Management and 5-year outcomes in 9938 women with screen-detected ductal carcinoma in situ: the UK Sloane Project

The clinicopathological features of breast cancer in Peutz-Jeghers syndrome: results from an international survey

BACKGROUND

Female patients with Peutz-Jeghers syndrome (PJS) have an increased risk of breast cancer (BrCa), and surveillance is recommended. However, clinicopathological features of their tumors and prognosis are lacking. To facilitate more precise future guideline development, we evaluated these data.

METHODS

We conducted an international survey for InSiGHT members to collect retrospective data on PJS patients with diagnosed breast cancer.

RESULTS

We received 23 responses, including three centers with data on BrCa patients. All reported BrCa patients were female. In total, the cohort comprised 27 patients with 34 BrCa (five bilateral synchronous, one bilateral metachronous, and one metachronous unilateral tumours). The median age at first cancer diagnosis was 45 years (range 26-67). Most cancers were ductal carcinoma, either invasive (13) or in situ (DCIS; 19). TNM staging for invasive cancer was available in thirteen cases, of which nine were T1N0M0. Among tumors with histological reports, 14/15 were oestrogen receptor positive, 8/15 were progesterone receptor positive, and 4/15 were HER2 positive. There were no triple negative breast cancers. Twenty-five patients had follow-up data, comprising 229 patient years. Eleven patients had died of any cause during follow-up. Survival at 5 years was 73%.

CONCLUSION

Overall, breast cancers that occur in this PJS population seem to have favorable characteristics and prognosis. These data will help inform discussions about risk management in patients with PJS. Further research is needed to better understand lifetime risk, the optimal surveillance modality and its outcomes.

Impact of resection margin width on local recurrence following breast-conserving surgery and whole breast radiotherapy for pure ductal carcinoma in situ: a systematic review and meta-analysis

Objective

The aim of this study was to determine the impact of margin width and boost radiotherapy on the local recurrence risk of pure ductal carcinoma in situ (DCIS).

Methods and analysis

This is a prospectively registered systematic review and meta-analysis reporting relative risk (RR), OR and HR margin width outcomes. Eligible studies included prospective and retrospective case series with defining margin widths and 48 months of minimum follow-up. All patients (100%) received adjuvant whole breast radiotherapy (WBRT).

Results

A total of 40 265 patients with pure DCIS in 31 studies were included. ORs and RR were calculated from 15 studies in 12 519 patients, and HRs were calculated from 12 studies in 12 946 patients. Local recurrence was significantly greater with narrower 'close' margins; 0.1-1 mm versus >1 mm in RR (2.88, 95% CI 1.86 to 3.90; p<0.05), OR (4.82, 95% CI 2.45 to 9.48; p<0.05) and HR analysis (1.34, 95% CI 1.01 to 1.67; p<0.05). Compared with margins >2 mm, significantly greater local recurrence was observed in margins 0.1-2 mm in RR (1.72, 95% CI 1.09 to 2.35; p<0.05) and OR (4.43, 95% CI 3.02 to 6.50; p<0.05). Comparing 0.1-1 mm versus >1 mm and 0.1-2 mm versus >2 mm, differences in local recurrence were not statistically significant, once adjusted for boost radiotherapy.

Conclusions

In pure DCIS with WBRT, the local recurrence risk reduces as margin width increases up to 2 mm. The strength of the recommendation for a minimum clear margin of 2 mm is limited by a lack of data comparing 1.1-2 mm with >2 mm. The association between recurrence and close margins is not significant following boost radiotherapy, suggesting a possible alternative to re-excision in patients with close margins <2 mm.

Systematic review registration

CRD42022308524.

The impact of inter-cycle treatment delays on 5-year all-cause mortality in early-stage breast cancer: A retrospective cohort study

BACKGROUND

Inter-cycle delays to chemotherapy are often required to manage drug toxicity. The impact of delays on mortality is poorly characterised. This retrospective cohort study examined the association of treatment delay with all-cause mortality in early-stage breast cancer.

METHODS

This real-world analytical study included adult women with stage 2 or 3 breast cancer receiving first-line (neo-)adjuvant chemotherapy between 01/01/2014 and 31/12/2015 in England. Inter-cycle delays > 7 days during the treatment period were calculated, and the association of treatment delay with 5-year all-cause mortality was investigated. Survival was compared between patients experiencing treatment delay and those completing treatment to schedule using landmark methodology and Kaplan-Meier (KM) estimator. Cox proportional hazards regression was used to investigate the impact of delay on survival, using inverse probability of treatment weighting to adjust for confounding variables.

RESULTS

8567 patients were included. 17 % (1448) experienced inter-cycle delay > 7 days during the treatment period. 1120 (13 %) women had died at the end of the 5-year follow up period. Median follow-up time was 5.5 years. Survival probability was significantly lower in patients experiencing treatment delay by KM estimator analysis (p < 0.0001). Cox proportional hazards regression demonstrated a significant positive association between delay and 5-year all-cause mortality (HR 1.33 95 % CI 1.12-1.61, p < 0.001).

CONCLUSIONS

This is the largest study of its kind demonstrating an association between treatment delay and all-cause mortality. These findings support interventions to improve toxicity management allowing completion of chemotherapy to schedule where patients experience treatment delay due to treatment-related toxicity or hospital capacity pressures.

Molecular Expression Assays Improve the Prediction of Local and Invasive Local Recurrence After Breast-Conserving Surgery for Ductal Carcinoma In Situ

PURPOSE

Ductal carcinoma in situ (DCIS) is routinely treated with adjuvant radiotherapy (RT) after breast-conserving surgery (BCS). The inability to accurately estimate an individual's risk of local recurrence (LR) and invasive LR using clinicopathologic factors (CPF) contributes to the overtreatment of DCIS. We examined the impact of the 12-gene DCIS Score (DS) and the 21-gene Recurrence Score (RS) on the accuracy of predicting LR and invasive LR.

METHODS

A population-based cohort diagnosed with pure DCIS treated with BCS ± RT from 1994 to 2003 was used. All patients had expert pathology review and assessment of the DS and RS. Predictive models (CPF alone, DS + CPF, and RS + CPF) were developed using multivariable Cox regression analyses to predict 10-year LR and invasive LR risks. Models were evaluated on the basis of c-statistic, -2log likelihood estimate (-2LLE), and Akaike information criterion. Calibration was performed using bootstrap resamples, with replacement.

RESULTS

The cohort includes 1,226 women treated with BCS; 712 received RT. 194 women (15.8%) experienced ipsilateral LR as a first event; 112 were invasive. Models including the DS or RS performed better in predicting the 10-year risk of LR compared with models on the basis of CPF alone with excellent calibration. The two molecular-based models also performed better in predicting invasive LR compared with the CPF model but the model incorporating the RS did not perform better in the prediction of invasive LR compared with the DS-based model.

CONCLUSION

Models incorporating the DS or RS more accurately predicted the 10-year risk of LR and invasive LR after BCS compared with models on the basis of CPF alone. Inclusion of the RS, compared with DS, did not improve the prediction of the 10-year risk of invasive LR.

Invasive recurrence after breast conserving treatment of ductal carcinoma in situ of the breast in the Netherlands: time trends and the association with tumour grade

BACKGROUND

The first aim of this study was to examine trends in the risk of ipsilateral invasive breast cancer (iIBC) after breast-conserving surgery (BCS) of ductal carcinoma in situ (DCIS). A second aim was to analyse the association between DCIS grade and the risk of iIBC following BCS.

PATIENTS AND METHODS

In this population-based, retrospective cohort study, the Netherlands Cancer Registry collected information on 25,719 women with DCIS diagnosed in the period 1989-2021 who underwent BCS. Of these 19,034 received adjuvant radiotherapy (RT). Kaplan-Meier analyses and Cox regression models were used.

RESULTS

A total of 1135 patients experienced iIBC. Ten-year cumulative incidence rates of iIBC for patients diagnosed in the periods 1989-1998, 1999-2008 and 2009-2021 undergoing BCS without RT, were 12.6%, 9.0% and 5.0% (P < 0.001), respectively. For those undergoing BCS with RT these figures were 5.7%, 3.7% and 2.2%, respectively (P < 0.001). In the multivariable analyses, DCIS grade was not associated with the risk of iIBC.

CONCLUSION

Since 1989 the risk of iIBC has decreased substantially and has become even lower than the risk of invasive contralateral breast cancer. No significant association of DCIS grade with iIBC was found, stressing the need for more powerful prognostic factors to guide the treatment of DCIS.

Disease-specific survival outcomes for patients after locoregional treatment for ductal carcinoma in situ: observational cohort study

BACKGROUND

Breast-conserving surgery alone, breast-conserving surgery with adjuvant radiation treatment, and mastectomy are guideline-concordant treatments for ductal carcinoma in situ. The aim of this study was to compare survival outcomes between these treatment options.

METHODS

A stratified random sample of patients diagnosed with pure ductal carcinoma in situ between 2008 and 2014 was selected from 1330 sites in the USA. Data on diagnosis, treatment, and follow-up were abstracted by local cancer registrars. Population-averaged marginal estimates of disease-specific survival and overall survival for breast-conserving surgery alone, breast-conserving surgery with radiation treatment, and mastectomy were obtained by combining sampling and overlap weights.

RESULTS

A total of 18 442 women were included, with a median follow-up of 67.8 (interquartile range 46.1-93.5) months. A total of 35 women died from breast cancer, at a median age of 62 (interquartile range 50-74) years. Population-averaged 8-year rates of disease-specific survival were 99.6% or higher for all treatment groups, with no significant differences between groups (breast-conserving surgery alone versus breast-conserving surgery with radiation treatment, HR 1.19 (95% c.i. 0.29 to 4.85); and mastectomy versus breast-conserving surgery with radiation treatment, HR 1.74 (95% c.i. 0.53 to 5.72). There was no difference in overall survival between the patients who underwent a mastectomy and the patients who underwent breast-conserving surgery with radiation treatment (HR 1.09 (95% c.i. 0.83 to 1.43)). Patients who underwent breast-conserving surgery alone had lower overall survival compared with the patients who underwent breast-conserving surgery with radiation treatment (HR 1.29 (95% c.i. 1.00 to 1.67)). This survival difference vanished for all but one subgroup, namely patients less than 65 years (HR 1.86 (95% c.i. 1.15 to 3.00)).

CONCLUSION

There was no statistically significant difference in disease-specific survival between women operated with breast-conserving surgery alone, breast-conserving surgery with radiation treatment, or mastectomy for ductal carcinoma in situ. Given the low absolute risk of disease-specific mortality, these results provide confidence in offering individualized locoregional treatment without fear of compromising survival.

Ductal carcinoma in situ develops within clonal fields of mutant cells in morphologically normal ducts

Mutations are abundantly present in tissues of healthy individuals, including the breast epithelium. Yet it remains unknown whether mutant cells directly induce lesion formation or first spread, leading to a field of mutant cells that is predisposed towards lesion formation. To study the clonal and spatial relationships between morphologically normal breast epithelium adjacent to pre-cancerous lesions, we developed a three-dimensional (3D) imaging pipeline combined with spatially resolved genomics on archival, formalin-fixed breast tissue with the non-obligate breast cancer precursor ductal carcinoma in situ (DCIS). Using this 3D image-guided characterization method, we built high-resolution spatial maps of DNA copy number aberration (CNA) profiles within the DCIS lesion and the surrounding normal mammary ducts. We show that the local heterogeneity within a DCIS lesion is limited. However, by mapping the CNA profiles back onto the 3D reconstructed ductal subtree, we find that in eight out of 16 cases the healthy epithelium adjacent to the DCIS lesions has overlapping structural variations with the CNA profile of the DCIS. Together, our study indicates that pre-malignant breast transformations frequently develop within mutant clonal fields of morphologically normal-looking ducts. © 2024 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

Application of deep learning on mammographies to discriminate between low and high-risk DCIS for patient participation in active surveillance trials

BACKGROUND

Ductal Carcinoma In Situ (DCIS) can progress to invasive breast cancer, but most DCIS lesions never will. Therefore, four clinical trials (COMET, LORIS, LORETTA, AND LORD) test whether active surveillance for women with low-risk Ductal carcinoma In Situ is safe (E. S. Hwang et al., BMJ Open, 9: e026797, 2019, A. Francis et al., Eur J Cancer. 51: 2296-2303, 2015, Chizuko Kanbayashi et al. The international collaboration of active surveillance trials for low-risk DCIS (LORIS, LORD, COMET, LORETTA),  L. E. Elshof et al., Eur J Cancer, 51, 1497-510, 2015). Low-risk is defined as grade I or II DCIS. Because DCIS grade is a major eligibility criteria in these trials, it would be very helpful to assess DCIS grade on mammography, informed by grade assessed on DCIS histopathology in pre-surgery biopsies, since surgery will not be performed on a significant number of patients participating in these trials.

OBJECTIVE

To assess the performance and clinical utility of a convolutional neural network (CNN) in discriminating high-risk (grade III) DCIS and/or Invasive Breast Cancer (IBC) from low-risk (grade I/II) DCIS based on mammographic features. We explored whether the CNN could be used as a decision support tool, from excluding high-risk patients for active surveillance.

METHODS

In this single centre retrospective study, 464 patients diagnosed with DCIS based on pre-surgery biopsy between 2000 and 2014 were included. The collection of mammography images was partitioned on a patient-level into two subsets, one for training containing 80% of cases (371 cases, 681 images) and 20% (93 cases, 173 images) for testing. A deep learning model based on the U-Net CNN was trained and validated on 681 two-dimensional mammograms. Classification performance was assessed with the Area Under the Curve (AUC) receiver operating characteristic and predictive values on the test set for predicting high risk DCIS-and high-risk DCIS and/ or IBC from low-risk DCIS.

RESULTS

When classifying DCIS as high-risk, the deep learning network achieved a Positive Predictive Value (PPV) of 0.40, Negative Predictive Value (NPV) of 0.91 and an AUC of 0.72 on the test dataset. For distinguishing high-risk and/or upstaged DCIS (occult invasive breast cancer) from low-risk DCIS a PPV of 0.80, a NPV of 0.84 and an AUC of 0.76 were achieved.

CONCLUSION

For both scenarios (DCIS grade I/II vs. III, DCIS grade I/II vs. III and/or IBC) AUCs were high, 0.72 and 0.76, respectively, concluding that our convolutional neural network can discriminate low-grade from high-grade DCIS.

Sonography-based multimodal information platform for identifying the surgical pathology of ductal carcinoma in situ

BACKGROUND

The risk of ductal carcinoma in situ (DCIS) identified by biopsy often increases during surgery. Therefore, confirming the DCIS grade preoperatively is necessary for clinical decision-making.

PURPOSE

To train a three-classification deep learning (DL) model based on ultrasound (US), combining clinical data, mammography (MG), US, and core needle biopsy (CNB) pathology to predict low-grade DCIS, intermediate-to-high-grade DCIS, and upstaged DCIS.

MATERIALS AND METHODS

Data of 733 patients with 754 DCIS cases confirmed by biopsy were retrospectively collected from May 2013 to June 2022 (N1), and other data (N2) were confirmed by biopsy as low-grade DCIS. The lesions were randomly divided into training (n=471), validation (n=142), and test (n = 141) sets to establish the DCIS-Net. Information on the DCIS-Net, clinical (age and sign), US (size, calcifications, type, breast imaging reporting and data system [BI-RADS]), MG (microcalcifications, BI-RADS), and CNB pathology (nuclear grade, architectural features, and immunohistochemistry) were collected. Logistic regression and random forest analyses were conducted to develop Multimodal DCIS-Net to calculate the specificity, sensitivity, accuracy, receiver operating characteristic curve, and area under the curve (AUC).

RESULTS

In the test set of N1, the accuracy and AUC of the multimodal DCIS-Net were 0.752-0.766 and 0.859-0.907 in the three-classification task, respectively. The accuracy and AUC for discriminating DCIS from upstaged DCIS were 0.751-0.780 and 0.829-0.861, respectively. In the test set of N2, the accuracy and AUC of discriminating low-grade DCIS from upstaged low-grade DCIS were 0.769-0.987 and 0.818-0.939, respectively. DL was ranked from one to five in the importance of features in the multimodal-DCIS-Net.

CONCLUSION

By developing the DCIS-Net and integrating it with multimodal information, diagnosing low-grade DCIS, intermediate-to high-grade DCIS, and upstaged DCIS is possible. It can also be used to distinguish DCIS from upstaged DCIS and low-grade DCIS from upstaged low-grade DCIS, which could pave the way for the DCIS clinical workflow.

Atypia detected during breast screening and subsequent development of cancer: observational analysis of the Sloane atypia prospective cohort in England

OBJECTIVE

To explore how the number and type of breast cancers developed after screen detected atypia compare with the anticipated 11.3 cancers detected per 1000 women screened within one three year screening round in the United Kingdom.

DESIGN

Observational analysis of the Sloane atypia prospective cohort in England.

SETTING

Atypia diagnoses through the English NHS breast screening programme reported to the Sloane cohort study. This cohort is linked to the English Cancer Registry and the Mortality and Birth Information System for information on subsequent breast cancer and mortality.

PARTICIPANTS

3238 women diagnosed as having epithelial atypia between 1 April 2003 and 30 June 2018.

MAIN OUTCOME MEASURES

Number and type of invasive breast cancers detected at one, three, and six years after atypia diagnosis by atypia type, age, and year of diagnosis.

RESULTS

There was a fourfold increase in detection of atypia after the introduction of digital mammography between 2010 (n=119) and 2015 (n=502). During 19 088 person years of follow-up after atypia diagnosis (until December 2018), 141 women developed breast cancer. Cumulative incidence of cancer per 1000 women with atypia was 0.95 (95% confidence interval 0.28 to 2.69), 14.2 (10.3 to 19.1), and 45.0 (36.3 to 55.1) at one, three, and six years after atypia diagnosis, respectively. Women with atypia detected more recently have lower rates of subsequent cancers detected within three years (6.0 invasive cancers per 1000 women (95% confidence interval 3.1 to 10.9) in 2013-18 v 24.3 (13.7 to 40.1) in 2003-07, and 24.6 (14.9 to 38.3) in 2008-12). Grade, size, and nodal involvement of subsequent invasive cancers were similar to those of cancers detected in the general screening population, with equal numbers of ipsilateral and contralateral cancers.

CONCLUSIONS

Many atypia could represent risk factors rather than precursors of invasive cancer requiring surgery in the short term. Women with atypia detected more recently have lower rates of subsequent cancers detected, which might be associated with changes to mammography and biopsy techniques identifying forms of atypia that are more likely to represent overdiagnosis. Annual mammography in the short term after atypia diagnosis might not be beneficial. More evidence is needed about longer term risks.

Treatments and Prognosis of the Breast Ductal Carcinoma In Situ

INTRODUCTION

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

PATIENTS AND METHODS

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

RESULTS

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

CONCLUSION

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

Is it Time to Retire the Term of Low-Grade Ductal Carcinoma in Situ and Replace it With Ductal Neoplasia?

As the leading cause of cancer morbidity and the second leading cause of cancer mortality among women, breast cancer continues to remain a major global public health problem. Consequently, significant attention has been directed toward early breast cancer detection and prevention. As a result, the number of image-detected biopsies has increased, and minimally invasive diagnostic procedures have almost replaced open surgical biopsies. Therefore, pathologists are expected to provide more information with less tissue and diagnose increasing numbers of atypical proliferative breast lesions, in situ lesions, and small breast carcinomas. This is a difficult task, as reflected by continuous reports highlighting the challenges associated with morphologic distinction between atypical ductal hyperplasia and low-grade ductal carcinoma in situ. The current interobserver variability among pathologists to accurately define these two entities often leads to silent overdiagnosis and overtreatment. Up to now, there are no reproducible morphologic features and/or any reliable biomarkers that can accurately separate the above-mentioned entities. Despite these reports, patients diagnosed with low-grade ductal carcinoma in situ are subject to cancer therapy regardless of the fact that low-grade ductal carcinoma in situ is known to be an indolent lesion. Studies have shown that low and high-grade ductal carcinoma in situ are genetically different forms of breast cancer precursors; however, the term ductal carcinoma in situ is followed by cancer therapy regardless of the grade and biology of the tumor. In contrast, patients with the diagnoses of atypical ductal hyperplasia do not undergo cancer therapy. In the current article, attempts are made to highlight the continuous dilemma in distinction between atypical ductal hyperplasia and low-grade ductal carcinoma in situ. Going forward, we suggest that low-grade ductal carcinoma in situ be referred to as ductal neoplasia. This alternative terminology allows for different management and follow-up strategies by eliminating the word carcinoma.

Can Molecular Biomarkers Help Reduce the Overtreatment of DCIS?

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

Everybody needs good neighbours: the progressive DCIS microenvironment

Ductal carcinoma in situ (DCIS) is a pre-invasive form of breast cancer where neoplastic luminal cells are confined to the ductal tree. While as many as 70% of DCIS cases will remain indolent, most women are treated with surgery, often combined with endocrine and radiotherapies. Overtreatment is therefore a major issue, demanding new methods to stratify patients. Somewhat paradoxically, the neoplastic cells in DCIS are genetically comparable to those in invasive disease, suggesting the tumour microenvironment is the driving force for progression. Clinical and mechanistic studies highlight the complex DCIS microenvironment, with multiple cell types competing to regulate progression. Here, we examine recent studies detailing distinct aspects of the DCIS microenvironment and discuss how these may inform more effective care.

Polysulfide Serves as a Hallmark of Desmoplastic Reaction to Differentially Diagnose Ductal Carcinoma In Situ and Invasive Breast Cancer by SERS Imaging

Pathological examination of formalin-fixed paraffin-embedded (FFPE) needle-biopsied samples by certified pathologists represents the gold standard for differential diagnosis between ductal carcinoma in situ (DCIS) and invasive breast cancers (IBC), while information of marker metabolites in the samples is lost in the samples. Infrared laser-scanning large-area surface-enhanced Raman spectroscopy (SERS) equipped with gold-nanoparticle-based SERS substrate enables us to visualize metabolites in fresh-frozen needle-biopsied samples with spatial matching between SERS and HE staining images with pathological annotations. DCIS (n = 14) and IBC (n = 32) samples generated many different SERS peaks in finger-print regions of SERS spectra among pathologically annotated lesions including cancer cell nests and the surrounding stroma. The results showed that SERS peaks in IBC stroma exhibit significantly increased polysulfide that coincides with decreased hypotaurine as compared with DCIS, suggesting that alterations of these redox metabolites account for fingerprints of desmoplastic reactions to distinguish IBC from DCIS. Furthermore, the application of supervised machine learning to the stroma-specific multiple SERS signals enables us to support automated differential diagnosis with high accuracy. The results suggest that SERS-derived biochemical fingerprints derived from redox metabolites account for a hallmark of desmoplastic reaction of IBC that is absent in DCIS, and thus, they serve as a useful method for precision diagnosis in breast cancer.

Cohort profile of the Sloane Project: methodology for a prospective UK cohort study of >15 000 women with screen-detected non-invasive breast neoplasia

PURPOSE

The introduction of breast screening in the UK led to an increase in the detection of non-invasive breast neoplasia, predominantly ductal carcinoma in situ (DCIS), a non-obligatory precursor of invasive breast cancer. The Sloane Project, a UK prospective cohort study of screen-detected non-invasive breast neoplasia, commenced in 2003 to evaluate the radiological assessment, surgical management, pathology, adjuvant therapy and outcomes for non-invasive breast neoplasia. Long-term follow-up and accurate data collection are essential to examine the clinical impact. Here, we describe the establishment, development and analytical processes for this large UK cohort study.

PARTICIPANTS

Women diagnosed with non-invasive breast neoplasia via the UK National Health Service Breast Screening Programme (NHSBSP) from 01 April 2003 are eligible, with a minimum age of 46 years. Diagnostic, therapeutic and follow-up data collected via proformas, complement date and cause of death from national data sources. Accrual for patients with DCIS ceased in 2012 but is ongoing for patients with epithelial atypia/in situ neoplasia, while follow-up for all continues long term.

FINDINGS TO DATE

To date, patients within the Sloane cohort comprise one-third of those diagnosed with DCIS within the NHSBSP and are representative of UK practice. DCIS has a variable outcome and confirms the need for longer-term follow-up for screen-detected DCIS. However, the radiology and pathology features of DCIS can be used to inform patient management. We demonstrate validation of follow-up information collected from national datasets against traditional, manual methods.

FUTURE PLANS

Conclusions derived from the Sloane Project are generalisable to women in the UK with screen-detected DCIS. The follow-up methodology may be extended to other UK cohort studies and routine clinical follow-up. Data from English patients entered into the Sloane Project are available on request to researchers under data sharing agreement. Annual follow-up data collection will continue for a minimum of 20 years.

Clinicopathologic Features, Treatment Patterns, and Disease Outcomes in a Modern, Prospective Cohort of Young Women Diagnosed with Ductal Carcinoma In Situ

BACKGROUND

Ductal carcinoma in situ (DCIS) is uncommon and understudied in young women. The objective of this study is to describe clinicopathologic features, treatment, and oncologic outcomes in a modern cohort of women aged ≤ 40 years with DCIS.

PATIENTS AND METHODS

Patients with DCIS were identified from the Young Women's Breast Cancer Study, a multisite prospective cohort of women diagnosed with stage 0-IV breast cancer at age ≤ 40 years, enrolled from 2006 to 2016. Clinical data were collected from patient surveys and medical records. Pathologic features were examined by central review. Data were summarized with descriptive statistics and groups were compared with χ² and Fisher's exact tests.

RESULTS

Among the 98 patients included, median age of diagnosis was 38 years; 36 (37%) patients were symptomatic on presentation. DCIS nuclear grade was high in 35%, intermediate in 50%, and low in 15% of lesions; 36% of lesions had comedonecrosis. The majority of patients underwent bilateral mastectomy (57%), 16 (16%) underwent unilateral mastectomy, and 26 (27%) underwent lumpectomy, most of whom received radiation. Few (13%) patients were receiving tamoxifen therapy 1 year postdiagnosis. Over a median follow-up of 8.4 years, six patients (6%) had disease recurrence, including five locoregional and one distant event.

CONCLUSIONS

A high proportion of young women with DCIS underwent mastectomy with or without contralateral prophylactic mastectomy. Although DCIS was frequently symptomatic on presentation and exhibited unfavorable pathologic factors, clinicopathologic features were overall heterogeneous and few recurrences occurred. This underscores the need for careful consideration of treatment options in young women with DCIS.

Learning to distinguish progressive and non-progressive ductal carcinoma in situ

Ductal carcinoma in situ (DCIS) is a non-invasive breast neoplasia that accounts for 25% of all screen-detected breast cancers diagnosed annually. Neoplastic cells in DCIS are confined to the ductal system of the breast, although they can escape and progress to invasive breast cancer in a subset of patients. A key concern of DCIS is overtreatment, as most patients screened for DCIS and in whom DCIS is diagnosed will not go on to exhibit symptoms or die of breast cancer, even if left untreated. However, differentiating low-risk, indolent DCIS from potentially progressive DCIS remains challenging. In this Review, we summarize our current knowledge of DCIS and explore open questions about the basic biology of DCIS, including those regarding how genomic events in neoplastic cells and the surrounding microenvironment contribute to the progression of DCIS to invasive breast cancer. Further, we discuss what information will be needed to prevent overtreatment of indolent DCIS lesions without compromising adequate treatment for high-risk patients.

The presentation, management and outcome of patients with ductal carcinoma in situ (DCIS) with microinvasion (invasion ≤1 mm in size)-results from the UK Sloane Project

BACKGROUND

The diagnosis, management and prognosis of microinvasive breast carcinoma remain controversial.

METHODS

We analysed the outcomes of patients with DCIS with and without microinvasion diagnosed between 2003 and 2012 within the Sloane project.

RESULTS

Microinvasion was recorded in 521 of 11,285 patients (4.6%), with considerable variation in reported incidence among screening units (0-25%). Microinvasion was associated with high-grade DCIS, larger DCIS size, comedo necrosis and solid, cribriform architecture (all P < 0.001). Microinvasion was more frequent in patients who underwent mastectomy compared with breast-conserving surgery (BCS) (6.9% vs 3.6%, P <  0.001), and in those undergoing axillary nodal surgery (60.4% vs 30.3%, P <  0.001) including the subset undergoing BCS (43.4% vs 8.5%, P < 0.001). Nodal metastasis rate was low and not statistically significant difference from the DCIS only group (P = 0.68). Following median follow-up of 110 months, 3% of patients had recurrent ipsilateral high-grade DCIS, and 4.2% developed invasive carcinoma. The subsequent ipsilateral invasion was of Grade 3 in 71.4% of patients with microinvasion vs 30.4% in DCIS without microinvasion (P = 0.02). Distant metastasis and breast cancer mortality were higher with microinvasion compared with DCIS only (1.2% vs 0.3%, P = 0.01 and 2.1% vs 0.8%; P = 0.005).

CONCLUSIONS

The higher breast cancer mortality with microinvasion indicates a more aggressive disease.

Is loss of p53 a driver of ductal carcinoma in situ progression?

Ductal carcinoma in situ (DCIS) is a non-obligate precursor of invasive carcinoma. Multiple studies have shown that DCIS lesions typically possess a driver mutation associated with cancer development. Mutation in the TP53 tumour suppressor gene is present in 15-30% of pure DCIS lesions and in ~30% of invasive breast cancers. Mutations in TP53 are significantly associated with high-grade DCIS, the most likely form of DCIS to progress to invasive carcinoma. In this review, we summarise published evidence on the prevalence of mutant TP53 in DCIS (including all DCIS subtypes), discuss the availability of mouse models for the study of DCIS and highlight the need for functional studies of the role of TP53 in the development of DCIS and progression from DCIS to invasive disease.

Genomic analysis defines clonal relationships of ductal carcinoma in situ and recurrent invasive breast cancer

Ductal carcinoma in situ (DCIS) is the most common form of preinvasive breast cancer and, despite treatment, a small fraction (5-10%) of DCIS patients develop subsequent invasive disease. A fundamental biologic question is whether the invasive disease arises from tumor cells in the initial DCIS or represents new unrelated disease. To address this question, we performed genomic analyses on the initial DCIS lesion and paired invasive recurrent tumors in 95 patients together with single-cell DNA sequencing in a subset of cases. Our data show that in 75% of cases the invasive recurrence was clonally related to the initial DCIS, suggesting that tumor cells were not eliminated during the initial treatment. Surprisingly, however, 18% were clonally unrelated to the DCIS, representing new independent lineages and 7% of cases were ambiguous. This knowledge is essential for accurate risk evaluation of DCIS, treatment de-escalation strategies and the identification of predictive biomarkers.

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.

Atypical Ductal Hyperplasia-Ductal Carcinoma In Situ Spectrum: Diagnostic Considerations and Treatment Impact in the Era of Deescalation

As the first node in treatment algorithms for breast disease, pathologists have the potential to play a critical role in refining appropriate therapy for lesions in the atypical ducal hyperplasia-ductal carcinoma in situ (ADH-DCIS) spectrum by conservatively approaching diagnosis of lesions limited in size on core needle biopsy. Appropriate efforts to downgrade the diagnosis of lesions at the borderline of ADH and DCIS will certainly lead to more breast conservation and avoid the common morbidities of mastectomy, sentinel node biopsy, and radiation therapy. Whether results of clinical trials of active surveillance will successfully identify a subset of women who may successfully forgo even limited breast-conserving surgery is eagerly anticipated. Given the increasing concern that a significant number of women with DCIS are overtreated, identification of patients at very low risk for progression who may forgo surgery and radiation therapy safely is of significant interest.

Unresected screen-detected ductal carcinoma in situ: Outcomes of 311 women in the Forget-Me-Not 2 study

BACKGROUND AND AIM

The natural history of ductal carcinoma in situ (DCIS) is poorly understood. The aim of this cohort study was to determine the outcomes of women who had no surgery for screen-detected DCIS in the 6 months following diagnosis.

METHODS

English breast screening databases were retrospectively searched for women diagnosed with DCIS without invasive cancer at screening and who had no record of surgery within 6 months of diagnosis. These were cross-referenced with cancer registry data. Details of the potentially eligible women were sent to the relevant breast screening units for verification and for completion of data forms detailing clinical, radiological and pathological findings, non-surgical treatment and subsequent clinical course.

RESULTS

Data for 311 eligible women (median age 62 years) were available. 60 women developed invasive cancer, 56 ipsilateral and 4 contralateral. Ipsilateral invasion risk increased approximately linearly with time for at least 10 years. The 10-year cumulative risk of ipsilateral invasion was 9% (95% CI 4-21%), 39% (24-58%) and 36% (24-50%) for low, intermediate and high grade DCIS respectively and was higher in younger women, in those with larger DCIS lesions and in those with microinvasion. Most invasive cancers that developed were grade 2 or 3.

CONCLUSION

The findings suggest that active surveillance may be a reasonable alternative to surgery in patients with low grade DCIS but that women with intermediate or high grade disease should continue to be offered surgery. This highlights the importance of reproducible grading of DCIS to ensure patients receive appropriate treatment.

A deep learning model for breast ductal carcinoma in situ classification in whole slide images

The pathological differential diagnosis between breast ductal carcinoma in situ (DCIS) and invasive ductal carcinoma (IDC) is of pivotal importance for determining optimum cancer treatment(s) and clinical outcomes. Since conventional diagnosis by pathologists using microscopes is limited in terms of human resources, it is necessary to develop new techniques that can rapidly and accurately diagnose large numbers of histopathological specimens. Computational pathology tools which can assist pathologists in detecting and classifying DCIS and IDC from whole slide images (WSIs) would be of great benefit for routine pathological diagnosis. In this paper, we trained deep learning models capable of classifying biopsy and surgical histopathological WSIs into DCIS, IDC, and benign. We evaluated the models on two independent test sets (n= 1382, n= 548), achieving ROC areas under the curves (AUCs) up to 0.960 and 0.977 for DCIS and IDC, respectively.

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.

Accounting for Preinvasive Conditions in Analysis of Invasive Cancer Risk: Application to Breast Cancer

BACKGROUND

Preinvasive cancer conditions are often actively treated to minimize progression to life-threatening invasive cancers, but this creates challenges for analysis of invasive cancer risk. Conventional methods of treating preinvasive conditions as censoring events or targeting at the composite outcome could both lead to bias.

METHODS

We propose two solutions: one that provides exact estimates of risk based on distributional assumptions about progression, and one that provides risk bounds corresponding to extreme cases of no or complete progression. We compare these approaches through simulations and an analysis of the Sister Study data in the context of ductal carcinoma in situ (DCIS) and invasive breast cancer.

RESULTS

Simulations suggested important biases with conventional approaches, whereas the proposed estimate is consistent when progression parameters are correctly specified, and the risk bounds are robust in all scenarios. With Sister Study, the estimated lifetime risks for invasive breast cancer are 0.220 and 0.269 with DCIS censored or combined. Without detailed progression information, a sensitivity analysis suggested lifetime risk falls between the bounds of 0.214 and 0.269 across assumptions of 10%-95% of DCIS patients progressing to invasive cancer in an average of 1-10 years.

CONCLUSIONS

When estimating invasive cancer risk while preinvasive conditions are actively treated, it is important to consider the implied assumptions and potential biases of conventional approaches. Although still not perfect, we proposed two practical solutions that provide improved understanding of the underlying mechanism of invasive cancer.

Long-term risk of subsequent ipsilateral lesions after surgery with or without radiotherapy for ductal carcinoma in situ of the breast

BACKGROUND

Radiotherapy (RT) following breast-conserving surgery (BCS) for ductal carcinoma in situ (DCIS) reduces ipsilateral breast event rates in clinical trials. This study assessed the impact of DCIS treatment on a 20-year risk of ipsilateral DCIS (iDCIS) and ipsilateral invasive breast cancer (iIBC) in a population-based cohort.

METHODS

The cohort comprised all women diagnosed with DCIS in the Netherlands during 1989-2004 with follow-up until 2017. Cumulative incidence of iDCIS and iIBC following BCS and BCS + RT were assessed. Associations of DCIS treatment with iDCIS and iIBC risk were estimated in multivariable Cox models.

RESULTS

The 20-year cumulative incidence of any ipsilateral breast event was 30.6% (95% confidence interval (CI): 28.9-32.6) after BCS compared to 18.2% (95% CI 16.3-20.3) following BCS  +  RT. Women treated with BCS compared to BCS + RT had higher risk of developing iDCIS and iIBC within 5 years after DCIS diagnosis (for iDCIS: hazard ratio (HR)_age < 50 3.2 (95% CI 1.6-6.6); HR_{age ≥ 50} 3.6 (95% CI 2.6-4.8) and for iIBC: HR_age<50 2.1 (95% CI 1.4-3.2); HR_{age ≥ 50} 4.3 (95% CI 3.0-6.0)). After 10 years, the risk of iDCIS and iIBC no longer differed for BCS versus BCS + RT (for iDCIS: HR_age < 50 0.7 (95% CI 0.3-1.5); HR_{age ≥ 50} 0.7 (95% CI 0.4-1.3) and for iIBC: HR_age < 50 0.6 (95% CI 0.4-0.9); HR_{age ≥ 50} 1.2 (95% CI 0.9-1.6)).

CONCLUSION

RT is associated with lower iDCIS and iIBC risk up to 10 years after BCS, but this effect wanes thereafter.

Factors involved in treatment decision making for women diagnosed with ductal carcinoma in situ: A qualitative study

Whilst some of the diversity in management of women with ductal carcinoma in situ (DCIS) may be explained by tumour characteristics, the role of patient preference and the factors underlying those preferences have been less frequently examined. We have used a descriptive qualitative study to explore treatment decisions for a group of Australian women diagnosed with DCIS through mammographic screening. Semi-structured telephone interviews were performed with 16 women diagnosed with DCIS between January 2012 and December 2018, recruited through the LifePool dataset (a subset of BreastScreen participants who have agreed to participate in research). Content analysis using deductive coding identified three themes: participants did not have a clear understanding of their diagnosis or prognosis; reported involvement in decision making about management varied; specific factors including the psychosexual impact of mastectomy and perceptions of radiotherapy, could act as barriers or facilitators to specific decisions about treatment. The treatment the women received was not simply determined by the characteristics of their disease. Interaction with the managing clinician was pivotal, however many other factors played a part in individual decisions. Recognising that decisions are not purely a function of disease characteristics is important for both women with DCIS and the clinicians who care for them.

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.

Usefulness of supplementary ultrasound surveillance in the detection of a second breast cancer in patients with ductal carcinoma in situ

INTRODUCTION

Supplementary ultrasound surveillance in breast cancer patients can detect additional cancers but is associated with unnecessary biopsies and follow-ups. We aim to determine, in patients with ductal carcinoma in situ (DCIS), the prevalence and factors associated with second breast cancers and the usefulness of supplementary ultrasound surveillance. This is the first study which focused on the usefulness of ultrasound surveillance in DCIS patients.

METHODS

DCIS patients were retrospectively analyzed to determine the prevalence and factors associated with second breast cancers. The prevalence of patients with benign biopsies, additional ultrasound follow-ups and second breast cancers, resulting from ultrasound surveillance, were calculated.

RESULTS

Three hundred and thirty- two patients were included. 25 (7.5%) patients developed second breast cancers after a mean follow-up of 77.7 months. Breast conservation (P= .0218), involved margins after lumpectomy (P = .0003) and shortened hormonal therapy (P= 0.0369) were associated with second cancers. Of the 314 patients who had ultrasound surveillance, ipsilateral, and contralateral ultrasounds yielded 1.7%/1.3% cancer detection, 5.8%/6.7% benign biopsies and 10.4%/15.3% additional follow-ups. Patients with involved margins after lumpectomy have ipsilateral cancer detection, benign biopsies and additional follow-ups of 4.5%, 4.5%, and 9.1% respectively. A total of 85.4% patients had mammographically dense breasts.

CONCLUSION

In DCIS patients, the rate of second breast cancers was 7.5%. Breast conservation, involved margins after lumpectomy and shortened hormonal therapy were associated with second cancers. Patients with involved margins after lumpectomy have the highest cancer detection rate and minimal unnecessary biopsies and follow-ups. Hence, ipsilateral breast ultrasound surveillance could be personalized for this high-risk group with mammographically dense breasts.

Is There Any Association Between Mammographic Features of Microcalcifications and Breast Cancer Subtypes in Ductal Carcinoma In Situ?

RATIONALE AND OBJECTIVES

To analyze the association between mammographic features of microcalcifications and histopathological prognostic factors based on estrogen receptor (ER) and human epidermal growth factor receptor 2 (HER2/neu) in ductal carcinoma in situ (DCIS).

MATERIALS AND METHODS

We retrospectively determined 66 patients with microcalcification-associated pure DCIS. Distribution and morphological features of the microcalcifications were described using Breast Imaging Reporting and Data System lexicon. All patients were divided into three subgroups: ER-positive, HER-2 positive, and triple-negative according to the immunohistochemical findings.

RESULTS

The morphological features of microcalcifications and receptor subtypes were significantly correlated (p = 0.026). Fine pleomorphic and fine linear branching microcalcifications were observed in 85.2% of HER-2 positive cases, whereas this ratio was 71.4 % in ER-positive and 25% in the triple-negative group. Fine linear branching microcalcifications with linear or segmental distribution were more frequently found with comedo necrosis (p < 0.05). Larger tumour sizes were also associated with microcalcification distribution (p < 0.001). Segmental microcalcifications more likely associated with larger tumour sizes.

CONCLUSION

Mammographic features in DCIS correlated with immunohistochemical and histopathological prognostic factors.

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.

Variability in grading of ductal carcinoma in situ among an international group of pathologists

The prognostic value of cytonuclear grade in ductal carcinoma in situ (DCIS) is debated, partly due to high interobserver variability and the use of multiple guidelines. The aim of this study was to evaluate interobserver agreement in grading DCIS between Dutch, British, and American pathologists. Haematoxylin and eosin-stained slides of 425 women with primary DCIS were independently reviewed by nine breast pathologists based in the Netherlands, the UK, and the USA. Chance-corrected kappa (κma ) for association between pathologists was calculated based on a generalised linear mixed model using the ordinal package in R. Overall κma for grade of DCIS (low, intermediate, or high) was estimated to be 0.50 (95% confidence interval [CI] 0.44-0.56), indicating a moderate association between pathologists. When the model was adjusted for national guidelines, the association for grade did not change (κma = 0.53; 95% CI 0.48-0.57); subgroup analysis for pathologists using the UK pathology guidelines only had significantly higher association (κma = 0.58; 95% CI 0.56-0.61). To assess if concordance of grading relates to the expression of the oestrogen receptor (ER) and HER2, archived immunohistochemistry was analysed on a subgroup (n = 106). This showed that non-high grade according to the majority opinion was associated with ER positivity and HER2 negativity (100 and 89% of non-high grade cases, respectively). In conclusion, DCIS grade showed only moderate association using whole slide images scored by nine breast pathologists. As therapeutic decisions and inclusion in ongoing clinical trials are guided by DCIS grade, there is a pressing need to reduce interobserver variability in grading. ER and HER2 might be supportive to prevent the accidental and unwanted inclusion of high-grade DCIS in such trials.

Breast MRI in DCIS size estimation, breast-conserving surgery and oncoplastic breast surgery

The impact of MRI on improving surgical outcomes in DCIS is debated. Here, we explore the utility of MRI in the investigation and management of DCIS in three key areas. Firstly, we highlight that MRI is likely to be a more accurate predictor of actual tumour size than conventional imaging. Secondly, we examine mastectomy rates and reoperation rates across the literature and suggest that surgical outcomes do not differ between pre-operative MRI and conventional imaging groups, despite improved size estimation on MRI. Finally, we examine the rapidly developing field of oncoplastic breast surgery and highlight a paucity of data in determining the usefulness of pre-operative MRI in this field, despite this being an oncologically safe alternative with improved patient outcomes and satisfaction.

The Selection of Treatment Modality for Breast Ductal Carcinoma In Situ: Experience From a Single Institution

PURPOSE

Although breast conservation surgery(BCS) followed by adjuvant radiotherapy is now the mainstream treatment method for breast ductal carcinoma in situ(DCIS), mastectomy is still performed in some patients who refuse to undergo radiation. However, the most effective treatment method for these patients is still unknown. In the current study, we aimed to compare the survival rates between mastectomy and BCS plus adjuvant radiotherapy in patients with DCIS.

MATERIALS AND METHODS

We performed a retrospective study of 333 patients with DCIS from May 2004 to December 2016. There were 209 patents who were treated with BCS and adjuvant radiotherapy, while the remaining of 124 patients underwent mastectomy. The disease-free survival (DFS) and local recurrence-free survival(LRFS) rates were compared between the 2 treatment groups. Cox proportional hazards regression was performed to explore factors associated with DFS and LRFS.

RESULTS

The 10-year local recurrence(LR) rates in the mastectomy and BCS plus adjuvant radiotherapy groups were 2.6% and 7.5%, respectively. There was no difference in the LR rate between the 2 groups. Furthermore the DFS rate was also similar between the mastectomy and BCS plus adjuvant radiotherapy groups. Based on the multivariable analysis, age and tumor grade were significantly correlated with the LRFS and DFS rates. In the subgroup analysis based on the factors of age and tumor grade, patients with a tumor grade of III who underwent mastectomy had better LRFS and DFS rates compared to those who received BCS plus radiotherapy.

CONCLUSION

In patients with DCIS, the long-term efficacy was similar between mastectomy and BCS followed by adjuvant radiotherapy. However, in the subgroup of patients with grade III tumors, mastectomy seems to offer a better LRFS and DFS than BCS plus radiotherapy.

21-Gene Assay and Breast Cancer Mortality in Ductal Carcinoma In Situ

BACKGROUND

The inability to identify individuals with ductal carcinoma in situ (DCIS) who are at risk of breast cancer (BC) mortality have hampered efforts to reduce the overtreatment of DCIS. The 21-gene recurrence score (RS) predicts distant metastases for individuals with invasive BC, but its prognostic utility in DCIS is unknown.

METHODS

We performed a population-based analysis of 1362 individuals of DCIS aged 75 years or younger at diagnosis treated with breast-conserving therapy. We examined the association between a high RS (defined a priori as >25) and the risk of BC mortality by using a propensity score-adjusted model accounting for the competing risk of death from other causes, testing for interactions. All statistical tests were 2-sided.

RESULTS

With 16 years median follow-up, 36 (2.6%) died of BC, and 200 (14.7%) died of other causes. The median value of the RS was 15 (range = 0-84); 29.6% of individuals had a high RS. A high RS was associated with an 11-fold increased risk of BC mortality (hazard ratio = 11.27, 95% confidence interval [CI] = 3.00 to 42.33; P < .001) in women aged 50 years or younger at diagnosis treated with breast-conserving surgery alone, culminating in a 9.4% (95% CI = 2.3% to 22.5%) 20-year risk of BC death. For women with a high RS, treatment with radiotherapy was associated with a 71% (hazard ratio = 0.29, 95% CI = 0.10 to 0.89; P = .03) relative and a 5% absolute reduction in the 20-year cumulative risk of death from BC.

CONCLUSION

The 21-gene RS predicts BC mortality in DCIS and combined with age (50 years or younger) at diagnosis can identify individuals for whom radiotherapy reduces the risk of death from BC.

Pathological features of 11,337 patients with primary ductal carcinoma in situ (DCIS) and subsequent events: results from the UK Sloane Project

Background

The Sloane audit compares screen-detected ductal carcinoma in situ (DCIS) pathology with subsequent management and outcomes.

Methods

This was a national, prospective cohort study of DCIS diagnosed during 2003–2012.

Results

Among 11,337 patients, 7204 (64%) had high-grade DCIS. Over time, the proportion of high-grade disease increased (from 60 to 65%), low-grade DCIS decreased (from 10 to 6%) and mean size increased (from 21.4 to 24.1 mm). Mastectomy was more common for high-grade (36%) than for low-grade DCIS (15%). Few (6%) patients treated with breast-conserving surgery (BCS) had a surgical margin <1 mm. Of the 9191 women diagnosed in England (median follow-up 9.4 years), 7% developed DCIS or invasive malignancy in the ipsilateral and 5% in the contralateral breast. The commonest ipsilateral event was invasive carcinoma (n = 413), median time 62 months, followed by DCIS (n = 225), at median 37 months. Radiotherapy (RT) was most protective against recurrence for high-grade DCIS (3.2% for high-grade DCIS with RT compared to 6.9% without, compared with 2.3 and 3.0%, respectively, for low/intermediate-grade DCIS). Ipsilateral DCIS events lessened after 5 years, while the risk of ipsilateral invasive cancer remained consistent to beyond 10 years.

Conclusion

DCIS pathology informs patient management and highlights the need for prolonged follow-up of screen-detected DCIS.

Tumor-Infiltrating Lymphocytes (TILs) and Risk of a Second Breast Event After a Ductal Carcinoma in situ

Women with a diagnosis of ductal carcinoma in situ (DCIS) have a high risk of developing a second breast event (SBE). The immune system might play a role in trying to prevent a SBE. Patients diagnosed with DCIS were identified in the population-based cancer registry of Area Vasta Romagna from 1997 to 2010. Median follow-up is 8.5 years. Tumor-infiltrating lymphocytes (TILs) were evaluated both in index DCIS and in SBE. The main endpoint was to assess the association between TILs' levels in index DCIS and risk of a SBE. Out of 496 DCIS patients, 100 SBEs (20.2%) were identified: 55 ipsilateral (11.1%) and 43 contralateral (8.7%). The distribution of TILs was heterogeneous, but significantly associated with grade, necrosis, screen detection and type of surgery. Patients stratified according to TILs percentage (≤5% and >5%) did not show a statistically significant difference in the 5-year cumulative incidence of SBEs: 14.9% (95% CI 11.3–19.1) and 11.0% (95% CI, 6.9–16.2), respectively (p = 0.147). In the subgroup of patients who did not receive radiotherapy, TILs >5% were associated with a reduced risk of SBE (HR 0.34, 95% CI 0.14–0.82, p = 0.016). Although we did not find any significant association between TILs and SBE, further studies evaluating their role according to radiotherapy are warranted.

The clinical significance of oestrogen receptor expression in breast ductal carcinoma in situ

Background

Oestrogen receptor (ER) in invasive breast cancer (BC) predicts response to endocrine therapy (ET) and provides prognostic value. In this study, we investigated the value of ER expression in ductal carcinoma in situ (DCIS) in terms of outcome and the impact on ET decision.

Methods

In total, 643 pure DCIS, diagnosed at Nottingham University Hospitals, were assessed for ER. Clinicopathological data were correlated against ER status, together with assessment of recurrence rate.

Results

ER positivity was observed in 74% (475/643) of cases. ER positivity was associated with clinicopathological variables of good prognosis; however, outcome analysis revealed that ER status was not associated with local recurrence. In the intermediate- and high-grade ER-positive DCIS, 58% (11/19) and 63% (15/24) of the recurrences were invasive, respectively, comprising 7% and 6% of all ER-positive DCIS, respectively. Invasive recurrence in low-grade DCIS was infrequent (2%), and none of these patients died of BC. The ER status of the recurrent invasive tumours matched the primary DCIS ER status (94% in ipsilateral and 90% of contralateral recurrence).

Conclusion

The strong correlation between DCIS and invasive recurrence ER status and the clinical impact of ET justify discussion of the use of ET in ER-positive DCIS treated by breast-conserving surgery. The excellent outcome of low-grade DCIS, which was almost always ER-positive, does not, in the opinion of authors, justify the use of risk-reducing ET. Therefore, the decision on ET for DCIS should be personalised and consider grade, ER status and other characteristics.

Long-term Survival Outcomes of 'Low Risk' Ductal Carcinoma in situ from a Territory-wide Cancer Registry

AIMS

The LORIS trial is an ongoing phase III clinical trial on low risk ductal carcinoma in situ (DCIS). DCIS patients aged ≥46 years with screen-detected low/intermediate nuclear grade were considered low risk and were randomised into surveillance or standard surgery. Here we review the 10-year territory-wide breast cancer registry database and evaluate the clinical outcomes of low versus high risk DCIS patients.

MATERIALS AND METHODS

This was a retrospective study of a prospectively maintained territory-wide breast cancer registry in Hong Kong.

RESULTS

Between 1997 and 2006, 1391 DCIS patients were identified from the Hong Kong cancer registry breast cancer database. The mean age at diagnosis was 49.2 years (range 30-70). In total, 372 patients were classified as 'low risk', whereas the remaining 777 patients were classified as 'high risk'. After a median follow-up of 11.6 years, the 10-year overall breast cancer-specific survival of the entire DCIS cohort was 1136/1149 (98.9%). Overall breast cancer-specific survival of low risk DCIS was 99.5%, whereas that in high risk DCIS was 98.6% (Log-rank test, P = 0.208). Forty-six (12.4%) patients in the LORIS low risk group did not receive surgery, whereas 93 (12%) patients in the LORIS high risk group did not receive surgery. The 10-year breast cancer-specific survival in the non-operated low risk DCIS group was 97.8%; that in the non-operated high risk DCIS group was 96.7% (P = 1).

CONCLUSION

Long-term survival of DCIS was excellent, especially in low risk DCIS, regardless of surgical treatment.

The challenge of avoiding over- and under-treatment in older women with ductal cancer in situ: A scoping review of existing knowledge gaps and a meta-analysis of real-world practice patterns

Ductal cancer in situ (DCIS) is mainly a screen-detected disease and although the risk for breast cancer is age-dependent, most screening programs do not include women over the age of 75 years. Older women are usually excluded from clinical trials and treatment practices are largely based on observational studies or extrapolation of trial results from younger patients, leading to either over- or under-treatment of this population. We systematically reviewed available electronic databases for DCIS treatment patterns and outcomes in older patients 15 years. Inclusion criteria allowed for randomised controlled trials, cohort studies, case-control and cross-sectional studies, as well as meta-analyses, systematic reviews and position papers. Results showed that, although elderly are not necessarily frail, they are generally treated as such by physicians, aiming to de-escalate therapeutic interventions. After adjusting for frailty, age seems to be a significant factor for less surgery; however, older women with DCIS are more probable to receive surgery than their counterparts with early invasive cancer. DCIS biology and subtypes are independent risk factors for local recurrence or progression to invasive carcinoma, if DCIS is under-treated. The end-benefit of surgery, radio- and endocrine-therapy depend on additional parameters, such as life expectancy, co-morbidities and competing risks of death. Screen-detected DCIS in older women is a challenging clinical problem, mainly due to the lack of high-level data. Therapeutic strategies should be tailored to life expectancy and performance status, DCIS features and patient preference, aiming at combining optimal oncological outcomes with maintenance of quality of life.

Invasive breast cancer and breast cancer mortality after ductal carcinoma in situ in women attending for breast screening in England, 1988-2014: population based observational cohort study

OBJECTIVE

To evaluate the long term risks of invasive breast cancer and death from breast cancer after ductal carcinoma in situ (DCIS) diagnosed through breast screening.

DESIGN

Population based observational cohort study.

SETTING

Data from the NHS Breast Screening Programme and the National Cancer Registration and Analysis Service.

PARTICIPANTS

All 35 024 women in England diagnosed as having DCIS by the NHS Breast Screening Programme from its start in 1988 until March 2014.

MAIN OUTCOME MEASURES

Incident invasive breast cancer and death from breast cancer.

RESULTS

By December 2014, 13 606 women had been followed for up to five years, 10 998 for five to nine years, 6861 for 10-14 years, 2620 for 15-19 years, and 939 for at least 20 years. Among these women, 2076 developed invasive breast cancer, corresponding to an incidence rate of 8.82 (95% confidence interval 8.45 to 9.21) per 1000 women per year and more than double that expected from national cancer incidence rates (ratio of observed rate to expected rate 2.52, 95% confidence interval 2.41 to 2.63). The increase started in the second year after diagnosis of DCIS and continued until the end of follow-up. In the same group of women, 310 died from breast cancer, corresponding to a death rate of 1.26 (1.13 to 1.41) per 1000 women per year and 70% higher than that expected from national breast cancer mortality rates (observed:expected ratio 1.70, 1.52 to 1.90). During the first five years after diagnosis of DCIS, the breast cancer death rate was similar to that expected from national mortality rates (observed:expected ratio 0.87, 0.69 to 1.10), but it then increased, with values of 1.98 (1.65 to 2.37), 2.99 (2.41 to 3.70), and 2.77 (2.01 to 3.80) in years five to nine, 10-14, and 15 or more after DCIS diagnosis. Among 29 044 women with unilateral DCIS undergoing surgery, those who had more intensive treatment (mastectomy, radiotherapy for women who had breast conserving surgery, and endocrine treatment in oestrogen receptor positive disease) and those with larger final surgical margins had lower rates of invasive breast cancer.

CONCLUSIONS

To date, women with DCIS detected by screening have, on average, experienced higher long term risks of invasive breast cancer and death from breast cancer than women in the general population during a period of at least two decades after their diagnosis. More intensive treatment and larger final surgical margins were associated with lower risks of invasive breast cancer.

Discordant Marker Expression Between Invasive Breast Carcinoma and Corresponding Synchronous and Preceding DCIS

Ductal carcinoma in situ (DCIS) is considered a potential precursor of invasive breast carcinoma (IBC). Studies aiming to find markers involved in DCIS progression generally have compared characteristics of IBC lesions with those of adjacent synchronous DCIS lesions. The question remains whether synchronous DCIS and IBC comparisons are a good surrogate for primary DCIS and subsequent IBC. In this study, we compared both primary DCIS and synchronous DCIS with the associated IBC lesion, on the basis of immunohistochemical marker expression. Immunohistochemical analysis of ER, PR, HER2, p53, and cyclo-oxygenase 2 (COX-2) was performed for 143 primary DCIS and subsequent IBC lesions, including 81 IBC lesions with synchronous DCIS. Agreement between DCIS and IBC was assessed using kappa, and symmetry tests were performed to assess the pattern in marker conversion. The primary DCIS and subsequent IBC more often showed discordant marker expression than synchronous DCIS and IBC. Strikingly, 18 of 49 (36%) women with HER2-positive primary DCIS developed an HER2-negative IBC. Such a difference in HER2 expression was not observed when comparing synchronous DCIS and IBC. The frequency of discordant marker expression did not increase with longer time between primary DCIS and IBC. In conclusion, comparison of primary DCIS and subsequent IBC yields different results than a comparison of synchronous DCIS and IBC, in particular with regard to HER2 status. To gain more insight into the progression of DCIS to IBC, it is essential to focus on the relationship between primary DCIS and subsequent IBC, rather than comparing IBC with synchronous DCIS.

[Ductal carcinoma in situ in 2019: Diagnosis, treatment, prognosis]

Ductal carcinoma in situ (DCIS) currently represents up to 15% of the newly diagnosed breast cancers, and are almost always detected by microcalcifications. Global prognosis is good (3% of 15-year specific mortality) but invasive local recurrences (LR) can lead to metastasis in 12-15% of the cases. Breast conserving surgery with whole breast irradiation is the main treatment (reducing LR by 50%), but mastectomy (with or without reconstruction) is performed in about 30% of the cases due to wide lesion size and/or multicentricity. The role of tamoxifen remains unclear. Axillary dissection is needless but sentinel node biopsy is proposed in case of micro-invasion suspicion (large lesions with high grade). The main factors of LR are young age (≤40 years) incomplete excision, and high nuclear grade with comedonecrosis. Several studies on "therapeutic descalation" are still ongoing in order to identify the "low risk" DCIS (about 10% of the cases) in which radiotherapy could be safely omitted.