Histopathological risk factors for ipsilateral breast events after breast conserving treatment for ductal carcinoma in situ of the breast – Results from the Swedish randomised trial

Oncotype DX Breast DCIS Score® Test: Impact on Radiotherapy Recommendations and Patient Decisional Anxiety

AIMS

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.

MATERIAL AND METHODS

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.

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.

CONCLUSION

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.

Association of DCIS size and margin status with risk of developing breast cancer post-treatment: multinational, pooled cohort study

OBJECTIVE

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.

DESIGN

Multinational, pooled cohort study.

SETTING

Four large international cohorts.

PARTICIPANTS

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.

MAIN OUTCOME MEASURES

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.

CONCLUSIONS

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.

Analytical validation of the 7-gene biosignature for prediction of recurrence risk and radiation therapy benefit for breast ductal carcinoma in situ

Purpose

Ductal carcinoma in situ (DCIS), is a noninvasive breast cancer, representing 20-25% of breast cancer diagnoses in the USA. Current treatment options for DCIS include mastectomy or breast-conserving surgery (BCS) with or without radiation therapy (RT), but optimal risk-adjusted treatment selection remains a challenge. Findings from past and recent clinical trials have failed to identify a 'low risk' group of patients who do not benefit significantly from RT after BCS. To address this unmet need, a DCIS biosignature, DCISionRT (PreludeDx, Laguna Hills, CA), was developed and validated in multiple cohorts. DCISionRT is a molecular assay with an algorithm reporting a recurrence risk score for patients diagnosed with DCIS intended to guide DCIS treatment. In this study, we present results from analytical validity, performance assessment, and clinical performance validation and clinical utility for the DCISionRT test comprised of multianalyte assays with algorithmic analysis.

Methods

The analytical validation of each molecular assay was performed based on the Clinical and Laboratory Standards Institute (CLSI) guidelines Quality Assurance for Design Control and Implementation of Immunohistochemistry Assays and the College of American Pathologists/American Society of Clinical Oncology (CAP/ASCO) recommendations for analytic validation of immunohistochemical assays.

Results

The analytic validation showed that the molecular assays that are part of DCISionRT test have high sensitivity, specificity, and accuracy/reproducibility (≥95%). The analytic precision of the molecular assays under controlled non-standard conditions had a total standard deviation of 6.6 (100-point scale), where the analytic variables (Lot, Machine, Run) each contributed <1% of the total variance. Additionally, the precision in the DCISionRT test result (DS) had a 95%CI ≤0.4 DS units under controlled non-standard conditions (Day, Lot, and Machine) for molecular assays over a wide range of clinicopathologic factor values. Clinical validation showed that the test identified 37% of patients in a low-risk group with a 10-year invasive IBR rate of ~3% and an absolute risk reduction (ARR) from RT of 1% (number needed to treat, NNT=100), while remaining patients with higher DS scores (elevated-risk) had an ARR for RT of 9% (NNT=11) and 96% clinical sensitivity for RT benefit.

Conclusion

The analytical performance of the PreludeDx DCISionRT molecular assays was high in representative formalin-fixed, paraffin-embedded breast tumor specimens. The DCISionRT test has been analytically validated and has been clinically validated in multiple peer-reviewed published studies.

Analysis of Local Recurrence Risk in Ductal Carcinoma In Situ and External Validation of the Memorial Sloan Kettering Cancer Center Nomogram

BACKGROUND

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.

METHODS

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.

RESULTS

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).

CONCLUSIONS

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).

Novel markers in breast pathology

Breast pathology is an ever-expanding database of information which includes markers, or biomarkers, that detect or help treat the disease as prognostic or predictive information. This review focuses on these aspects of biomarkers which are grounded in immunohistochemistry, liquid biopsies and next-generation sequencing.

Prognostic Risk Assessment and Prediction of Radiotherapy Benefit for Women with Ductal Carcinoma In Situ (DCIS) of the Breast, in a Randomized Clinical Trial (SweDCIS)

Simple Summary

Despite clinical advancements in the diagnosis and treatment of DCIS, tailoring individual treatment for women diagnosed with DCIS remains an unmet clinical need. Definitive predictive tools that can predict who will or not benefit from radiation therapy (RT) after breast conserving surgery (BCS) remains elusive. Here, we used a prospective–retrospective design to validate DCISionRT^®, using data from the SweDCIS randomized clinical trial. DCISionRT identified women with elevated recurrence risk who benefited substantially from RT after BCS. In addition, the test identified women with low recurrence risk and little benefit from RT. These results support our conclusions that knowledge of the individual risk and benefit from RT provided by the test can help clinicians and patients make individualized treatment decisions for women diagnosed with DCIS.

Abstract

Prediction of radiotherapy (RT) benefit after breast-conserving surgery (BCS) for DCIS is crucial. The aim was to validate a biosignature, DCISionRT^®, in the SweDCIS randomized trial. Women were randomly assigned to RT or not after BCS, between 1987 and 2000. Tumor blocks were collected, and slides were sent to PreludeDx^TM for testing. In 504 women with complete data and negative margins, DCISionRT divided 52% women into Elevated (DS > 3) and 48% in Low (DS ≤ 3) Risk groups. In the Elevated Risk group, RT significantly decreased relative 10-year ipsilateral total recurrence (TotBE) and 10-year ipsilateral invasive recurrence (InvBE) rates, HR 0.32 and HR 0.24, with absolute decreases of 15.5% and 9.3%. In the Low Risk group, there were no significant risk differences observed with radiotherapy. Using a cutoff of DS > 3.0, the test was not predictive for RT benefit (p = 0.093); however, above DS > 2.8 RT benefit was greater for InvBE (interaction p = 0.038). Recurrences at 10 years without radiotherapy increased significantly per 5 DS units (TotBE HR:1.5 and InvBE HR:1.5). Continuous DS was prognostic for TotBE risk although categorical DS did not reach significance. Absolute 10-year TotBE and InvBE risks appear sufficiently different to indicate that DCISionRT can aid physicians in selecting individualized adjuvant DCIS treatment strategies. Further analyses are planned in combined cohorts to increase statistical power.

Breast adipocyte size associates with ipsilateral invasive breast cancer risk after ductal carcinoma in situ

Although ductal carcinoma in situ (DCIS) is a non-obligate precursor to ipsilateral invasive breast cancer (iIBC), most DCIS lesions remain indolent. Hence, overdiagnosis and overtreatment of DCIS is a major concern. There is an urgent need for prognostic markers that can distinguish harmless from potentially hazardous DCIS. We hypothesised that features of the breast adipose tissue may be associated with risk of subsequent iIBC. We performed a case-control study nested in a population-based DCIS cohort, consisting of 2658 women diagnosed with primary DCIS between 1989 and 2005, uniformly treated with breast conserving surgery (BCS) alone. We assessed breast adipose features with digital pathology (HALO®, Indica Labs) and related these to iIBC risk in 108 women that developed subsequent iIBC (cases) and 168 women who did not (controls) by conditional logistic regression, accounting for clinicopathological and immunohistochemistry variables. Large breast adipocyte size was significantly associated with iIBC risk (odds ratio (OR) 2.75, 95% confidence interval (95% CI) = 1.25-6.05). High cyclooxygenase (COX)-2 protein expression in the DCIS cells was also associated with subsequent iIBC (OR 3.70 (95% CI = 1.59-8.64). DCIS with both high COX-2 expression and large breast adipocytes was associated with a 12-fold higher risk (OR 12.0, 95% CI = 3.10-46.3, P < 0.001) for subsequent iIBC compared with women with smaller adipocyte size and low COX-2 expression. Large breast adipocytes combined with high COX-2 expression in DCIS is associated with a high risk of subsequent iIBC. Besides COX-2, adipocyte size has the potential to improve clinical management in patients diagnosed with primary DCIS.

A Clinical Decision Support System for Predicting Invasive Breast Cancer Recurrence: Preliminary Results

The mortality associated to breast cancer is in many cases related to metastasization and recurrence. Personalized treatment strategies are critical for the outcomes improvement of BC patients and the Clinical Decision Support Systems can have an important role in medical practice. In this paper, we present the preliminary results of a prediction model of the Breast Cancer Recurrence (BCR) within five and ten years after diagnosis. The main breast cancer-related and treatment-related features of 256 patients referred to Istituto Tumori “Giovanni Paolo II” of Bari (Italy) were used to train machine learning algorithms at the-state-of-the-art. Firstly, we implemented several feature importance techniques and then we evaluated the prediction performances of BCR within 5 and 10 years after the first diagnosis by means different classifiers. By using a small number of features, the models reached highly performing results both with reference to the BCR within 5 years and within 10 years with an accuracy of 77.50% and 80.39% and a sensitivity of 92.31% and 95.83% respectively, in the hold-out sample test. Despite validation studies are needed on larger samples, our results are promising for the development of a reliable prognostic supporting tool for clinicians in the definition of personalized treatment plans.

Validation of a Ductal Carcinoma In Situ Biomarker Profile for Risk of Recurrence after Breast-Conserving Surgery with and without Radiotherapy

PURPOSE

A major challenge in ductal carcinoma in situ (DCIS) treatment is selection of the most appropriate therapeutic approach for individual patients. We conducted an external prospective-retrospective clinical validation of a DCIS biologic risk signature, DCISionRT, in a population-based observational cohort of women diagnosed with DCIS and treated with breast-conserving surgery (BCS).

EXPERIMENTAL DESIGN

Participants were 455 health plan members of Kaiser Permanente Northwest diagnosed with DCIS and treated with BCS with or without radiotherapy from 1990 to 2007. The biologic signature combined seven protein tumor markers assessed in formalin-fixed, paraffin-embedded tumor tissue with four clinicopathologic factors to provide a DCISionRT test result, termed decision score (DS). Cox regression and Kaplan-Meier analysis were used to measure the association of the DS, continuous (linear) or categorical (DS ≤ 3 vs. DS > 3), and subsequent total ipsilateral breast events and invasive ipsilateral breast events at least 6 months after initial surgery.

RESULTS

In Cox regression, the continuous and categorical DS variables were positively associated with total and invasive breast event risk after adjustment for radiotherapy. In a subset analysis by treatment group, categorical Kaplan-Meier analyses showed at least 2-fold differences in 10-year risk of total breast events between the elevated-risk and low-risk DS categories.

CONCLUSIONS

In this first external validation study of the DCISionRT test, the DS was prognostic for the risk of later breast events for women diagnosed with DCIS, following BCS.

Risk of Contralateral Breast Cancer in Women with Ductal Carcinoma In Situ Associated with Synchronous Ipsilateral Lobular Carcinoma In Situ

BACKGROUND

Lobular carcinoma in situ (LCIS) is a risk factor for breast cancer, but the effect of LCIS found in association with ductal carcinoma in situ (DCIS) is unknown. In this study, we compared contralateral breast cancer (CBC) and ipsilateral breast tumor recurrence (IBTR) rates among women with DCIS with or without synchronous ipsilateral LCIS treated with breast-conserving surgery (BCS).

METHODS

DCIS patients undergoing BCS from 2000 to 2011 with a contralateral breast at risk were stratified by the presence or absence of synchronous ipsilateral LCIS with the index DCIS (DCIS + LCIS vs. DCIS). Those with contralateral, bilateral, or prior ipsilateral LCIS were excluded. Associations of patient, tumor, and treatment factors with CBC and IBTR were evaluated.

RESULTS

Of 1888 patients identified, 1475 (78%) had DCIS and 413 (22%) had DCIS + LCIS. At median follow-up of 7.2 (range 0-17) years, 307 patients had a subsequent first breast event; 207 IBTR and 100 CBC. The 10-year cumulative incidence of IBTR was similar in both groups: 15.0% vs. 14.2% (log-rank, p = 0.8) for DCIS + LCIS vs. DCIS, respectively. The 10-year cumulative incidence of CBC was greater in the DCIS + LCIS group: 10.9% vs. 6.1% for DCIS (log-rank, p < 0.001). After adjustment for other factors, CBC risk remained higher in DCIS + LCIS compared with DCIS (hazard ratio 2.06, 95% confidence interval 1.36-3.11, p = 0.001); there was no significant difference in IBTR risk.

CONCLUSIONS

Compared with DCIS alone, DCIS + LCIS is associated with similar IBTR risk but double the risk of CBC. This finding should inform treatment decisions, in particular regarding endocrine therapy for risk reduction.

Predictors of an Invasive Breast Cancer Recurrence after DCIS: A Systematic Review and Meta-analyses

We performed a systematic review with meta-analyses to summarize current knowledge on prognostic factors for invasive disease after a diagnosis of ductal carcinoma in situ (DCIS). Eligible studies assessed risk of invasive recurrence in women primarily diagnosed and treated for DCIS and included at least 10 ipsilateral-invasive breast cancer events and 1 year of follow-up. Quality in Prognosis Studies tool was used for risk of bias assessment. Meta-analyses were performed to estimate the average effect size of the prognostic factors. Of 1,781 articles reviewed, 40 articles met the inclusion criteria. Highest risk of bias was attributable to insufficient handling of confounders and poorly described study groups. Six prognostic factors were statistically significant in the meta-analyses: African-American race [pooled estimate (ES), 1.43; 95% confidence interval (CI), 1.15-1.79], premenopausal status (ES, 1.59; 95% CI, 1.20-2.11), detection by palpation (ES, 1.84; 95% CI, 1.47-2.29), involved margins (ES, 1.63; 95% CI, 1.14-2.32), high histologic grade (ES, 1.36; 95% CI, 1.04-1.77), and high p16 expression (ES, 1.51; 95% CI, 1.04-2.19). Six prognostic factors associated with invasive recurrence were identified, whereas many other factors need confirmation in well-designed studies on large patient numbers. Furthermore, we identified frequently occurring biases in studies on invasive recurrence after DCIS. Avoiding these common methodological pitfalls can improve future study designs.

Prolyl-4-hydroxylase Α subunit 2 (P4HA2) expression is a predictor of poor outcome in breast ductal carcinoma in situ (DCIS)

Background

Extracellular matrix (ECM) plays a crucial role in tumour behaviour. Prolyl-4-hydroxlase-A2 (P4HA2) is a key enzyme in ECM remodelling. This study aims to evaluate the prognostic significance of P4HA2 in breast ductal carcinoma in situ (DCIS).

Methods

P4HA2 expression was assessed immunohistochemically in malignant cells and surrounding stroma of a large DCIS cohort comprising 481 pure DCIS and 196 mixed DCIS and invasive carcinomas. Outcome analysis was evaluated using local recurrence free interval (LRFI).

Results

High P4HA2 expression was detected in malignant cells of half of pure DCIS whereas its expression in stroma was seen in 25% of cases. Higher P4HA2 expression was observed in mixed DCIS cases compared to pure DCIS both in tumour cells and in stroma. High P4HA2 was associated with features of high risk DCIS including younger age, higher grade, comedo necrosis, triple negative and HER2-positive phenotypes. Interaction between P4HA2 and radiotherapy was also observed regarding the outcome. High P4HA2 expression was an independent prognostic factor in predicting shorter LRFI.

Conclusion

P4HA2 plays a role in DCIS progression and can potentially be used to predict DCIS outcome. Incorporation of P4HA2 with other clinicopathological parameters could refine DCIS risk stratification that can potentially guide management decisions.

Adjuvant radiotherapy versus observation following lumpectomy in ductal carcinoma in-situ: A meta-analysis of randomized controlled trials

The role of adjuvant radiotherapy (RT) following lumpectomy for ductal carcinoma in-situ (DCIS) was addressed in four major randomized controlled trials (RCTs) which were conducted two to three decades ago. Initial results of these trials suggested the protective role of RT in reducing the ipsilateral breast recurrences. Long-term results of all these four trials, based on more than 10-years follow-up data, have recently been published. A meta-analysis of four published RCTs which have addressed the role of adjuvant RT following lumpectomy for DCIS was conducted. Review manager (Cochrane Collaboration's software) version RevMan 5.2 was used for analysis. Evaluated events were ipsilateral breast recurrences (both DCIS and invasive), regional recurrences, contralateral breast events, distant recurrences, and overall mortality. The events were entered as dichotomous variable. The present meta-analysis included four RCTs and a total of 3680 patients - 1710 received adjuvant RT following lumpectomy while 1970 patients did not receive any adjuvant treatment. Patients who received RT had almost half of risk of ipsilateral breast recurrence (RR = 0.53, 95% CI = 0.45-0.62) and regional recurrence (RR = 0.54, 95% CI = 0.32-0.91) compared to those who did not receive adjuvant treatment - there was absolute risk reduction in 15% (95% CI = 12%-17%) for ipsilateral breast recurrences in adjuvant RT treated patients. There was no significant difference in distant recurrence (RR = 1.06, 95% CI = 0.74-1.53), contralateral breast events (RR = 1.22, 95% CI = 0.98-1.52) and overall mortality (RR = 0.93, 95% CI = 0.79-1.09). Though addition of postoperative RT to lumpectomy does not reduce overall mortality, the present meta-analysis confirms that it decreases the ipsilateral breast and regional recurrence by almost half.

Clinicopathological Risk Factors for an Invasive Breast Cancer Recurrence after Ductal Carcinoma In Situ-A Nested Case-Control Study

Purpose: Ductal carcinoma in situ (DCIS) is treated to prevent progression to invasive breast cancer. Yet, most lesions will never progress, implying that overtreatment exists. Therefore, we aimed to identify factors distinguishing harmless from potentially hazardous DCIS using a nested case-control study.Experimental Design: We conducted a case-control study nested in a population-based cohort of patients with DCIS treated with breast-conserving surgery (BCS) alone (N = 2,658) between 1989 and 2005. We compared clinical, pathologic, and IHC DCIS characteristics of 200 women who subsequently developed ipsilateral invasive breast cancer (iIBC; cases) and 474 women who did not (controls), in a matched setting. Median follow-up time was 12.0 years (interquartile range, 9.0-15.3). Conditional logistic regression models were used to assess associations of various factors with subsequent iIBC risk after primary DCIS.Results: High COX-2 protein expression showed the strongest association with subsequent iIBC [OR = 2.97; 95% confidence interval (95% CI), 1.72-5.10]. In addition, HER2 overexpression (OR = 1.56; 95% CI, 1.05-2.31) and presence of periductal fibrosis (OR = 1.44; 95% CI, 1.01-2.06) were associated with subsequent iIBC risk. Patients with HER2⁺/COX-2^high DCIS had a 4-fold higher risk of subsequent iIBC (vs. HER2^-/COX-2^low DCIS), and an estimated 22.8% cumulative risk of developing subsequent iIBC at 15 years.Conclusions: With this unbiased study design and representative group of patients with DCIS treated by BCS alone, COX-2, HER2, and periductal fibrosis were revealed as promising markers predicting progression of DCIS into iIBC. Validation will be done in independent datasets. Ultimately, this will aid individual risk stratification of women with primary DCIS. Clin Cancer Res; 24(15); 3593-601. ©2018 AACR.

Risk of death from breast cancer after treatment for ductal carcinoma in situ

Background

Studies to date have failed to demonstrate any survival benefit from preventing local recurrence after treatment for ductal breast carcinoma in situ (DCIS). Patient- and tumour-related risk factors for death from breast cancer in women with a primary DCIS were analysed here in a large case–control study.

Methods

A nested case–control study was conducted in a population-based cohort of women with primary DCIS between 1992 and 2012. Women who later died from breast cancer were identified. Four controls per case were selected randomly by incidence density sampling. Medical records and pathology reports were retrieved. Conditional logistic regression was used to calculate odds ratios (ORs) and 95 per cent confidence intervals for risk of death from breast cancer.

Results

From a cohort of 6964 women, 96 who died from breast cancer were identified and these were compared with a group of 318 controls. Tumour size over 25 mm or multifocal DCIS (OR 2·55, 95 per cent c.i. 1·53 to 4·25), a positive or uncertain margin status (OR 3·91, 1·59 to 9·61) and detection outside the screening programme (OR 2·12, 1·16 to 3·86) increased the risk of death from breast cancer. The risks were not affected by age or type of treatment. In the multivariable analysis, tumour size (OR 1·95, 1·06 to 3·67) and margin status (OR 2·69, 1·15 to 7·11) remained significant.

Conclusion

In the present study, large tumour size and positive or uncertain margin status were associated with a higher risk of death from breast cancer after treatment for primary DCIS. More extensive treatment was not associated with lower risk, which may be due to confounding by indication, or indicate that some DCIS has an inherent potential for metastatic spread.

Contralateral Breast Cancer Risk in Women with Ductal Carcinoma In Situ: Is it High Enough to Justify Bilateral Mastectomy?

BACKGROUND

Women with ductal carcinoma in situ (DCIS) are increasingly choosing bilateral mastectomy. We sought to quantify rates of contralateral breast cancer (CBC) and ipsilateral breast tumor recurrence (IBTR) after breast-conserving surgery (BCS) for DCIS, and to compare risk factors for CBC and IBTR.

METHODS

From 1978 to 2011, DCIS patients undergoing BCS with a contralateral breast at risk were identified from a prospectively maintained database. The association of clinicopathologic and treatment factors with CBC and IBTR were evaluated using Kaplan-Meier analysis, multivariable Cox regression, and competing risk regression (CRR).

RESULTS

Of 2759 patients identified, 151 developed CBC and 344 developed IBTR. Five- and 10-year Kaplan-Meier CBC rates were 3.2 and 6.4%. Overall, 10-year IBTR rates were 2.5-fold higher than CBC rates, and, without radiation, 4-fold higher. On CRR, 5- and 10-year rates were 2.9 and 5.8% for CBC, and 7.8 and 14.5% for IBTR. CBC risk and invasive CBC risk were not significantly associated with age, family history, presentation, nuclear grade, year of surgery, or radiation. By multivariable Cox regression, endocrine therapy was associated with lower CBC risk (hazard ratio 0.57, p = 0.03). Ten-year risk of subsequent CBC in the subset of patients who developed IBTR was similar to the cohort as a whole (8.1 vs. 6.4%).

CONCLUSIONS

CBC rates were low across all groups, including those who experienced IBTR. CBC was not associated with factors that increase IBTR risk. While factors associated with IBTR risk are important in decision making regarding management of the index DCIS, they are not an indication for contralateral prophylactic mastectomy.

Updates in the treatment of ductal carcinoma in situ of the breast

PURPOSE OF REVIEW

Ductal carcinoma in situ (DCIS) accounts for approximately 20% of mammographically diagnosed breast cancers. Currently, there is a trend to consider DCIS as a lesion for which treatment deescalation is advocated to avoid overtreatment, that is, radiotherapy in addition to breast-conserving surgery or even surgery at all.

RECENT FINDINGS

The long-term follow-up updates of the four first-generation randomized trials comparing lumpectomy with and without radiation therapy have confirmed that radiation halves the local failure rates. However, radiotherapy is not associated with a survival benefit just as affirmed by the recently published evaluation of the Surveillance, Epidemiology, and End Results registries database, including 108,196 women with DCIS. Nevertheless, the risk of dying of breast cancer increases about factor 18 after experience of an invasive local recurrence. That means at least some DCIS have the potential to progress to a life threatening disease. At the same time, none of the recently updated prospective trials that tested the outcome after excision alone in low-risk DCIS achieved a 10-year local failure rate below 10%.

SUMMARY

DCIS is not a uniform disease. Its clinical behaviour is heterogeneous, but up to date no citeria are available that allow a precise identification of patients with low or very low progression risk who do not need irradiation. Therefore, excision followed by radiotherapy is still the standard of care in patients undergoing breast conservation. Promising new approaches for risk estimation have to be validated prospectively before their use in daily practice can be recommended.

Co-expression of p16 and p53 characterizes aggressive subtypes of ductal intraepithelial neoplasia

In the USA alone, approximately 61,000 new diagnoses of ductal intraepithelial neoplasia 1c-3 (DIN) are made each year. Around 10-20 % of the patients develop a recurrence, about 50 % of which are invasive. Prior studies have shown that invasive breast carcinomas positive for p16 or p53 have a higher frequency of recurrence and a more aggressive course; however, the co-expression of these markers across the entire spectrum of DIN and its potential correlation with grade of the lesions has not been studied previously. Immunohistochemical staining for p16 and p53 was evaluated on 262 DIN lesions from 211 cases diagnosed between 1991 and 2008. The lesions ranged from DIN1b (atypical intraductal hyperplasia) to DIN3 (DCIS, grade 3) and included 45 cases with associated invasive carcinoma. Frequency of staining for both p16 and p53 increased with increasing grade of DIN. Strong co-expression was found exclusively in higher grade DIN lesions (DIN2 and DIN3) particularly those associated with periductal stromal fibrosis and lymphocytic infiltrate. Strong co-expression was seen in 8 of 12 DIN3 lesions (67 %) associated with invasive carcinoma. In conclusion, co-expression of p16 and p53 increases with advancing grade of DIN and is maximal in high grade DIN lesions associated with invasive carcinoma, indicating a more aggressive phenotype. A distinctive variant of DIN with periductal fibrosis and lymphocytic infiltrate invariably falls into the high-grade category, based on either morphology or marker expression. Co-expression of p16/p53 may be of help in distinguishing between high-grade and low-grade DIN lesions.

Predictors for local invasive recurrence of ductal carcinoma in situ of the breast: a meta-analysis

The introduction of mammographic screening has considerably increased the detection rate of ductal carcinoma in situ (DCIS), which has a high probability of recurrence. We carried out a meta-analysis to evaluate the predictive factors including biomarkers, tumor characteristics, and modes of detection on the risk of local invasive recurrence (LIR) following DCIS. Searches were performed in PubMed and EMBASE up to 8 July 2014. Risk estimates (hazard ratios, odds ratios, and relative risks) and their 95% confidence intervals (CIs) were extracted to calculate the strength of the associations between predictive factors and the risk of LIR after treatment of DCIS. STATA 12.0 was used to combine results in this meta-analysis. A total of 18 articles were included in the analysis. Pooled risk estimates and 95% CIs were 1.36 (1.04-1.69) for the positive margin, 1.38 (1.12-1.63) for the nonscreening detection method, 1.04 (0.84-1.24) for high nuclear grade 1, 1.32 (0.98-1.66) for intermediate nuclear grade 2, 1.18 (0.98-1.37) for comedonecrosis, 1.00 (0.92-1.08) for large tumor size, 1.34 (0.82-1.87) for multifocality, 0.74 (0.36-1.12) for estrogen receptor-positive tumors, 0.89 (0.47-1.31) for progesterone receptor-positive tumors, and 1.25 (0.7-1.81) for HER2/neu-positive tumors. Positive margin and non-screening-detected cancers were associated with a higher risk of LIR following DCIS. These predictive factors, after further validation, could be considered to tailor treatment for individual patients.

Relationship Between Margin Width and Recurrence of Ductal Carcinoma In Situ: Analysis of 2996 Women Treated With Breast-conserving Surgery for 30 Years

OBJECTIVE

Our goal was to investigate, in a large population of women with ductal carcinoma in situ (DCIS) and long follow-up, the relationship between margin width and recurrence, controlling for other characteristics.

BACKGROUND

Although DCIS has minimal mortality, recurrence rates after breast-conserving surgery are significant, and half are invasive. Positive margins are associated with increased risk of local recurrence, but there is no consensus regarding optimal negative margin width.

METHODS

We retrospectively reviewed a prospective database of DCIS patients undergoing breast-conserving surgery from 1978 to 2010. Univariate and Cox proportional hazard models were used to investigate the association between margin width and recurrence.

RESULTS

In this review, 2996 cases were identified, of which 363 recurred. Median follow-up for women without recurrence was 75 months (range 0-30 years); 732 were studied for ≥10 years. Controlling for age, family history, presentation, nuclear grade, number of excisions, radiotherapy (RT), endocrine therapy, and year of surgery, margin width was significantly associated with recurrence in the entire population. Larger negative margins were associated with a lower hazard ratio compared with positive margins. An interaction between RT and margin width was significant (P < 0.03); the association of recurrence with margin width was significant in those without RT (P < 0.0001), but not in those with RT (P = 0.95).

CONCLUSIONS

In women not receiving RT, wider margins are significantly associated with a lower rate of recurrence. Obtaining wider negative margins may be important in reducing the risk of recurrence in women who choose not to undergo RT and may not be necessary in those who receive RT.

The prognostic role of HER2 expression in ductal breast carcinoma in situ (DCIS); a population-based cohort study

Background

HER2 is a well-established prognostic and predictive factor in invasive breast cancer. The role of HER2 in ductal breast carcinoma in situ (DCIS) is debated and recent data have suggested that HER2 is mainly related to in situ recurrences. Our aim was to study HER2 as a prognostic factor in a large population based cohort of DCIS with long-term follow-up.

Methods

All 458 patients diagnosed with a primary DCIS 1986–2004 in two Swedish counties were included. Silver-enhanced in situ hybridisation (SISH) was used for detection of HER2 gene amplification and protein expression was assessed by immunohistochemistry (IHC) in tissue microarrays. HER2 positivity was defined as amplified HER2 gene and/or HER2 3+ by IHC. HER2 status in relation to new ipsilateral events (IBE) and Invasive Breast Cancer Recurrences, local or distant (IBCR) was assessed by Kaplan-Meier survival analyses and Cox proportional hazards regression models.

Results

Primary DCIS was screening-detected in 75.5 % of cases. Breast conserving surgery (BCS) was performed in 78.6 % of whom 44.0 % received postoperative radiotherapy. No patients received adjuvant endocrine- or chemotherapy. The majority of DCIS could be HER2 classified (N = 420 (91.7 %)); 132 HER2 positive (31 %) and 288 HER2 negative (69 %)). HER2 positivity was related to large tumor size (P = 0.002), high grade (P < 0.001) and ER- and PR negativity (P < 0.001 for both). During follow-up (mean 184 months), 106 IBCRs and 105 IBEs were identified among all 458 cases corresponding to 54 in situ and 51 invasive recurrences. Eighteen women died from breast cancer and another 114 had died from other causes. The risk of IBCR was statistically significantly lower subsequent to a HER2 positive DCIS compared to a HER2 negative DCIS, (Log-Rank P = 0.03, (HR) 0.60 (95 % CI 0.38–0.94)). Remarkably, the curves did not separate until after 10 years. In ER-stratified analyses, HER2 positive DCIS was associated with lower risk of IBCR among women with ER negative DCIS (Log-Rank P = 0.003), but not for women with ER positive DCIS.

Conclusions

Improved prognostic tools for DCIS patients are warranted to tailor adjuvant therapy. Here, we demonstrate that HER2 positive disease in the primary DCIS is associated with lower risk of recurrent invasive breast cancer.

Local relapse after breast-conserving therapy for ductal carcinoma in situ: a European single-center experience and external validation of the Memorial Sloan-Kettering Cancer Center DCIS nomogram

PURPOSE

Adjuvant treatments after breast-conserving surgery (BCS) for ductal carcinoma in situ to prevent local relapse are considered standard of care. However, patient selection to prevent increased morbidity without proven survival benefit remains a challenge. To predict the risk of ipsilateral breast tumor relapse (IBTR) after BCS, the Memorial Sloan-Kettering Cancer Center (MSKCC) developed a nomogram. The aim of this study was to develop our own prediction model for IBTR and to provide an external validation of the MSKCC nomogram.

METHODS

From 1973 to 2010, 467 patients were treated with BCS for ductal carcinoma in situ at the University Hospital Leuven. Clinicopathologic and treatment parameters of all patients were used to create a multivariable model. The predictive value of the model was evaluated using the concordance index (C-index) and concordance probability estimate (CPE). Multiple imputation was used to account for missing data to allow the MSKCC model to be tested on 467 patients.

RESULTS

Median follow-up was 7.2 years, with 48 women who developed an IBTR. Omission of adjuvant endocrine therapy, younger age, and positive or close surgical margins were significantly associated with an increased risk of IBTR. The bootstrap-corrected C-index for 10-year prediction by our own model was 0.63 and the CPE was 0.61. The C-index and CPE for the 10-year relapse probabilities predicted by the MSKCC nomogram were 0.66 and 0.61, respectively.

CONCLUSIONS

Despite the small number of events, the need for multiple imputation, and few patients without radiation, the MSKCC nomogram performance was somewhat better than our model. This shows that the MSKCC nomogram is externally valid. The MSKCC nomogram allows users to integrate the information from 10 different variables to provide a more precise risk stratification than the use of conventional single variables or hazard ratios.

Predictors of Recurrence in Patients Diagnosed with Ductal Carcinoma In Situ

Although patients diagnosed with ductal carcinoma in situ (DCIS) enjoy a favorable prognosis, recurrence after definitive management does occur in a subset of these patients. Factors influencing the development of recurrence remain poorly understood. A retrospective chart review of 205 consecutive patients who presented to an academic breast center with DCIS from 2000 to 2003 was conducted under an Institutional Review Board-approved protocol. With a median follow-up of 8.5 years, 14 (6.8%) of the 205 patients who presented with DCIS between 2000 and 2003 had a recurrence of their DCIS. The median age of all patients at the time of diagnosis of their initial DCIS was 55.5 years (range, 35.8 to 88.9 years). Patients who experienced tumor recurrence were more likely to have Grade 3 DCIS on initial diagnosis compared with patients without recurrence (72.7 vs 35.4%, P = 0.032). The odds ratio of tumor recurrence for high-grade compared with low-grade DCIS was 4.39. Patient age, race, tumor size, tumor histologic subtype, or histopathologic features was not associated with recurrence. Patients with high-grade DCIS are more likely to recur than patients with low-grade DCIS, and this seems to be more predictive of recurrence than other clinicopathologic markers.

Web based pathology assessment in RTOG 98-04

Aims

Radiation Therapy Oncology Group 98-04 sought to identify women with ‘good risk’ ductal carcinoma in situ (DCIS) who receive no significant benefit from radiation. Enrolment criteria excluded close or positive margins and grade 3 disease. To ensure reproducibility in identifying good risk pathology, an optional web based teaching tool was developed and a random sampling of 10% of submitted slides were reviewed by a central pathologist.

Methods

Submitting pathologists were asked to use the web based teaching tool and submit an assessment of the tool along with the pathology specimen form and DCIS H&E stained slide. Per protocol pathology was centrally reviewed for 10% of the cases.

Results

Of the 55 DCIS cases reviewed, three had close or positive margins and three were assessed to include grade 3 DCIS, therefore 95% of DCIS cases reviewed were correctly graded, and 89% reviewed were pathologically appropriate for enrolment. Regarding the teaching tool, 13% of DCIS cases included forms that indicated the website was used. One of these seven who used the website submitted DCIS of grade 3.

Conclusions

Central review demonstrates high pathological concordance with enrolment eligibility, particularly with regard to accurate grading. The teaching tool appeared to be underused.

Effect of Radiotherapy After Breast-Conserving Surgery for Ductal Carcinoma in Situ: 20 Years Follow-Up in the Randomized SweDCIS Trial

Purpose

Four randomized studies show that adjuvant radiotherapy (RT) lowers the risk of subsequent ipsilateral breast events (IBEs) after breast-conserving surgery (BCS) for ductal carcinoma in situ (DCIS) by approximately 50% after 10 to 15 years. We present 20 years of follow-up data for the SweDCIS trial.

Patients and Methods

Between 1987 and 1999 1,046 women were randomly assigned to RT or not after BCS for primary DCIS. Results up to 2005 have been published, and we now add another 7 years of follow-up. All breast cancer events and causes of death were registered.

Results

There were 129 in situ and 129 invasive IBEs. Absolute risk reduction in the RT arm was 12.0% at 20 years (95% CI, 6.5 to 17.7), with a relative risk reduction of 37.5%. Absolute reduction was 10.0% (95% CI, 6.0 to 14.0) for in situ and 2.0% (95% CI, −3.0 to 7.0) for invasive IBEs. There was a nonstatistically significantly increased number of contralateral events in the RT arm (67 v 48 events; hazard ratio, 1.38; 95% CI, 0.95 to 2.00). Breast cancer–specific death and overall survival were not influenced. Younger women experienced a relatively higher risk of invasive IBE and lower effect of RT. The hazard over time looked different for in situ and invasive IBEs.

Conclusion

Use of adjuvant RT is supported by 20-year follow-up. Modest protection against invasive recurrences and a possible increase in contralateral cancers still call for a need to find groups of patients for whom RT could be avoided or mastectomy with breast reconstruction is indicated.

Narrowing down the focus: what are the main predictive markers for ductal carcinoma in situ?

SUMMARY 

Ductal carcinoma in situ accounts for approximately a quarter of newly diagnosed breast cancer nowadays. It is not life threatening per se, but confers an increased risk for subsequent invasive cancers. Optimal management should be based on the tumor characteristics and tailored to the risk of subsequent recurrence and invasive events. Prediction for recurrence risk has been determined mainly with clinical and histopathologic factors. However, they are imperfect, probably owing to the lack of standardized methods for assessment. Ongoing efforts have been shifted to the use of molecular factors, as well as prediction of noninvasive and invasive recurrences separately. These molecular factors seem to be more powerful in predicting invasive and noninvasive recurrence. However, their emerging roles still need to be validated.

The target for statins, HMG-CoA reductase, is expressed in ductal carcinoma-in situ and may predict patient response to radiotherapy

BACKGROUND

Patients with ductal carcinoma-in-situ (DCIS) are currently not prescribed adjuvant systemic treatment after surgery and radiotherapy. Prediction of DCIS patients who would benefit from radiotherapy is warranted. Statins have been suggested to exert radio-sensitizing effects. The target for cholesterol-lowering statins is HMG-CoA reductase (HMGCR), the rate-limiting enzyme in the mevalonate pathway. The aim of this study was to examine HMGCR expression in DCIS and study its treatment predictive value.

METHODS

A population-based cohort including 458 women diagnosed with primary DCIS between 1986 and 2004 were followed until November 2011 to study long-term survival. Tumor tissue microarrays were constructed, and immunohistochemical analyses were performed to detect cytoplasmic protein expression of HMGCR. The association between DCIS HMGCR expression and invasive breast cancer recurrence-free survival (RFSinv) and overall survival (OS) was analyzed by Kaplan-Meier curves, log rank test, and Cox proportional hazard analysis.

RESULTS

HMGCR was strongly expressed in 24 % of the assessed DCIS samples, moderately expressed in 46 %, and weakly expressed in 23 %; no expression was detected in 7 % of the samples. During the follow-up time (median 13.8 years), 61 patients were diagnosed with an invasive breast cancer recurrence, and 80 patients died. A crude analysis showed no survival benefit from radiotherapy. However, patients with strong HMGCR expression showed an improved RFSinv (log rank, p = 0.03) and OS (log rank, p = 0.04) after radiotherapy. No statistically significant interaction was observed for HMGCR and radiotherapy (RFSinv p = 0.69 and OS p = 0.29).

CONCLUSIONS

This study demonstrates HMGCR expression in DCIS and suggests HMGCR as a predictive marker of response to postoperative radiotherapy in DCIS, although the test for interaction was nonsignificant. Future DCIS studies addressing the potential of statin treatment targeting HMGCR are warranted.

A Comparison of Tumor Biology in Primary Ductal Carcinoma In Situ Recurring as Invasive Carcinoma versus a New In Situ

Introduction. About half of all new ipsilateral events after a primary ductal carcinoma in situ (DCIS) are invasive carcinoma. We studied tumor markers in the primary DCIS in relation to type of event (invasive versus in situ). Methods. Two hundred and sixty-six women with a primary DCIS from two source populations, all with a known ipsilateral event, were included. All new events were regarded as recurrences. Patient and primary tumor characteristics (estrogen receptor (ER), progesterone receptor (PR), HER2, EGFR, and Ki67) were evaluated. Logistic regression was used to calculate odd ratios and 95% confidence intervals in univariate and multivariate analyses. Results. One hundred and thirty-six of the recurrences were invasive carcinoma and 130 were in situ. The recurrence was more often invasive if the primary DCIS was ER+ (OR 2.5, 95% CI 1.2–5.1). Primary DCIS being HER2+ (OR 0.5, 95% CI 0.3–0.9), EGFR+ (OR 0.4, 95% CI 0.2–0.9), and ER95−/HER2+ (OR 0.2, 95% CI 0.1–0.6) had a lower risk of a recurrence being invasive. Conclusions. In this study, comparing type of recurrence after a DCIS showed that the ER−/HER2+ tumors were related to a recurrence being a new DCIS. And surprisingly, tumors being ER+, HER2−, and EGFR− were related to a recurrence being invasive cancer.

Clonal alteration of breast cancer receptors between primary ductal carcinoma in situ (DCIS) and corresponding local events

BACKGROUND

Emerging data propose biomarker alteration due to clonal selection between the primary invasive breast cancer and corresponding metastases. In addition, impact on survival has been demonstrated. The present study investigates the relationship between the oestrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor 2 (HER2) between primary ductal carcinoma in situ (DCIS) and intra-individually matched ipsilateral event.

MATERIALS AND METHODS

The cohort includes 1504 patients, diagnosed with a primary DCIS between 1986 and 2004. Of the 274 patients who developed a local relapse, 135 developed a new in situ carcinoma and 139 an invasive cancer up to 31st December 2011. ER and PR were identified by immunohistochemistry (IHC) and HER2 by silver-enhanced in situ hybridisation (SISH) as well as IHC.

RESULTS

ER (n=112), PR (n=113) and HER2 (n=114) status from both the primary DCIS and the corresponding relapse were assessed and were demonstrated to be discordant in 15.1%, 29.2% and 10.5% respectively. The receptor conversion was both from negative to positive and from positive to negative with no general pattern being seen in spite of sub-dividing into in situ relapse and invasive relapse. However, primary DCIS was HER2 positive in 40.3% whereas in situ and invasive relapses were HER2 positive in 42.9% and 34.5% respectively.

CONCLUSIONS

Receptor conversion for ER, PR and HER2 status occurred between primary DCIS and corresponding local relapse in 10-30%. This study could not confirm that HER2 overexpression in primary DCIS had any impact on tumour progression to invasive cancer which has been proposed.

Post-operative radiotherapy for ductal carcinoma in situ of the breast

BACKGROUND

The addition of radiotherapy (RT) following breast conserving surgery (BCS) was first shown to reduce the risk of ipsilateral recurrence in the treatment of invasive breast cancer. Ductal carcinoma in situ (DCIS) is a pre-invasive lesion. Recurrence of ipsilateral disease following BCS can be either DCIS or invasive breast cancer. Randomised controlled trials (RCTs) have shown that RT can reduce the risk of recurrence, but assessment of potential long-term complications from addition of RT following BSC for DCIS has not been reported for women participating in RCTs.

OBJECTIVES

To summarise the data from RCTs testing the addition of RT to BCS for treatment of DCIS to determine the balance between the benefits and harms.

SEARCH METHODS

We searched the Cochrane Breast Cancer Group Specialised Register (2 June 2011), Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2008, Issue 1), MEDLINE (2 June 2011), EMBASE (2 June 2011) and the World Health Organization's International Clinical Trials Registry Platform (WHO ICTRP; 2 June 2011). Reference lists of articles and handsearching of ASCO (2007), ESMO (2002 to 2007), and St Gallen (2005 to 2007) conferences were performed.

SELECTION CRITERIA

RCTs of breast conserving surgery with and without radiotherapy in women at first diagnosis of pure ductal carcinoma in situ (no invasive disease present).

DATA COLLECTION AND ANALYSIS

Two authors independently assessed each potentially eligible trial for inclusion and its quality. Two authors also independently extracted data from published Kaplan-Meier analysis (survival curves) and reported summary statistics. Data were extracted and pooled for four trials. Data for planned subgroups were extracted and pooled for analysis.There were insufficient data to pool for long-term toxicity from radiotherapy.

MAIN RESULTS

Four RCTs involving 3925 women were identified and included in this review. All were high quality with minimal risk of bias. Three trials compared the addition of RT to BCS. One trial was a two by two factorial design comparing the use of RT and tamoxifen, each separately or together, in which participants were randomised in at least one arm. Analysis confirmed a statistically significant benefit from the addition of radiotherapy on all ipsilateral breast events (hazards ratio (HR) 0.49; 95% CI 0.41 to 0.58, P < 0.00001), ipsilateral invasive recurrence (HR 0.50; 95% CI 0.32 to 0.76, p=0.001) and ipsilateral DCIS recurrence (HR 0.61; 95% CI 0.39 to 0.95, P = 0.03). All the subgroups analysed benefited from addition of radiotherapy. No significant long-term toxicity from radiotherapy was found. No information about short-term toxicity from radiotherapy or quality of life data were reported.

AUTHORS' CONCLUSIONS

This review confirms the benefit of adding radiotherapy to breast conserving surgery for the treatment of all women diagnosed with DCIS. No long-term toxicity from use of radiotherapy was identified.

The consequence of undertreatment of patients treated with breast conserving therapy for ductal carcinoma in-situ

BACKGROUND

The use of clinical features to allocate adjuvant therapy in the treatment of ductal carcinoma in situ with breast-conserving therapy remains controversial.

METHODS

A review of patients with ductal carcinoma in situ treated with breast-conserving therapy was performed. The recurrence rate was examined in relation to patient age, tumor characteristics, Van Nuys Prognostic Index, and the receipt of prescribed adjuvant therapies.

RESULTS

Six percent of patients (17 of 294) had developed local recurrences after a median follow-up period of 63 months. Fifty-nine percent of patients (91 of 154) with estrogen receptor-positive tumors did not receive prescribed tamoxifen. Thirty-one percent of patients (45 of 147) with Van Nuys Prognostic Index scores ≥7 did not receive recommended radiation therapy. Receipt of prescribed adjuvant therapy did not result in a decrease in the rate of local recurrence. Patient age was the only factor associated with local recurrence on univariate but not on multivariate analysis (P = .374).

CONCLUSIONS

A low rate of local recurrence was achieved despite a large number of patients' not receiving prescribed adjuvant therapies.

Mammography casting-type calcification and risk of local recurrence in DCIS: analyses from a randomised study

BACKGROUND

We studied the association between mammographic calcifications and local recurrence in the ipsilateral breast.

METHODS

Case-cohort study within a randomised trial of radiotherapy in breast conservation for ductal cancer in situ of the breast (SweDCIS). We studied mammograms from cases with an ipsilateral breast event (IBE) and from a subcohort randomly sampled at baseline. Lesions were classified as a density without calcifications, architectural distortion, powdery, crushed stone-like or casting-type calcifications.

RESULTS

Calcifications representing necrosis were found predominantly in younger women. Women with crushed stone or casting-type microcalcifications had higher histopathological grade and more extensive disease. The relative risk (RR) of a new IBE comparing those with casting-type calcifications to those without calcifications was 2.10 (95% confidence interval (CI) 0.92-4.80). This risk was confined to in situ recurrences; the RR of an IBE associated with casting-type calcifications on the mammogram adjusted for age and disease extent was 16.4 (95% CI 2.20-140).

CONCLUSION

Mammographic appearance of ductal carcinoma in situ of the breast is prognostic for the risk of an in situ IBE and may also be an indicator of responsiveness to RT in younger women.

Radiation therapy after breast-conserving surgery

SUMMARY Whole-breast irradiation in combination with breast-conserving surgery is a recognized standard alternative to mastectomy for the local treatment of early breast cancer. This article will review the evidence on the relationship of local control in the treated breast and survival, the indications of a boost dose to the tumor bed and the need for breast irradiation in ductal carcinoma in situ. Novel, shorter fractionation schemes allow the constraints of daily treatment courses over several weeks to be reduced, and recent technical improvements in treatment delivery will improve the results of treatment – in terms of local control and reduction of toxicity, and long-term sequelae. Research should focus on identifying molecular markers of radiation sensitivity and designing specific, targeted modulators of the radiation response in breast cancer.

Radiotherapy after conservative surgery in ductal carcinoma in situ of the breast: a review

Several large prospective and retrospective studies have demonstrated excellent long-term outcomes after breast conservative treatment with radiation in invasive breast cancer. Breast-conserving surgery (BCS) followed by radiotherapy (RT) is an accepted management strategy for patients with DCIS. Adding radiation treatment after conservative surgery enables to reduce, without any significant risks, the rate of local recurrence (LR) by approximately 50% in retrospective and randomized clinical trials. As about 50% of LRs are invasive and have a negative psychological impact, minimizing recurrence is important. Local and local-regional recurrences after initial breast conservation treatment with radiation can be salvaged with high rates of survival and freedom from distant metastases.

Clinical outcomes of ductal carcinoma in situ of the breast treated with partial mastectomy without adjuvant radiotherapy

PURPOSE

Some recent trials suggest that postoperative adjuvant radiotherapy (RT) may be safely omitted after breast-conserving surgery (BCS) for some patients with ductal carcinoma in situ (DCIS). In this study, we reviewed clinical outcomes of patients with DCIS treated with partial mastectomy (PM) without adjuvant RT.

MATERIALS AND METHODS

Medical records of 28 patients (29 breasts) with DCIS who were treated with PM, but without RT, between April 1991 and December 2010 were retrospectively analyzed. Based on established criteria (2.0 cm or less in size and no comedonecrosis), 18 patients were treated without RT after PM. Seven patients (8 breasts) who did not receive RT due to refusal were also included in this study. Three other patients were excluded because data concerning comedonecrosis were not available.

RESULTS

For the 25 patients included in this study, the mean age of the 18 patients who met the criteria was 47.9±6.2 years, and 47.6±12.7 years for the 7 patients who did not. The mean sizes of the primary tumors were 0.6±0.4 cm and 0.9±0.3 cm, respectively, in these two groups. Among these 25 patients (26 breasts) treated without RT, we observed no ipsilateral breast tumor recurrence or mortality within a mean follow-up of 84 months.

CONCLUSION

Based on this small number of cases, patients with DCIS, who were selected for tumor size less than 2 cm and absence of comedonecrosis, may be treated successfully with BCS; adjuvant RT may be omitted.

Role of the radiotherapy boost on local control in ductal carcinoma in situ

Ductal carcinoma in situ of the breast is associated with low mortality rates, but local relapse is a matter of concern in this disease. Risk factors for local relapse include young age, close or positive margins, and tumor necrosis. Whole breast irradiation following breast-conserving surgery for ductal carcinoma in situ significantly reduces the risk of local relapse as compared to breast-conserving surgery alone. Studies point to similar outcomes between breast-conserving surgery plus radiotherapy and mastectomy, in the absence of extensive disease. A complementary boost to the surgical bed improves outcomes for patients with invasive breast cancer. However, the effect of this strategy has never been prospectively reported for ductal carcinoma in situ. Two randomized controlled trials assessing this issue are ongoing. This paper represents an update on available literature about radiotherapy for DCIS with a special focus on the role of a radiotherapy boost to the tumor bed.

Evaluation of a breast cancer nomogram for predicting risk of ipsilateral breast tumor recurrences in patients with ductal carcinoma in situ after local excision

PURPOSE

Prediction of patients at highest risk for ipsilateral breast tumor recurrence (IBTR) after local excision of ductal carcinoma in situ (DCIS) remains a clinical concern. The aim of our study was to evaluate a published nomogram from Memorial Sloan-Kettering Cancer Center to predict for risk of IBTR in patients with DCIS from our institution.

PATIENTS AND METHODS

We retrospectively identified 794 patients with a diagnosis of DCIS who had undergone local excision from 1990 through 2007 at the MD Anderson Cancer Center (MDACC). Clinicopathologic factors and the performance of the Memorial Sloan-Kettering Cancer Center nomogram for prediction of IBTR were assessed for 734 patients who had complete data.

RESULTS

There was a marked difference with respect to tumor grade, prevalence of necrosis, initial presentation, final margins, and receipt of endocrine therapy between the two cohorts. The biggest difference was that more patients received radiation in the MDACC cohort (75% at MDACC v 49% at MSKCC; P < .001). Follow-up time in the MDACC cohort was longer than in the MSKCC cohort (median 7.1 years v 5.6 years), and the recurrence rate was lower in the MDACC cohort (7.9% v 11%). The median 5-year probability of recurrence was 5%, and the median 10-year probability of recurrence was 7%. The nomogram for prediction of 5- and 10-year IBTR probabilities demonstrated imperfect calibration and discrimination, with a concordance index of 0.63.

CONCLUSION

Predictive models for IBTR in patients with DCIS who were treated with local excision are imperfect. Our current ability to accurately predict recurrence on the basis of clinical parameters alone is limited.

Tumor characteristics as predictors of local recurrence after treatment of ductal carcinoma in situ: a meta-analysis

While ductal carcinoma in situ (DCIS) is seldom life threatening, the management of DCIS remains a dilemma for patients and their physicians. Aggressive treatment reduces the risk of ipsilateral breast tumor recurrence (IBTR), but has never been proven to improve survival. There is interest in identifying the prognostic factors for determining low-risk DCIS patients, but a comprehensive review of high-quality evidence on tumor characteristics in predicting local recurrence has never been carried out. We examined the following tumor characteristics: biomarkers, comedonecrosis, focality, surgical margin, method of detection, tumor grade, and tumor size. For this systematic review we restricted the analyses to the results of subgroup analyses from randomized controlled trials (RCTs) and multivariate analyses from RCTs and observational studies. We identified 44 eligible articles. The pooled random-effects risk estimates for IBTR are comedonecrosis 1.71(95% CI, 1.36-2.16), focality 1.95(95% CI, 1.59-2.40), margin 2.25(95% CI, 1.77-2.86), method of detection 1.35(95% CI, 1.12-1.62), tumor grade 1.81(95% CI, 1.53-2.13), and tumor size 1.63(95% CI, 1.30-2.06). Limited evidence indicated that women whose DCIS is ER-negative, PR-negative, or HER2/neu receptor positive have an IBTR higher than those whose DCIS is ER-positive, PR-positive, and HER2/neu receptor negative. A variety of tumor characteristics are significant predictors for IBTR. These results are important for both clinicians and patients to interpret the risk of local recurrence and to decide on a course of treatment.

Nomogram for predicting the risk of local recurrence after breast-conserving surgery for ductal carcinoma in situ

PURPOSE

While the mortality associated with ductal carcinoma in situ (DCIS) is minimal, the risk of ipsilateral breast tumor recurrence (IBTR) after breast-conserving surgery (BCS) is relatively high. Radiation therapy (RT) and antiestrogen agents reduce the risk of IBTR and are considered standard treatment options after BCS. However, they have never been proven to improve survival, and in themselves carry rare but serious risks. Individualized estimation of IBTR risk would assist in decision making regarding the various treatment options for women with DCIS.

PATIENTS AND METHODS

From 1991 to 2006, 1,868 consecutive patients treated with BCS for DCIS were identified. A multivariate Cox proportional hazards model was constructed using the 1,681 in whom data were complete. Ten clinical, pathologic, and treatment variables were built into a nomogram estimating probability of IBTR at 5 and 10 years after BCS. The model was validated for discrimination and calibration using bootstrap resampling.

RESULTS

The DCIS nomogram for prediction of 5- and 10-year IBTR probabilities demonstrated good calibration and discrimination, with a concordance index of 0.704 (bootstrap corrected, 0.688) and a concordance probability estimate of 0.686. Factors with the greatest influence on risk of IBTR in the model included adjuvant RT or endocrine therapy, age, margin status, number of excisions, and treatment time period.

CONCLUSION

The DCIS nomogram integrates 10 clinicopathologic variables to provide an individualized risk estimate of IBTR in a woman with DCIS treated with BCS. This tool may assist in individual decision making regarding various treatment options and help avoid over- and undertreatment of noninvasive breast cancer.

Ductal carcinoma in situ (DCIS): pathological features, differential diagnosis, prognostic factors and specimen evaluation

Ductal carcinoma in situ (DCIS) is a heterogeneous, unicentric precursor of invasive breast cancer, which is frequently identified through mammographic breast screening programs. The lesion can cause particular difficulties for specimen handling in the laboratory and typically requires even more diligent macroscopic assessment and sampling than invasive disease. Pitfalls and tips for macroscopic handling, microscopic diagnosis and assessment, including determination of prognostic factors, such as cytonuclear grade, presence or absence of necrosis, size of the lesion and distance to margins are described. All should be routinely included in histopathology reports of this disease; in order not to omit these clinically relevant details, synoptic reports, such as that produced by the College of American Pathologists are recommended. No biomarkers have been convincingly shown, and validated, to predict the behavior of DCIS till date.