treatments, and as the cost of breast cancer care has continued to increase, reduction in the overtreatment of breast cancer has assumed increasing importance.

AREAS COVERED

Here we review selected aspects of surgery, radiation oncology, and medical oncology for which scientific evidence supports de-escalation for invasive carcinoma and ductal carcinoma in situ, and assess strategies to address overtreatment.

EXPERT OPINION

The problems of breast cancer overtreatment we face today are based on improved understanding of the biology of breast cancer and abandonment of the 'one-size-fits-all' approach. As breast cancer care becomes increasingly complex, and as our knowledge base continues to increase exponentially, these problems will only be magnified in the future. To continue progress, the move must be made from advocating the maximum-tolerated treatment to advocating the minimum-effective one.

Ductal Carcinoma In Situ of Breast: From Molecular Etiology to Therapeutic Management

Ductal carcinoma in situ (DCIS) makes up a majority of noninvasive breast cancer cases. DCIS is a neoplastic proliferation of epithelial cells within the ductal structure of the breast. Currently, there is little known about the progression of DCIS to invasive ductal carcinoma (IDC), or the molecular etiology behind each DCIS lesion or grade. The DCIS lesions can be heterogeneous in morphology, genetics, cellular biology, and clinical behavior, posing challenges to our understanding of the molecular mechanisms by which approximately half of all DCIS lesions progress to an invasive status. New strategies that pinpoint molecular mechanisms are necessary to overcome this gap in understanding, which is a barrier to more targeted therapy. In this review, we will discuss the etiological factors associated with DCIS, as well as the complexity of each nuclear grade lesion. Moreover, we will discuss the possible molecular features that lead to progression of DCIS to IDC. We will highlight current therapeutic management and areas for improvement.

Implicaciones de la pandemia en la radioterapia para el cáncer de mama. Omisión de la radioterapia

La pandemia actual por el nuevo coronavirus (SARS-CoV-2) exige que los sistemas de salud rápidamente adopten medidas encaminadas a mitigar la crisis, lo que implica redistribuir los recursos económicos, sociales y la fuerza laboral, para que aquellos sectores de la población más afectados puedan ser atendidos de forma óptima y oportuna. En los pacientes con carcinoma mamario in situ e invasivo de bajo riesgo, la radioterapia postoperatoria no ofrece ningún beneficio en supervivencia global, lo que hace atractiva la idea de omitir este recurso oncológico. En este artículo, se realizó una revisión de la literatura sobre los criterios para omitir la radioterapia adyuvante en los pacientes con neoplasias mamarias de bajo riesgo. Adicionalmente, se resumen las recomendaciones emitidas por algunas sociedades científicas internacionales durante la contingencia actual, y se analizan determinadas razones por las cuales los médicos se rehúsan a cambiar conductas clínicas que ofrecen ventajas limitadas, muchas veces contrarrestadas por los riesgos y los efectos adversos asociados.

Ductal Carcinoma in Situ: Molecular Changes Accompanying Disease Progression

Ductal carcinoma in situ (DCIS) is a non-obligate precursor of invasive ductal carcinoma (IDC), whereby if left untreated, approximately 12% of patients develop invasive disease. The current standard of care is surgical removal of the lesion, to prevent potential progression, and radiotherapy to reduce risk of recurrence. There is substantial overtreatment of DCIS patients, considering not all DCIS lesions progress to invasive disease. Hence, there is a critical imperative to better predict which DCIS lesions are destined for poor outcome and which are not, allowing for tailored treatment. Active surveillance is currently being trialed as an alternative management practice, but this approach relies on accurately identifying cases that are at low risk of progression to invasive disease. Two DCIS-specific genomic profiling assays that attempt to distinguish low and high-risk patients have emerged, but imperfections in risk stratification coupled with a high price tag warrant the continued search for more robust and accessible prognostic biomarkers. This search has largely turned researchers toward the tumor microenvironment. Recent evidence suggests that a spectrum of cell types within the DCIS microenvironment are genetically and phenotypically altered compared to normal tissue and play critical roles in disease progression. Uncovering the molecular mechanisms contributing to DCIS progression has provided optimism for the search for well-validated prognostic biomarkers that can accurately predict the risk for a patient developing IDC. The discovery of such markers would modernize DCIS management and allow tailored treatment plans. This review will summarize the current literature regarding DCIS diagnosis, treatment, and pathology.

Ipsilateral Recurrence of DCIS in Relation to Radiomics Features on Contrast Enhanced Breast MRI

The purpose of this retrospective study was to investigate the association between ipsilateral recurrence of ductal carcinoma in situ (DCIS) and radiomics features from DCIS and contralateral normal breast on contrast enhanced breast MR imaging. A total of 163 patients with DCIS who underwent preoperative MR imaging between January 2010 and December 2014 were included (training cohort; n = 117, validation cohort; n = 46). Radiomics features were extracted from whole tumor volume of DCIS on early dynamic T1-subtraction images and from the contralateral normal breast on precontrast T1 and early dynamic T1-subtraction images. After feature selection, a Rad-score was established by LASSO Cox regression model. Performance of Rad-score was evaluated by the receiver operating characteristic (ROC) curve and Kaplan Meier curve with log rank test. The Rad-score was significantly associated with ipsilateral recurrence free survival (RFS). The low-risk group with a low Rad-score showed higher ipsilateral RFS than the high-risk group with a high Rad-score in both training and validation cohorts (p < 0.01). The Rad-score based on radiomics features from DCIS and contralateral normal breast on breast MR imaging showed the potential for prediction of ipsilateral RFS of DCIS.

Rural-urban differences in secular trends of locoregional treatment for ductal carcinoma in situ: A patterns of care analysis

Precis

Omission of PORT following BCS remains high among rural patients despite evidence that PORT leads to a significant reduction in the risk of local recurrence. Further research is needed to examine the impact of rural residence on treatment choices and develop methods to ensure equitable care among all breast cancer patients.

Background

Despite national guidelines, debate exists among clinicians regarding the optimal approach to treatment for patients diagnosed with ductal carcinoma in situ (DCIS). While regional variation in practice patterns has been well documented, population‐based information on rural–urban treatment differences is lacking.

Methods

Data from the SEER Patterns of Care studies were used to identify women diagnosed with histologically confirmed DCIS who underwent cancer‐directed surgery in the years 1991, 1995, 2000, 2005, 2010, and 2015. Adjusted odds ratios (aORs) and 95% confidence intervals (CIs) were estimated using weighted multivariable logistic regression to evaluate cancer‐directed surgery and use of post‐operative radiation therapy (PORT).

Results

Of the 3337 patients who met inclusion criteria, 27% underwent mastectomy, 26% underwent breast‐conserving surgery (BCS) without PORT, and 47% underwent BCS with PORT. After adjustment for other covariates, there was no difference in the likelihood of receiving mastectomy between rural and urban patients (aOR = 0.65; 95% CI 0.37–1.14). However, rural residents were more likely than urban residents to have mastectomy during 1991/1995 (aOR = 1.78; 95% CI 1.09–2.91; p_interaction = 0.022). Across all diagnosis years, patients residing in rural areas were less likely to receive PORT following BCS compared to urban patients (aOR = 0.35; 95% CI 0.18–0.67).

Conclusions

Omission of PORT following BCS remains high among rural patients despite evidence that PORT leads to a significant reduction in the risk of local recurrence. Further research is needed to examine the impact of rural residence on treatment choices and develop methods to ensure equitable care among all breast cancer patients.

Histopathological growth distribution of ductal carcinoma in situ: tumor size is not "one size fits all"

BACKGROUND

Ductal carcinoma in situ (DCIS) is a group of preinvasive breast neoplasms. Studies have shown excellent survival among patients with lumpectomy-amenable disease. Patients requiring mastectomy have been less well characterized. We aim to characterize this cohort and identify whether growth distribution pattern is associated with sentinel lymph node involvement at time of surgery or subsequent development of metastatic disease.

METHODS

Patients were identified using local cancer registry data and were chart reviewed using electronic medical records. Growth pattern was classified as unifocal, multifocal, or diffuse. Chi-squared, Analysis of Variance (ANOVA), and Kaplan-Meier analyses were performed.

RESULTS

Two hundred and twenty-six patients were identified with median age at diagnosis 49 and follow up 7.1 years. 42 had unifocal, 51 had multifocal and 20 had diffuse lesions. 3/20 patients with diffuse type lesions developed subsequent distant metastatic disease, while none of the patients with unifocal or multifocal lesions did. 1/20 patients with diffuse and 2/51 with multifocal disease had sentinel lymph node involvement (SLNI) at surgery. Tumor extent was not associated with sentinel lymph node involvement or distant metastatic disease (P=0.2, Kaplan-Meier analysis) but growth pattern was (P=0.01). It was also associated on Kaplan-Meier with development of distant metastatic disease alone (P=0.01).

CONCLUSIONS

Patients with diffuse growth pattern DCIS were more likely to have SLNI or development of distant metastatic disease. Our findings suggest that patients with diffuse type lesions are at greater risk of metastatic disease and therefore breast cancer death from DCIS. Optimal therapy for these patients will need further elucidation.

Underestimation Rate in the Percutaneous Diagnosis of Radial Scar/Complex Sclerosing Lesion of the Breast: Systematic Review

OBJECTIVE

 To evaluate the underestimation rate in breast surgical biopsy after the diagnosis of radial scar/complex sclerosing lesion through percutaneous biopsy.

DATA SOURCES

 A systematic review was performed following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) recommendations. The PubM: ed, SciELO, Cochrane, and Embase databases were consulted, with searches conducted through November 2020, using specific keywords (radial scar OR: complex sclerosing lesion, breast cancer, anatomopathological percutaneous biopsy AND/OR: surgical biopsy).

DATA COLLECTION

 Study selection was conducted by two researchers experienced in preparing systematic reviews. The eight selected articles were fully read, and a comparative analysis was performed.

STUDY SELECTION

 A total of 584 studies was extracted, 8 of which were selected. One of them included women who had undergone a percutaneous biopsy with a histological diagnosis of radial scar/complex sclerosing lesion and subsequently underwent surgical excision; the results were used to assess the underestimation rate of atypical and malignant lesions.

DATA SYNTHESIS

 The overall underestimation rate in the 8 studies ranged from 1.3 to 40% and the invasive lesion underestimation rate varied from 0 to 10.5%.

CONCLUSION

 The histopathological diagnosis of a radial scar/complex sclerosing lesion on the breast is not definitive, and it may underestimate atypical and malignant lesions, which require a different treatment, making surgical excision an important step in diagnostic evaluation.

Type of Recurrence, Cause of Death and Second Neoplasms among 737 Patients with Ductal Carcinoma In Situ of the Breast—15-Year Follow-Up

Simple Summary

A retrospective analysis of 737 consecutive DCIS patients with a 15-year follow-up was carried out. Sixty-six recurrences (42% DCIS, 58% invasive) were reported: 61 in the breast and 5 outside the breast. 79% of local recurrences were true recurrences. The highest number of recurrences was reported in patients after local excision without radiotherapy despite the fact that it was the lowest-risk group. Deaths due to DCIS progression were reported in 0.5% of all patients and in 10.5% of patients with invasive recurrences. The majority of deaths were linked to the age of the patients or other diseases, including other neoplasms.

Abstract

Aim: To assess the outcomes of 737 consecutive patients with DCIS, with particular attention to the type of recurrences, other malignancies and causes of deaths. Material and Methods: A retrospective analysis of 737 consecutive DCIS patients treated in one institution in the years 1996–2011 was carried out. The cumulative recurrence risk, DFS, OS depending on the method of treatment (mastectomy, breast-conserving treatment (BCT), breast-conserving surgery (BCS)) and cause of death were assessed. Results: Sixty-six recurrences (42% DCIS, 58% invasive) were reported: 61 in the breast and 5 outside the breast. The cumulative recurrence risk after a 15-year observation after mastectomy, BCT and BCS was 3.2%, 19.5% and 31.2%, respectively (p < 0.001). The 15-year DFS after mastectomy, BCT and BCS was 72%, 65% and 48%, respectively (p < 0.001). The 15-year OS after mastectomy, BCT and BCS was 75%, 83% and 70%, respectively (p = 0.329). Deaths due to DCIS progression were reported in four (0.5%) of the overall patients and in 10.5% of patients with invasive recurrences. The majority of deaths were linked to the age of the patients or other diseases, including other neoplasms, but not DCIS. Conclusions: The highest number of recurrences was reported in patients after BCS, despite the fact that it was the lowest-risk group. In total, 79% of local recurrences were true recurrences and 58% were invasive recurrences. Local recurrences were effectively treated without an influence on the OS. The percentage of deaths due to DCIS was low and mainly concerned patients with locoregional and distant failure.

Investigating the effectiveness of adjuvant therapy for patients with hormone receptor-positive ductal carcinoma in situ

BACKGROUND

This study compared the recurrence risk of single versus dual adjuvant radiotherapy (RT) and hormonal therapy (HT) following breast-conserving surgery (BCS) in patients with hormone receptor-positive ductal carcinoma in situ (DCIS).

METHODS

This retrospective cohort study used the Taiwan Cancer Registry database linking to the Taiwan National Health Insurance data from 2011 to 2016. We compared the recurrence risk between BCS-based regimens in Cox regressions and presented as adjusted hazard ratio (HR) and 95% confidence interval (95%CI).

RESULTS

The 1,836 study cohort with a low-to-intermediate risk of recurrence was grouped into BCS alone (6.1%), BCS+RT (6.2%), BCS+HT (23.4%) and BCS+HT+RT (64.3%) according to the initial treatments. During the follow-up (median: 3.3 years), the highest 5-year recurrence-free survival rate was in BCS+RT (94.1%) group and followed by BCS+HT+RT (92.8%), BCS+HT (87.4%) and BCS alone (84.9%). Of the single adjuvant therapies, RT was more effective than HT. Both BCS+HT (HR: 1.52, 95%CI: 0.99-2.35) and BCS+RT (HR: 1.10, 95%CI: 0.50-2.41) did not significantly increase recurrence risk comparing against the BCS+HT+RT group.

CONCLUSION

Single adjuvant demonstrated a similar subsequent recurrence risk with dual adjuvant. This study supports the proposition to de-escalate adjuvant treatments in patients with low-to-intermediate risk of DCIS recurrence.

Preneoplastic Low-Risk Mammary Ductal Lesions (Atypical Ductal Hyperplasia and Ductal Carcinoma In Situ Spectrum): Current Status and Future Directions

Intraepithelial mammary ductal neoplasia is a spectrum of disease that varies from atypical ductal hyperplasia (ADH), low-grade (LG), intermediate-grade (IG), to high-grade (HG) ductal carcinoma in situ (DCIS). While ADH has the lowest prognostic significance, HG-DCIS carries the highest risk. Due to widely used screening mammography, the number of intraepithelial mammary ductal neoplastic lesions has increased. The consequence of this practice is the increase in the number of patients who are overdiagnosed and, therefore, overtreated. The active surveillance (AS) trials are initiated to separate lesions that require active treatment from those that can be safely monitored and only be treated when they develop a change in the clinical/radiologic characteristics. At the same time, the natural history of these lesions can be evaluated. This review aims to evaluate ADH/DCIS as a spectrum of intraductal neoplastic disease (risk and histomorphology); examine the controversies of distinguishing ADH vs. DCIS and the grading of DCIS; review the upgrading for both ADH and DCIS with emphasis on the variation of methods of detection and the definitions of upgrading; and evaluate the impact of all these variables on the AS trials.

Updates on breast biomarkers

Recent advancements in breast cancer treatment have ushered in a new era of precision medicine. Novel trials have led to the approval of a growing list of personalized therapies and corresponding biomarkers. These advancements have shifted the pathologist's practice into a leading role in the management breast cancer. Understanding the complex algorithms and diagnostic modalities used to assess predictive and prognostic biomarkers is central for quality oncology care. ER and HER2 subcategorize breast cancers into treatment groups under which different biomarkers and therapies are indicated, while they also serve as predictive biomarkers for specific targeted treatments. This review will cover the evolution and latest updates of the CAP/ASCO guidelines relevant to these two important biomarkers in breast cancer. Still evolving concepts such as HER2 heterogeneity, HER2 "low," and HER2-mutated cancers have the potential to continue to change HER2 testing in breast cancers. In addition to ER and HER2, biomarkers used in specific clinical scenarios will be covered. In early-stage ER-positive/HER2-negative disease, multi-gene expression panels (such as OncotypeDX) have emerged as the new standard biomarker when determining if chemotherapy should be added to endocrine therapy. In the more aggressive ER-negative/HER2-positive or triple negative early-stage breast cancers, response to neoadjuvant therapy has proved to be a useful biomarker to help determine if additional therapy should be added for patients with an incomplete response. Ki67 has also recently emerged as a marker that can be used to identify the highest risk ER-positive and HER2-negative cancers if considering adding a cell cycle inhibitor (abemaciclib) to endocrine therapy. Importantly, in the metastatic setting, numerous predictive biomarkers have emerged, including recommendations for germline BRCA mutation testing for all metastatic patients (to determine if PARP inhibitor therapy is an option) and other ER-/HER2-dependent biomarkers such as PD-L1 (for potential immunotherapy in triple negative patients) and PIK3CA mutation status (for potential PI3K inhibitor therapy in ER-positive metastatic patients). Other less common biomarkers of targeted therapy options (e.g., MSI/MMR, TMB, NTRK) as well as comprehensive genomic profiling to identify uncommon targets are also available in the metastatic setting to determine additional treatment options.

Low-risk DCIS. What is it? Observe or excise?

The issue of overdiagnosis and overtreatment of lesions detected by breast screening mammography has been debated in both international media and the scientific literature. A proportion of cancers detected by breast screening would never have presented symptomatically or caused harm during the patient's lifetime. The most likely (but not the only) entity which may represent those overdiagnosed and overtreated is low-grade ductal carcinoma in situ (DCIS). In this article, we address what is understood regarding the natural history of DCIS and the diagnosis and prognosis of low-grade DCIS. However, low cytonuclear grade disease may not be the totality of DCIS that can be considered of low clinical risk and we outline the issues regarding active surveillance vs excision of low-risk DCIS and the clinical trials exploring this approach.

Large and diffuse ductal carcinoma in situ: potentially lethal subtypes of "preinvasive" disease

PURPOSE

Trials for DCIS have not explored whether outcomes for patients with large disease burden requiring mastectomy are comparable to those of patients with lumpectomy-amenable disease. We aim to identify whether patients with DCIS larger than 5 cm and diffuse-type DCIS differ in breast cancer mortality (BCM) from patients with disease less than 5 cm.

METHODS

Patients diagnosed with DCIS in the SEER program were assessed to identify factors prognostic of breast-cancer-specific survival using competing risks regression.

RESULTS

44,849 patients met criteria for the cumulative incidence estimate. On competing risks cumulative incidence approximation, the 10-year estimate for BCM for each group was 1.3%, 1.3%, 2.3%, and 5.1%, respectively, and the difference among groups was significant (p = 0.017). On competing risks regression of patients with known covariates, both diffuse-type disease and disease larger than 5 cm (hazard ratio [HR] = 6.2 and 1.7, p = 0.013 and p = 0.042, respectively) were associated with increased risk of BCM. After matching, DCIS > 5 cm and diffuse disease were associated with increased BCM relative to disease < 5 cm (HR = 1.69, p = 0.04). Among patients undergoing mastectomy for disease larger than 5 cm or diffuse disease, the 10-year cumulative incidence for BCM was 0.5% among patients undergoing bilateral mastectomy and 2.4% for patients undergoing unilateral mastectomy.

CONCLUSION

Patients with large and diffuse DCIS represent uncommon but poorly studied DCIS subgroups with worse prognoses than patients with disease smaller than 5 cm. Further studies are needed to elucidate the appropriate treatment for these patients.

Assessment of the usefulness of prognostic Van Nuys Prognostic Index in the treatment in ductal carcinoma in situ in 15-year observation

Ductal carcinoma in situ, a marginal fraction of the mammary gland diseases, is recognized in 25% of breast cancers detected with mammographic screening. The aim of the study was to assess the prognostic value of Van Nuys Prognostic Index, serving to determine the method of treatment according to the recurrence risk. From the 737 of cases of DCIS detection patients treated in our department in the years 1996–2011. The remaining 525 patients whose treatment began from excision of local DCIS and whose further course of treatment was determined after histopathological examination, who were left for observation, treated with lumpectomy and radiotherapy or mastectomy, were qualified for the assessment of mentioned index (Online Appendix 1- Figure S1). The 5-, 10- and 15- year disease recurrence-free survival for the group of 525 patients was 88%, 74% and 62%, respectively. The percentage of 5-, 10- and 15-year disease recurrence-free survival in patients treated in compliance with the VNP Index in individual risk groups did not differ in a statistically significant way. In the low-risk group the percentage of recurrences after local excision, after 5, 10 and 15 years of observation amounted to 8.8%, 22.8% and 28.8%. In patients from this group, the recurrence risk after breast conserving treatment and mastectomy was 2% and 0%, respectively. VNP Index is not an optimal tool for patients with DCIS. It can be helpful only in some clinically difficult cases as one of methods of assessing the risk of recurrence.

Contralateral breast cancer after curative-intent treatment for ductal carcinoma in situ: Rate and associated clinicopathological and imaging risk factors

PURPOSE

Patients who have ductal carcinoma in situ (DCIS) are undergoing bilateral mastectomy at increasing rates. One of the reasons is to minimize contralateral breast cancer (CBC) risk. The purpose of this study is to determine the rate of and risk factors associated with CBC in women treated for DCIS.

METHODS

A retrospective study was performed of women with DCIS at surgery from 2007 to 2014 who had at least five-year follow-up. Patient attributes, imaging findings, histopathology results, and surgical and long-term outcomes were collected. Features associated with a CBC were assessed with multivariable logistic regression models.

RESULTS

613 women (mean 56 years, range 30-87) with DCIS underwent breast-conserving surgery (BCS) (n = 426), unilateral mastectomy (n = 101), or bilateral mastectomy (n = 86), with mean follow-up of 7.9 years. Of the 527 women who had BCS or unilateral mastectomy, 7.4% (n = 39) developed a CBC (DCIS in 12 and invasive cancer in 27). 4.1% (5/122) of women treated with adjuvant endocrine therapy developed a CBC, compared to 8.4% (34/405) who were not treated (p = .11). Features associated with CBC risk were younger age at menarche (adjusted odds ratio [aOR] of 0.76, p = .03) and low nuclear grade of DCIS (aOR of 5.43 for grade 1 versus 3, p = .01).

CONCLUSION

In women treated for DCIS, the overall rate of CBC was low at 7.4%. Younger age at menarche and low nuclear grade of DCIS had significant associations with higher CBC risk.

Randomized Phase III Trial Evaluating Radiation Following Surgical Excision for Good-Risk Ductal Carcinoma In Situ: Long-Term Report From NRG Oncology/RTOG 9804

PURPOSE

To our knowledge, NRG/RTOG 9804 is the only randomized trial to assess the impact of whole breast irradiation (radiation therapy [RT]) versus observation (OBS) in women with good-risk ductal carcinoma in situ (DCIS), following lumpectomy. Long-term results focusing on ipsilateral breast recurrence (IBR), the primary outcome, are presented here.

PATIENTS AND METHODS

Eligible patients underwent lumpectomy for DCIS that was mammogram detected, size ≤ 2.5 cm, final margins ≥ 3 mm, and low or intermediate nuclear grade. Consented patients were randomly assigned to RT or OBS. Tamoxifen use was optional. Cumulative incidence was used to estimate IBR, log-rank test and Gray's test to compare treatments, and Fine-Gray regression for hazard ratios (HRs).

RESULTS

A total of six hundred thirty-six women were randomly assigned from 1999 to 2006. Median age was 58 years and mean pathologic DCIS size was 0.60 cm. Intention to use tamoxifen was balanced between arms (69%); however, actual receipt of tamoxifen varied, 58% RT versus 66% OBS (P = .05). At 13.9 years' median follow-up, the 15-year cumulative incidence of IBR was 7.1% (95% CI, 4.0 to 11.5) with RT versus 15.1% (95% CI, 10.8 to 20.2) OBS (P = .0007; HR = 0.36; 95% CI, 0.20 to 0.66); and for invasive LR was 5.4% (95% CI, 2.7 to 9.5) RT versus 9.5% (95% CI, 6.0 to 13.9) OBS (P = .027; HR = 0.44; 95% CI, 0.21 to 0.91). On multivariable analysis, only RT (HR = 0.34; 95% CI, 0.19 to 0.64; P = .0007) and tamoxifen use (HR = 0.45; 95% CI, 0.25 to 0.78; P = .0047) were associated with reduced IBR.

CONCLUSION

RT significantly reduced all and invasive IBR for good-risk DCIS with durable results at 15 years. These results are not an absolute indication for RT but rather should inform shared patient-physician treatment decisions about ipsilateral breast risk reduction in the long term following lumpectomy.

Advances and controversies in management of breast ductal carcinoma in situ (DCIS)

Ductal carcinoma in situ (DCIS) is a non-obligate precursor of invasive breast cancer. It accounts for 25% of all breast cancers diagnosed, as a result of the expansion of breast cancer screening and is associated with a high survival rate. DCIS is particularly clinically challenging, due to its heterogeneous pathological and biological traits and its management is continually evolving towards more personalized and less aggressive therapies. This article suggests evidence-based guidelines for proper DCIS clinical management, which should be discussed within a multidisciplinary team in order to propose the most suitable approach in clinical practice, taking into account recent scientific studies. Here we include updated multidisciplinary treatment protocols and techniques in accordance with the most recent contributions published on this topic in the peer-reviewed medical literature, and we outline future perspectives.

The Clinical Utility of DCISionRT® on Radiation Therapy Decision Making in Patients with Ductal Carcinoma In Situ Following Breast-Conserving Surgery

BACKGROUND

The role of radiation therapy (RT) following breast-conserving surgery (BCS) in ductal carcinoma in situ (DCIS) remains controversial. Trials have not identified a low-risk cohort, based on clinicopathologic features, who do not benefit from RT. A biosignature (DCISionRT®) that evaluates recurrence risk has been developed and validated. We evaluated the impact of DCISionRT on clinicians' recommendations for adjuvant RT.

METHODS

The PREDICT study is a prospective, multi-institutional, observational registry in which patients underwent DCISionRT testing. The primary endpoint was to identify the percentage of patients where testing led to a change in RT recommendations.

RESULTS

Overall, 539 women were included in this study. Pre DCISionRT testing, RT was recommended to 69% of patients; however, post-testing, a change in the RT recommendation was made for 42% of patients compared with the pre-testing recommendation; the percentage of women who were recommended RT decreased by 20%. For women initially recommended not to receive an RT pre-test, 35% had their recommendation changed to add RT following testing, while post-test, 46% of patients had their recommendation changed to omit RT after an initial recommendation for RT. When considered in conjunction with other clinicopathologic factors, the elevated DCISionRT score risk group (DS > 3) had the strongest association with an RT recommendation (odds ratio 43.4) compared with age, grade, size, margin status, and other factors.

CONCLUSIONS

DCISionRT provided information that significantly changed the recommendations to add or omit RT. Compared with traditional clinicopathologic features used to determine recommendations for or against RT, the factor most strongly associated with RT recommendations was the DCISionRT result, with other factors of importance being patient preference, tumor size, and grade.

Prognostic and Predictive Value of HER2 Expression in Ductal Carcinoma In Situ: Results from the UK/ANZ DCIS Randomized Trial

PURPOSE

HER2 is overexpressed more frequently in ductal carcinoma in situ (DCIS) than in invasive breast cancer but its prognostic significance and predictive role for radiotherapy has not been clearly established. We investigated the prognostic and predictive value of HER2 overexpression in DCIS.

EXPERIMENTAL DESIGN

HER2 expression was evaluated by IHC using the HercepTest™ in samples from UK/ANZ DCIS trial participants (n = 755) with IHC 3+ expression categorized as HER2 positive for primary analyses. Sensitivity analyses included HER2 categorization as negative (IHC 0,1+), equivocal (IHC 2+), and positive (IHC 3+) and analyses restricted to a nested case-control component where 181 cases (with recurrence) were matched to 362 controls by treatment arm and age.

RESULTS

Two-hundred and forty-five (34.4%) of evaluable 713 samples [181 ipsilateral breast events (IBE)] were HER2 positive. HER2 overexpression was associated with significantly increased risk of IBE [HR = 2.29; 95% confidence interval (95% CI), 1.64-3.14; P < 0.0001] and in situ IBE (DCIS-IBE; HR = 2.90; 95% CI, 1.91-4.40; P < 0.0001), but not of invasive IBE (I-IBE; HR = 1.40; 95% CI, 0.81-2.42; P = 0.23; Pheterogeneity = 0.04). Inclusion of HER2 significantly improved [Δχ2 (1d.f.) 12.25; P = 0.0005] a prognostic model of clinicopathological and treatment variables, HER2 being an independent predictor of IBE (multivariate HR = 1.91; 95% CI, 1.33-2.76; P = 0.0004). Radiotherapy benefit in preventing DCIS-IBE was significantly greater (Pheterogeneity = 0.04) in HER2-positive DCIS (HR = 0.16; 95% CI, 0.07-0.41) compared with HER2-negative DCIS (HR = 0.58; 95% CI, 0.28-1.19).

CONCLUSIONS

HER2 overexpression is associated with significantly increased risk of in situ recurrence and is also predictive of radiotherapy benefit, with greater reductions in in situ but not invasive recurrences in HER2-positive DCIS.

Does margin width impact breast cancer recurrence rates in women with breast conserving surgery for ductal carcinoma in situ?

PURPOSE

Controversy remains regarding the optimal margin width for patients with ductal carcinoma in situ (DCIS) who undergo breast conserving surgery (BCS).

METHODS

Women with a primary DCIS diagnosis were enrolled in a statewide population-based cohort from 1997 to 2006. Patients were surveyed every two years with follow-up data available through 2016. Surgical pathology reports were collected for 559 participants following breast conserving surgery. Multivariable Cox proportional hazard models evaluated relationships between locoregional recurrence (LRR) and margin width in the presence or absence of adjuvant radiation therapy while controlling for age, menopausal status and duration of endocrine therapy use.

RESULTS

The majority of women in this study were over 50yo (74%), 34% had high grade disease, and 77% underwent radiation. The overall LRR rate was 12%. A LRR occurred in 46 women who had radiation (11%) and 23 women who did not undergo radiation (19%). Univariate analysis identified smaller margin width, younger age, premenopausal status, no radiotherapy, and shorter endocrine therapy use associated with LRR. Multivariable models demonstrated that close margins (< 2 mm) were associated with an increased risk of recurrence when compared to margins ≥ 2 mm in width whether women received radiation (HR 1.98 CI 0.87-4.54) or not (HR 1.32 CI 0.27-6.49), but confidence intervals were wide.

CONCLUSIONS

In this study, patients with DCIS and close margins were less likely to experience recurrence after routine re-excision to margins greater than 2 mm.

Hormone Receptor Subtype in Ductal Carcinoma in Situ: Prognostic and Predictive Roles of the Progesterone Receptor

Background

We investigated the prognostic and predictive roles of the hormone receptor (HRc) subtype in patients with ductal carcinoma in situ (DCIS). We focused on identifying the roles of the progesterone receptor (PR) independent of estrogen receptor (ER) status.

Methods

Nationwide data of 12,508 female patients diagnosed with DCIS with a mean follow‐up period of 60.7 months were analyzed. HRc subtypes were classified as ER−/PR−, ER−/PR+, ER+/PR−, and ER+/PR+ based on ER and PR statuses. The Cox proportional hazards model was used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs).

Results

The ER+/PR+ group showed better prognoses than the ER+/PR− and ER−/PR− groups in the patients who received tamoxifen therapy (p = .001 and p = .031, respectively). HRc subtype was an independent prognostic factor (p = .028). The tamoxifen therapy group showed better survival than the patients who did not receive tamoxifen, but only in the ER+/PR+ subgroup (p = .002). Tamoxifen therapy was an independent prognostic factor (HR, 0.619; 95% CI, 0.423 − 0.907; p = .014). PR status was a favorable prognostic factor in patients with DCIS who received tamoxifen therapy (p < .001), and it remained a prognostic factor independent of ER status (HR, 0.576; 95% CI, 0.349 − 0.951; p = .031).

Conclusion

The HRc subtype can be used as both a prognostic and predictive marker in patients with newly diagnosed DCIS. Tamoxifen therapy can improve overall survival in the ER+/PR+ subtype. PR status has significant prognostic and predictive roles independent of ER status. Testing for the PR status in addition to the ER status is routinely recommended in patients with DCIS to determine the HRc subtype in clinical settings.

Implications for Practice

The hormone receptor (HRc) subtype was an independent prognostic factor, and the estrogen receptor (ER)+/progesterone receptor (PR) + subtype showed a better survival in patients with ductal carcinoma in situ (DCIS) who received tamoxifen therapy. PR was an independent prognostic factor independent of ER, and PR was a favorable prognostic factor in patients with DCIS who received tamoxifen therapy. The HRc subtype could be used as both a prognostic and predictive marker in patients with newly diagnosed DCIS. Testing of PR status in addition to ER status is routinely recommended for patients with DCIS to determine the HRc subtype in clinical settings.

This study investigated the prognostic and predictive roles of the hormone receptor subtype in patients with newly diagnosed ductal carcinoma in situ, focusing on the prognostic and predictive values of progesterone receptor status independent of estrogen receptor status. The prognostic effect of tamoxifen therapy was also investigated

Cost-Effectiveness of Adjuvant Treatment for Ductal Carcinoma In Situ

PURPOSE

Ductal carcinoma in situ (DCIS) accounts for 20% of breast cancer cases in the United States and is potentially overtreated, leading to high expenditures and low-value care. We conducted a cost-effectiveness analysis evaluating all adjuvant treatment strategies for DCIS.

METHODS

A Markov model was created with six competing treatment strategies: observation, tamoxifen (TAM) alone, aromatase inhibitor (AI) alone, radiation treatment (RT) alone, RT + TAM, and RT + AI. Baseline recurrence rates were modeled using the NSABP B17 and RTOG 9804 trials for standard-risk and good-risk DCIS, respectively. Relative risk reductions and adverse event rates for each treatment strategy were derived from meta-analyses of large randomized trials. We used a willingness-to-pay threshold of $100,000 in US dollars/quality-adjusted life-year and a lifetime horizon for two cohorts of women, age 40 and 60 years. Comprehensive sensitivity analyses evaluated the robustness of base-case results.

RESULTS

RT alone was cost-effective for patients with standard-risk DCIS, and observation was cost-effective for patients with good-risk DCIS, across both age groups. Strategies including TAM or AI resulted in fewer quality-adjusted life-years than observation, because of the prolonged decrement in quality of life outweighing the modest benefit in ipsilateral risk reduction. In sensitivity analysis, RT alone was cost-effective for age 40, good-risk patients when ipsilateral risk reduction matched that of the RTOG 9804 trial, there was minimal increased risk of contralateral breast secondary malignancy, or there was strong patient willingness to pursue RT.

CONCLUSION

Our findings suggest that cost-effective and clinically optimal treatment strategies are RT alone for standard-risk DCIS and observation for good-risk DCIS, with personalization on the basis of patient age and preference for RT. Hormonal therapy is likely suboptimal for most patients with DCIS.

Comparison of Radiation With or Without Concurrent Trastuzumab for HER2-Positive Ductal Carcinoma In Situ Resected by Lumpectomy: A Phase III Clinical Trial

PURPOSE

Preclinical studies report that trastuzumab (T) can boost radiotherapy (RT) effectiveness. The primary aim of the B-43 trial was to assess the efficacy of RT alone vs concurrent RT plus T in preventing recurrence of ipsilateral breast cancer (IBTR) in women with ductal carcinoma in situ (DCIS).

PATIENTS AND METHODS

Eligibility: Eastern Cooperative Oncology Group (ECOG) performance status 0 or 1, DCIS resected by lumpectomy, known estrogen receptor (ER) and/or progesterone receptor (PgR), and human epidermal growth factor receptor 2 (HER2) status by centralized testing. Whole-breast RT was given concurrently with T. Stratification was by menopausal status, adjuvant endocrine therapy plan, and nuclear grade. Definitive intent-to-treat primary analysis was to be conducted when either 163 IBTR events occurred or all accrued patients were on study ≥ 5 years.

RESULTS

There were 2,014 participants who were randomly assigned. Median follow-up time as of December 31, 2019, was 79.2 months. At primary definitive analysis, 114 IBTR events occurred: RT arm, 63 and RT plus T arm, 51 (hazard ratio [HR], 0.81; 95% CI, 0.56 to 1.17; P value = .26). There were 34 who were invasive: RT arm, 18 and RT plus T arm, 20 (HR, 1.11; 95% CI, 0.59 to 2.10; P value = .71). Seventy-six were DCIS: RT arm, 45 and RT plus T arm, 31 (HR, 0.68; 95% CI, 0.43 to 1.08; P value = .11). Annual IBTR event rates were: RT arm, 0.99%/y and RT plus T arm, 0.79%/y. The study did not reach the 163 protocol-specified events, so the definitive analysis was triggered by all patients having been on study for ≥ 5 years.

CONCLUSION

Addition of T to RT did not achieve the objective of 36% reduction in IBTR rate but did achieve a modest but statistically nonsignificant reduction of 19%. Nonetheless, this trial had negative results. Further exploration of RT plus T is needed in HER2-positive DCIS before its routine delivery in patients with DCIS resected by lumpectomy.

Association of the 12-Gene Breast DCIS Score® Assay With Local Recurrence in Patients With Ductal Carcinoma In Situ Treated on Accelerated Partial Breast Radiotherapy Protocols

Background

The following analysis explores clinicopathologic factors and the 12-gene Breast DCIS Score test result in order to better define an appropriate DCIS (ductal carcinoma in situ) population eligible for APBI (accelerated partial breast radiotherapy).

Methods

This exploratory analysis aimed to retrospectively measure the association between the 12-gene Oncotype DX Breast DCIS Score^® assay (Redwood City, CA) and relevant clinicopathologic factors with locoregional recurrence in a pooled cohort of women treated with local excision and APBI on prospective phase II (NCT01185145) and phase III (NCT01185132) clinical trials. Univariable Cox proportional hazards regression was used to determine whether there was an association between local recurrence and DCIS Score result risk group (≥ 39 vs < 39) and clinicopathologic factors.

Results

This analysis included 104 evaluable patients (n = 18 from NCT01185145 and n = 86 from NCT01185132). The median age was 60 years (range: 40-79). Seventy-nine percent of patients were postmenopausal. The median span of DCIS was 10 mm (range 2-45 mm). Two-thirds of the cohort presented with necrosis (71%). The distribution of DCIS Score^® results ranged from 0 to 82, with 69% of patients having a DCIS Score result < 39. The median follow-up time was 8.2 years in NCT01185145 versus 3.0 years in NCT01185132. There were 6 local ipsilateral breast recurrences. DCIS Score result was significantly associated with local recurrence in univariable modeling, hazard ratio = 10.3 (95% CI 1.7, 198.4); p = 0.010. None of the clinicopathologic characteristics resulted in any significant association with locoregional recurrence.

Conclusion

The Breast DCIS Score assay demonstrated risk stratification in this cohort of patients treated with local excision and APBI pooled from two clinical trials. These results are consistent with those recently published utilizing whole breast radiotherapy. Due to the small number of local recurrence events and limited follow-up time, further investigations are needed to confirm findings.

Prognostic Value of ER and PgR Expression and the Impact of Multi-clonal Expression for Recurrence in Ductal Carcinoma in situ: Results from the UK/ANZ DCIS Trial

PURPOSE

The prognostic value of estrogen receptor (ER)/progesterone receptor (PgR) expression in ductal carcinoma in situ (DCIS) is unclear. We observed multi-clonality when evaluating ER/PgR expression in the UK/ANZ DCIS trial, therefore, we investigated the prognostic role of both uni-clonal and multi-clonal ER/PgR expression in DCIS.

EXPERIMENTAL DESIGN

Formalin-fixed paraffin embedded tissues were collected from UK/ANZ DCIS trial participants (n = 755), and ER/PgR expression was evaluated by IHC in 181 cases (with recurrence) matched to 362 controls by treatment arm and age. Assays were scored by the Allred method and by a newly devised clonal method-analyses categorizing multi-clonal DCIS as ER/PgR-positive as per current practice (Standard) and as ER/PgR-negative (clonal) were performed.

RESULTS

ER expression was multi-clonal in 11% (39/356) of ER-positive (70.6%, 356/504) patients. Ipsilateral breast event (IBE) risk was similarly higher in ER-multi-clonal and ER-negative DCIS as compared with DCIS with uni-clonal ER expression. ER-negative DCIS (clonal) had a higher risk of in situ IBE [OR 4.99; 95% confidence interval (CI), 2.66-9.36; P < 0.0001], but the risk of invasive IBE was not significantly higher (OR 1.72; 95% CI, 0.84-3.53; P = 0.14), P heterogeneity = 0.03. ER was an independent predictor in multivariate analyses (OR 2.66; 95% CI, 1.53-4.61). PgR status did not add to the prognostic information provided by ER.

CONCLUSIONS

ER expression is a strong predictor of ipsilateral recurrence risk in DCIS. ER-positive DCIS with distinct ER-negative clones has a recurrence risk similar to ER-negative DCIS. ER should be routinely assessed in DCIS, and ER scoring should take clonality of expression into account.

Cost-Effectiveness Analysis of No Adjuvant Therapy Versus Partial Breast Irradiation Alone Versus Combined Treatment for Treatment of Low-Risk DCIS: A Microsimulation

PURPOSE

Adjuvant therapy in patients with ductal carcinoma in situ who undergo partial mastectomy remains controversial, particularly for low-risk patients (60 years or older, estrogen-positive, tumor extent < 2.5 cm, grade 1 or 2, and margins ≥ 3 mm). We performed a cost-effectiveness analysis comparing three strategies: no adjuvant treatment after surgery, a five-fraction course of accelerated partial breast irradiation using intensity-modulated radiation therapy (accelerated partial breast irradiation [APBI]-alone), or APBI plus an aromatase inhibitor for 5 years.

MATERIALS AND METHODS

Outcomes including local recurrence, distant metastases, and survival as well as toxicity data were modeled by a patient-level Markov microsimulation model, which were validated against trial data. Costs of treatment and possible adverse events were included from the societal perspective over a lifetime horizon, adjusted to 2019 US dollars and extracted from Medicare reimbursement data. Quality-adjusted life-years (QALYs) were calculated based on utilities extracted from the literature.

RESULTS

No adjuvant therapy was the least costly approach ($5,744), followed by APBI-alone ($11,070); combined therapy was costliest ($16,052). Adjuvant therapy resulted in slightly higher QALYs (no adjuvant, 11.320; APBI-alone, 11.343; and combination, 11.381). In the base case, no treatment was the cost-effective strategy, with an incremental cost-effectiveness ratio of $239,109/QALY for APBI-alone and $171,718/QALY for combined therapy. The incremental cost-effectiveness ratio for combined therapy compared with APBI-alone was $131,949. Probabilistic sensitivity analyses found that no therapy was cost effective (defined as $100,000/QALY of lower) in 63% of trials, APBI-alone in 19%, and the combination in 18%.

CONCLUSION

No adjuvant therapy represents the most cost-effective approach for postmenopausal women 60 years or older who receive partial mastectomy for low-risk ductal carcinoma in situ.

Ductal Carcinoma in Situ in Young Women: Increasing Rates of Mastectomy and Variability in Endocrine Therapy Use

BACKGROUND

Young women with ductal carcinoma in situ (DCIS) represent a unique cohort given considerations for future risk reduction and treatment effects on fertility and quality of life. We evaluated national patterns of care in the treatment of young women and the impact of those treatments on overall survival (OS).

METHODS

Women younger than 50 years of age diagnosed with pure DCIS from 2004 to 2016 in the National Cancer Database (NCDB) were identified. Clinical, demographic, and choice of local therapy are summarized and trended over time. OS was analyzed using Cox proportional hazard models.

RESULTS

A total of 52,150 women were identified, and the most common surgical treatment was breast-conservation surgery (BCS; 59%). Bilateral mastectomy (BM) increased in frequency from 2004 to 2016 (11-27%; p < 0.001). In women < 40 years of age, BM (39%) surpassed BCS (35%) in 2010 with a continued upward trend. On multivariable analysis, no OS benefit of BM (hazard ratio [HR] 0.99, p = 0.90) or unilateral mastectomy (UM; HR 0.98, p = 0.80) was observed when compared with BCS + radiation therapy (RT). Inferior OS was seen with BCS, Black race, estrogen receptor (ER)-negative, and tumor ≥ 2.5 cm (p ≤ 0.006). In ER+ patients, there was a significant difference in endocrine therapy (ET) use between BM (11%), UM (33%), and BCS (28%) compared with BCS + RT (64%, p < 0.001).

CONCLUSION

The use of BM for DCIS is increasing in younger patients and now exceeds breast-conservation approaches in women < 40 years of age with no evidence of improved OS. Among ER+ patients, the rates of ET are lower in the BM, UM, and BCS-alone groups compared with BCS + RT.

Improving DCIS diagnosis and predictive outcome by applying artificial intelligence

Breast ductal carcinoma in situ (DCIS) is a preinvasive lesion that is considered to be a precursor to invasive breast cancer. Nevertheless, not all DCIS will progress to invasion. Current histopathological classification systems are unable to predict which cases will or will not progress, and therefore many women with DCIS may be overtreated. Artificial intelligence (AI) image-based analysis methods have potential to identify and analyze novel features that may facilitate tumor identification, prediction of disease outcome and response to treatment. Indeed, these methods prove promising for accurately identifying DCIS lesions, and show potential clinical utility in the therapeutic stratification of DCIS patients. Here, we review how AI techniques in histopathology may aid diagnosis and clinical decisions in regards to DCIS, and how such techniques could be incorporated into clinical practice.

Impact of adjuvant endocrine therapy on prognosis in small hormone receptor-positive, HER2-negative early breast cancer

BACKGROUND

The efficacy of adjuvant endocrine therapy for hormone receptor-positive breast cancer has been previously established. However, significant adverse events related to endocrine therapy cannot be ignored. T1 breast cancer is expected to have a good prognosis. Therefore, adjuvant endocrine therapy for T1a breast cancer patients is controversial. Thus, in this study, we examined the effect of endocrine therapy on the prognosis of T1N0 hormone receptor-positive, HER2-negative breast cancer patients in each tumor size group, and re-considered the application of endocrine therapy.

METHODS

We retrospectively obtained clinical and pathological data from medical records of 7635 patients who underwent surgery for breast cancer at Aichi Cancer Hospital between January 2000 and December 2017. The primary end point of our analysis was disease-free survival (DFS). The secondary end points were distant disease-free survival (DDFS), overall survival (OS), and breast cancer-specific survival (BCSS). The log-rank test, cumulative survival generated curves with Kaplan-Meier methods and the hazard ratio (HR) calculated with a Cox regression model were used to assess the effects of endocrine therapy on prognosis.

RESULTS

The 5-year DFS was worse in the non-endocrine therapy (non-ET) group (78%) than the endocrine therapy (ET) group (95%) in the T1c population (p < 0.001, HR 0.25). However, there was no statistically significant difference in DFS between the ET and the non-ET groups in T1a (ET 96% vs non-ET 93%, p = 0.9314, HR 0.94) and T1b (ET 96% vs non-ET 93%, p = 0.1481HR 0.53) breast cancer. The OS, DDFS, and BCSS of the patients also showed that endocrine therapy was associated with improvement of the prognosis in the T1c group, but not in the T1a and T1b groups.

CONCLUSIONS

Adjuvant endocrine therapy may be essential for T1c breast cancer patients. In contrast, this therapy should be discussed for T1a and T1b luminal breast cancer patients under some circumstances, such as suffering from adverse events.