Cause-specific Mortality in a Population-based Cohort of 9799 Women Treated for Ductal Carcinoma In Situ

Ductal carcinoma in situ and cause-specific mortality among younger and older postmenopausal women: the Women's Health Initiative

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

The Clinical Utility of a 7-Gene Biosignature on Radiation Therapy Decision Making in Patients with Ductal Carcinoma In Situ Following Breast-Conserving Surgery: An Updated Analysis of the DCISionRT® PREDICT Study

BACKGROUND

Breast-conserving surgery (BCS) followed by adjuvant radiotherapy (RT) is a standard treatment for ductal carcinoma in situ (DCIS). A low-risk patient subset that does not benefit from RT has not yet been clearly identified. The DCISionRT test provides a clinically validated decision score (DS), which is prognostic of 10-year in-breast recurrence rates (invasive and non-invasive) and is also predictive of RT benefit. This analysis presents final outcomes from the PREDICT prospective registry trial aiming to determine how often the DCISionRT test changes radiation treatment recommendations.

METHODS

Overall, 2496 patients were enrolled from February 2018 to January 2022 at 63 academic and community practice sites and received DCISionRT as part of their care plan. Treating physicians reported their treatment recommendations pre- and post-test as well as the patient's preference. The primary endpoint was to identify the percentage of patients where testing led to a change in RT recommendation. The impact of the test on RT treatment recommendation was physician specialty, treatment settings, individual clinical/pathological features and RTOG 9804 like criteria. Multivariate logisitc regression analysis was used to estimate the odds ratio (ORs) for factors associated with the post-test RT recommendations.

RESULTS

RT recommendation changed 38% of women, resulting in a 20% decrease in the overall recommendation of RT (p < 0.001). Of those women initially recommended no RT (n = 583), 31% were recommended RT post-test. The recommendation for RT post-test increased with increasing DS, from 29% to 66% to 91% for DS <2, DS 2-4, and DS >4, respectively. On multivariable analysis, DS had the strongest influence on final RT recommendation (odds ratio 22.2, 95% confidence interval 16.3-30.7), which was eightfold greater than clinicopathologic features. Furthermore, there was an overall change in the recommendation to receive RT in 42% of those patients meeting RTOG 9804-like low-risk criteria.

CONCLUSIONS

The test results provided information that changes treatment recommendations both for and against RT use in large population of women with DCIS treated in a variety of clinical settings. Overall, clinicians changed their recommendations to include or omit RT for 38% of women based on the test results. Based on published clinical validations and the results from current study, DCISionRT may aid in preventing the over- and undertreatment of clinicopathological 'low-risk' and 'high-risk' DCIS patients.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT03448926 ( https://clinicaltrials.gov/study/NCT03448926 ).

Ductal carcinoma in situ of the breast: finding the balance between overtreatment and undertreatment

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

Adherence to guideline recommendations for follow-up in patients with DCIS at a large teaching hospital in the Netherlands

PURPOSE

Ductal-carcinoma in situ (DCIS) is a pre-invasive form of breast cancer with good prognosis. Follow-up guidelines in the Netherlands are currently the same as for invasive breast cancer. Due to fear of invasive breast cancer or recurrence, it is hypothesized that follow-up for DCIS after treatment is more intense in practice resulting in potentially unnecessary high costs. This study investigates the follow-up in practice for patients with DCIS compared to the recommendations in order to inform clinicians and policy makers how to utilize these guidelines.

METHODS

Patients diagnosed with pure DCIS between 2004 and 2014 were followed up until 2018. Information on duration and frequency of follow-up visits, reasons and decision makers for shortening, and prolonging follow-up was collected. Prolonged follow-up was defined as deviation from the Dutch guideline: more than 5 years of follow-up and older than 60 years.

RESULTS

Of the 227 patients the mean number of visits per year was 1.4 and mean years of follow-up was 6.0. Thirty-three percent had prolonged follow-up and 26% shorter follow-up than recommended. A majority (78%) of decision for prolonged follow-up was being made by clinicians.

CONCLUSION

Follow-up duration is in almost half of patients with DCIS according to guidelines and with most prolonged follow-up only up to a year longer than recommended. In most cases suspicious findings and the timing of the population screening program appeared to cause prolonged follow-up. If accepted by patients and clinicians, future DCIS specific guidelines should address these reasons and tailor to the individual risks.

Surgical margin and local recurrence of ductal carcinoma in situ

PURPOSE

This study aims to evaluate the association between surgical margin status and local recurrence of DCIS.

METHODS

A retrospective analysis of a prospectively maintained 20-year DCIS database was performed. >=2 mm margin was defined as clear margin. Local relapse rate between the patients with clear versus close margins were analyzed with Kaplan-Meier analyses.

RESULTS

654 patients were analyzed. Median age was 46.5 (Range 18 - 80). 205 (31.3%) were high grade, 194 (29.7%) were intermediate grade, 143 (21.9%) were low grade. 112 (18.3%) were unknown. 202 (30.9%) were estrogen receptor positive, 49 (7.4%) were negative, 403 (61.6%) patients were unknown. 403 (61.6%) patients received mastectomy while 251 (38.4%) patients received BCS and radiotherapy. 549 (83.9%) patients had clear surgical margin, 50 (7.7%) patients had involved (positive) resection margin, 55 (8.4%) had close margin (<2 mm margin). All patients with involved margin received re-excision of margin, while 21 patients (out of 55 who had close resection margins) received re-excision of margin. Negative surgical margins were achieved after the re-excision. 34 patients with close resection margin decided not to receive re-excision but to undergo adjuvant radiotherapy. After median follow-up of 128 months, the 10-year ipsilateral breast tumor relapse (IBTR) was 4.5% (N = 28), Of which 27 (96.4%) patients had clear margin after the initial surgical treatment of DCIS. 1 (3.6%) patient had close surgical margin. Difference in IBTR between the two groups was not statistically significant (p = 0.692).

CONCLUSION

Close surgical margin for DCIS is not associated with increased risk of IBTR.

Long-term follow-up of complex oncoplastic breast-conserving surgery, standard breast conservation and skin-sparing mastectomy in DCIS - a register-based study

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

Peripheral blood TCR clonotype diversity as an age-associated marker of breast cancer progression

Immune escape is a prerequisite for tumor growth. We previously described a decline in intratumor activated cytotoxic T cells and T cell receptor (TCR) clonotype diversity in invasive breast carcinomas compared to ductal carcinoma in situ (DCIS), implying a central role of decreasing T cell responses in tumor progression. To determine potential associations between peripheral immunity and breast tumor progression, here, we assessed the peripheral blood TCR clonotype of 485 breast cancer patients diagnosed with either DCIS or de novo stage IV disease at younger (<45) or older (≥45) age. TCR clonotype diversity was significantly lower in older compared to younger breast cancer patients regardless of tumor stage at diagnosis. In the younger age group, TCR-α clonotype diversity was lower in patients diagnosed with de novo stage IV breast cancer compared to those diagnosed with DCIS. In the older age group, DCIS patients with higher TCR-α clonotype diversity were more likely to have a recurrence compared to those with lower diversity. Whole blood transcriptome profiles were distinct depending on the TCR-α Chao1 diversity score. There were more CD8+ T cells and a more active immune environment in DCIS tumors of young patients with higher peripheral blood TCR-α Chao1 diversity than in those with lower diversity. These results provide insights into the role that host immunity plays in breast cancer development across different age groups.

Human Ductal Carcinoma In Situ: Advances and Future Perspectives

Due to widespread adoption of screening mammography, there has been a significant increase in new diagnoses of ductal carcinoma in situ (DCIS). However, DCIS outcomes remain unclear. A large fraction of human DCIS (>50%) may not need the multimodality treatment options currently offered to all DCIS patients. More importantly, while we may be overtreating many, we cannot identify those most at risk of invasion or metastasis following a DCIS diagnosis. This review summarizes the studies that have furthered our understanding of DCIS pathology and mechanisms of invasive progression by using advanced technologies including spatial genomics, transcriptomics, and multiplex proteomics. This review also highlights a need for rethinking DCIS with a more focused view on epithelial states and programs and their cross talk with the microenvironment.

Net survival of women diagnosed with breast tumours: a population-based study in Switzerland

AIMS OF THE STUDY

Although the incidence of breast carcinoma in situ has been increasing, the prognosis of breast carcinoma in situ patients has not been extensively investigated. Thus, we aimed to compare the characteristics of invasive breast tumours based on whether or not they were preceded by a breast carcinoma in situ and to estimate the 5-year net survival of patients diagnosed with different breast tumours.

METHODS

Data from women diagnosed with breast tumours between 2003 and 2016 were used in our analyses. Net survival analyses were performed using inverse probability of censoring weights (nonparametric Pohar Perme estimator). Under certain assumptions, differences in survival between the cancer population and the general population can be considered to be attributable to the cancer diagnosis (NS).

RESULTS

Descriptive observation of tumour characteristics indicated that invasive breast tumours following a breast carcinoma in situ were more frequently detected at an earlier stage and had less missing information in tumour-specific variables, compared to invasive breast tumours not preceded by a breast carcinoma in situ. Breast carcinoma in situ patients had a 5-year net survival of 1.02 (95% CI: 1.01-1.03), whereas patients diagnosed with invasive breast cancer without a recorded breast carcinoma in situ had a 5-year net survival of 0.89 (95% CI: 0.88-0.90). Patients diagnosed first with breast carcinoma in situ and then with invasive breast cancer had a 5-year net survival of 0.92 (95% CI: 0.85-1.01).

CONCLUSION

Invasive breast tumours that were preceded by a breast carcinoma in situ were detected more frequently at an earlier stage, compared to those that were not. The estimated 5-year net survival of patients with breast tumours was good.

Oncological safety of active surveillance for low-risk ductal carcinoma in situ - a systematic review and meta-analysis

INTRODUCTION

Current standard of care for patients diagnosed with "low-risk" ductal carcinoma in situ (DCIS) involves surgical resection. Ongoing phase III clinical trials are hoping to establish the oncological safety of active surveillance (AS) in managing "low-risk" DCIS.

AIMS

To evaluate the oncological safety of AS versus surgery for "low-risk" DCIS.

METHODS

A systematic review was performed in accordance with PRISMA guidelines. Survival outcomes were expressed as dichotomous variables and reported as odds ratios (OR) with 95% confidence intervals (95% CI) using the Mantel-Haenszel method.

RESULTS

Four studies including 9626 patients were included, 3.9% of which were managed using AS (374/9626) and 96.1% with surgery (9252/9626). The mean age of included patients was 50.3 years (range: 30-99 years) and mean follow-up was 6.1 years. Invasive cancer detection after surgery and AS were similar (OR: 0.93, 95% CI: 0.41-2.11, P = 0.860, heterogeneity (I2) = 0%). At 5 years, BCSS (surgery 99.5% vs. AS 98.7%, P = 0.116) and OS (surgery 95.8% vs. AS 95.7%, P = 0.876) were similar for both groups. At 10 years, BCSS (surgery 98.7% vs. AS 98.6%, P = 0.789) and OS (surgery 87.9% vs. AS 90.9%, P = 0.183) were similar for both groups. Overall, 10-year OS outcomes were similar for both management strategies (OR: 0.32, 95% CI: 0.02-6.42, P = 0.460, I2 = 69%).

CONCLUSION

This study outlines the provisional oncological safety of AS for cases of "low-risk" DCIS. While survival outcomes were comparable for both management strategies, ratification of these results in the ongoing phase III clinical trials is still required prior to changes to current management strategies.

PROSPERO REGISTRATION

CRD42022313241.

Oncological outcomes after simple and skin-sparing mastectomy of ductal carcinoma in situ: A register-based cohort study of 576 Norwegian women

BACKGROUND

For Ductal Carcinoma in Situ (DCIS), recurrence is shown to be higher after skin-sparing (SSM) versus simple (SM) mastectomy. This study aimed to compare the two groups recurrence rates, disease-free survival (DFS), and overall (OS) survival.

METHODS

We conducted a retrospective register-based cohort study of women operated with SSM (n = 338) or SM (n = 238) for DCIS between 2007 and 2017. Data from the Norwegian Breast Cancer Registry was used to estimate recurrences rates, DFS and OS.

RESULTS

Mean age was 51 and 61 years in the SSM and SM groups, respectively. Median follow-up time was 77 months for SSM (range: 21-152 months) vs 84 months for SM (range: 7-171 months). After five years of follow-up, the overall recurrence rate (OR) was 2.1%; 3.9% for SSM and 0.9% for SM. After ten years, the rates were 3.0%, 6.2% for SSM and still 0.9% for SM. DFS was after ten years 92.2%; 91.8% for SSM, and 92.4% for SM. OS was 95.0%; 97.5% for SSM and 93.3% for SM at ten years. For SSM, involved margins represented a significant risk for recurrence.

CONCLUSION

The recurrence rate was higher in the SSM versus the SM group. Whether the difference is due to the operating procedures or underlying risk factors remains unknown. When stratifying for the difference in age, there was no statistical difference in DFS or OS. Involved margins in the SSM group were associated with an increased risk of recurrence.

Clinical value of contralateral breast cancers detected by pre-operative MRI in patients diagnosed with DCIS: a population-based cohort study

OBJECTIVES

For patients with ductal carcinoma in situ (DCIS), data about the impact of breast MRI at primary diagnosis on the incidence and characteristics of contralateral breast cancers are scarce.

METHODS

We selected all 8486 women diagnosed with primary DCIS in the Netherlands in 2011-2015 from the Netherlands Cancer Registry. The synchronous and metachronous detection of contralateral DCIS (cDCIS) and contralateral invasive breast cancer (cIBC) was assessed for patients who received an MRI upon diagnosis (MRI group) and for an age-matched control group without MRI.

RESULTS

Nineteen percent of patients received an MRI, of which 0.8% was diagnosed with synchronous cDCIS and 1.3% with synchronous cIBC not found by mammography. The 5-year cumulative incidence of synchronous plus metachronous cDCIS was higher for the MRI versus age-matched control group (2.0% versus 0.9%, p = 0.02) and similar for cIBC (3.5% versus 2.3%, p = 0.17). The increased incidence of cDCIS was observed in patients aged < 50 years (sHR = 4.22, 95% CI: 1.19-14.99), but not in patients aged 50-74 years (sHR = 0.89, 95% CI: 0.41-1.93).

CONCLUSIONS

MRI at primary DCIS diagnosis detected additional synchronous cDCIS and cIBC, and was associated with a higher rate of metachronous cDCIS without decreasing the rate of metachronous cIBC. This finding was most evident in younger patients.

KEY POINTS

• Magnetic resonance imaging at primary diagnosis of ductal carcinoma in situ detected an additional synchronous breast lesion in 2.1% of patients. • In patients aged younger than 50 years, the use of pre-operative MRI was associated with a fourfold increase in the incidence of a second contralateral DCIS without decreasing the incidence of metachronous invasive breast cancers up to 5 years after diagnosis. • In patients aged over 50 years, the use of pre-operative MRI did not result in a difference in the incidence of a second contralateral DCIS or metachronous invasive breast cancer.

Outcomes in patients with non‐invasive breast carcinoma

BACKGROUND AND AIM

Non-invasive breast carcinoma is considered to be localized disease and is distinguished from invasive ductal and lobular carcinomas. The local recurrence of non-invasive carcinoma after surgery may lead to development of invasive carcinoma and promote distant metastasis, which worsens the prognosis for breast cancer mortality. The distant metastasis of non-invasive carcinoma may involve the ductal microvasculature without invasion. The outcomes of non-invasive breast carcinoma were examined in this retrospective cohort study.

METHODS AND RESULTS

Of 872 primary breast cancers diagnosed at a single center between May 2008 and March 2022, 93 (10.6%) were found to be non-invasive carcinomas and were examined in this study. The breast cancer recurrence and survival rates of patients with non-invasive carcinoma were analyzed retrospectively. The median follow-up period was 1891 (range, 5-4804) days. All patients underwent surgical treatment [mastectomy with sentinel lymph node biopsy (SLNB) and partial mastectomy with or without SLNB, tumorectomy, and microdochectomy]. Postoperatively, radiation therapy was administered to 73 (78.4%) of the patients and endocrine therapy was administered to 64 (81.0%) of 79 patients with hormone-receptor positivity. Of 26 patients who underwent partial mastectomy with SLNB, 24 (92.3%) showed isolated tumor cells in the SLNs on one-step nucleic acid amplification. Local recurrence was observed in three (0.3%) patients; no distant metastasis was observed. One patient died of a noncancerous disease. The overall survival rate was 98.0% and the breast cancer-specific survival rate was 100.0%.

CONCLUSIONS

Non-invasive breast carcinoma, like invasive breast carcinoma, causes local recurrence, but has a good prognosis without distant metastasis. The clinical significance of isolated tumor cells in the SLNs as a systemic component of non-invasive breast carcinoma remains to be elucidated.

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.

Treatment of Ductal Carcinoma in situ: A Register-Based Study of Norwegian Women Diagnosed between 1995 and 2018

Introduction

The incidence of ductal carcinoma in situ (DCIS) has increased after implementation of mammographic screening. The lesion represents management challenges due to its undetermined growth pattern. We aimed to explore treatment of women aged 48-71 years diagnosed with DCIS between 1995 and 2018, by detection mode and histopathological characteristics.

Material and Methods

Data on surgical treatment and radiation therapy (RT) of 4,995 women diagnosed with DCIS were retrieved from the Cancer Registry of Norway. We described the percentage and frequency of breast-conserving treatment (BCT) for participants in BreastScreen Norway (screen-detected) and nonparticipants. We estimated the relative risk (RR) of BCT, using log-binomial regression models.

Results

Use of BCT increased from about 40% in 1995 to 85% in 2018. Use of BCT was more common among older than younger women and more commonly used for screen-detected versus tumors detected outside the screening program. Nine out of ten women with tumors ≤10 mm were treated with BCT and two out of ten with tumors >50 mm. RT was given to 89.3% of the women with tumors ≤10 mm, 34.1% of those with tumors classified as van Nuys' grade 1 and <10 mm and 96.0% of the tumors >50 mm. Use of BCT was less common for tumors >50 mm compared to <10 mm (RR adjusted for age, detection mode, van Nuys' grade, and localization: 0.26, 95% CI: 0.19-0.36).

Conclusion

BCT was increasingly used among women diagnosed with DCIS in Norway during the period from 1995 to 2018, particularly for screen-detected, small lesions with low van Nuys' grade.

Countercurrents: DCIS or Cancer? Why All the Confusion?

At present, women with ductal carcinoma in situ are counseled that they have a pre-malignant condition which carries the possibility of progression to a fully malignant breast cancer. However, in most cases, the treatment of DCIS resembles that of a small invasive breast cancer and this is a source of confusion to many. In order to properly evaluate the benefit of radiotherapy, mastectomy and contralateral mastectomy, it is necessary to consider the risks of ipsilateral invasive cancer and of contralateral breast cancer in women with DCIS and with small invasive breast cancer. Several registry-based studies indicate that the risks of ipsilateral and contralateral cancer are similar in the two conditions and therefore a similar approach to treatment is rational.

Comprehensive multiplexed immune profiling of the ductal carcinoma in situ immune microenvironment regarding subsequent ipsilateral invasive breast cancer risk

Background

Ductal carcinoma in situ (DCIS) is treated to prevent subsequent ipsilateral invasive breast cancer (iIBC). However, many DCIS lesions will never become invasive. To prevent overtreatment, we need to distinguish harmless from potentially hazardous DCIS. We investigated whether the immune microenvironment (IME) in DCIS correlates with transition to iIBC.

Methods

Patients were derived from a Dutch population-based cohort of 10,090 women with pure DCIS with a median follow-up time of 12 years. Density, composition and proximity to the closest DCIS cell of CD20⁺ B-cells, CD3⁺CD8⁺ T-cells, CD3⁺CD8⁻ T-cells, CD3⁺FOXP3⁺ regulatory T-cells, CD68⁺ cells, and CD8⁺Ki67⁺ T-cells was assessed with multiplex immunofluorescence (mIF) with digital whole-slide analysis and compared between primary DCIS lesions of 77 women with subsequent iIBC (cases) and 64 without (controls).

Results

Higher stromal density of analysed immune cell subsets was significantly associated with higher grade, ER negativity, HER-2 positivity, Ki67 ≥ 14%, periductal fibrosis and comedonecrosis (P < 0.05). Density, composition and proximity to the closest DCIS cell of all analysed immune cell subsets did not differ between cases and controls.

Conclusion

IME features analysed by mIF in 141 patients from a well-annotated cohort of pure DCIS with long-term follow-up are no predictors of subsequent iIBC, but do correlate with other factors (grade, ER, HER2 status, Ki-67) known to be associated with invasive recurrences.

Canine and feline in situ mammary carcinoma: A comparative review

Carcinoma in situ of the breast is a well-known entity in humans. In veterinary medicine, particularly in canine and feline mammary literature, there is no agreement whether the term in situ should be used to indicate a specific carcinoma histotype or the noninvasive status of a carcinoma of any histotype. Moreover, in the most recent histologic classification of mammary tumors published by the Davis-Thompson Foundation, it is suggested to abandon the term carcinoma in situ given the lack of standardized criteria defining this entity, replacing it with epitheliosis or ductal/lobular hyperplasia with severe atypia. This publication presents a critical review of the term in situ in human and veterinary medicine considering the evolution of the term over the years and its heterogeneous use by different authors, including variations in immunohistochemical markers for classification. This review aims to point out the lack of uniformity in the nomenclature and classification issues in veterinary medicine regarding the use of the term in situ, laying the ground for a process of standardization in future publications.

Multiple Metastases of the Liver and Lung After Breast-Conserving Surgery for Ductal Carcinoma In Situ Without Microinvasion of the Breast: A Case Report and Literature Review

Background

Ductal carcinoma in situ (DCIS) is a non-invasive disease that rarely causes distant metastasis. It is extremely rare for patients diagnosed with DCIS without microinvasion to develop distant metastasis in the absence of ipsilateral or contralateral breast recurrence. This is the first case report of multiple liver and lung metastases from DCIS after breast-conserving surgery and radiotherapy.

Case Presentation

A 45-year-old woman who was diagnosed with DCIS and received breast-conserving surgery, radiotherapy, and sequential endocrine therapy developed multiple metastases in the liver and lung despite not having bilateral breast recurrence at the 62-month follow-up. Comprehensive advanced breast cancer therapy was administered but did not prevent the progression of metastatic foci in the liver.

Conclusions

This case shows the poor potential outcome in DCIS. Further research should be conducted on metastasis in DCIS; reexamination and monitoring are indispensable for patients diagnosed with DCIS.

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

Simple Summary

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

Abstract

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

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.

Propensity for Early Metastatic Spread in Breast Cancer: Role of Tumor Vascularization Features and Tumor Immune Infiltrate

Breast cancer is a complex and highly heterogeneous disease consisting of various subtypes. It is classified into human epidermal growth receptor 2 (HER-2)-enriched, luminal A, luminal B and basal-like/triple negative (TNBC) breast cancer, based on histological and molecular features. At present, clinical decision-making in breast cancer is focused only on the assessment of tumor cells; nevertheless, it has been recognized that the tumor microenvironment (TME) plays a critical biologic role in breast cancer. This is constituted by a large group of immune and non-immune cells, but also by non-cellular components, such as several cytokines. TME is deeply involved in angiogenesis, immune-evasion strategies, and propensity for early metastatic spread, impacting on prognosis and prediction of response to specific treatments. In this review, we focused our attention on the early morphological changes of tumor microenvironment (tumor vasculature features, presence of immune and non-immune cells infiltrating the stroma, levels of cytokines) during breast cancer development. At the same time, we correlate these characteristics with early metastatic propensity (defined as synchronous metastasis or early recurrence) with particular attention to breast cancer subtypes.

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.

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.

Cardiovascular events and mortality in a population-based cohort initially diagnosed with ductal carcinoma in situ

Background

Ductal carcinoma in situ (DCIS) patients are usually diagnosed through cancer screening programs, suggesting a healthy user effect. In this population-based cohort, we assessed the risk of cardiovascular events and mortality in DCIS patients.

Methods

Using the Korean National Health Insurance Service database, 13,740 women, who were initially diagnosed with DCIS between 2007 and 2013, were analyzed. A control group was matched according to age and the year of diagnosis at a 3:1 ratio (n = 41,220). Follow-up was performed until 2016. Subgroup analysis was performed according to the subsequent diagnosis of invasive breast cancer within 1 year: pure DCIS and DCIS+Invasive group.

Results

DCIS patients were more likely to have underlying diseases, higher incomes, and to live in urban districts compared to the control group. Women diagnosed of DCIS had lower myocardial infarct risk (hazard ratio [HR] 0.64; 95% confidence interval [CI] 0.46–0.90) and lower stroke risk (HR 0.77; 95% CI 0.60–0.98) compared to the control group. This trend of lower risk was sustained after adjusting for age, income, residence and comorbidities. The mortality rate was similar between the control group and pure DCIS patients but was higher in the DCIS+Invasive group (HR 1.63; 95% CI 1.34–1.98). However, after adjusting for age, income, residence and comorbidities, mortality did not differ between the control group and DCIS+Invasive group (HR 0.99; 95% CI 0.78–1.24).

Conclusions

DCIS patients were at lower risk for MI and stroke compared to a control group despite a higher rate of comorbidities, which may reflect changes in health behaviour. The importance of managing pre-existing comorbidities along with DCIS treatment should be emphasized.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-08494-0.

Deep learning-based grading of ductal carcinoma in situ in breast histopathology images

Ductal carcinoma in situ (DCIS) is a non-invasive breast cancer that can progress into invasive ductal carcinoma (IDC). Studies suggest DCIS is often overtreated since a considerable part of DCIS lesions may never progress into IDC. Lower grade lesions have a lower progression speed and risk, possibly allowing treatment de-escalation. However, studies show significant inter-observer variation in DCIS grading. Automated image analysis may provide an objective solution to address high subjectivity of DCIS grading by pathologists. In this study, we developed and evaluated a deep learning-based DCIS grading system. The system was developed using the consensus DCIS grade of three expert observers on a dataset of 1186 DCIS lesions from 59 patients. The inter-observer agreement, measured by quadratic weighted Cohen's kappa, was used to evaluate the system and compare its performance to that of expert observers. We present an analysis of the lesion-level and patient-level inter-observer agreement on an independent test set of 1001 lesions from 50 patients. The deep learning system (dl) achieved on average slightly higher inter-observer agreement to the three observers (o1, o2 and o3) (κo1,dl = 0.81, κo2,dl = 0.53 and κo3,dl = 0.40) than the observers amongst each other (κo1,o2 = 0.58, κo1,o3 = 0.50 and κo2,o3 = 0.42) at the lesion-level. At the patient-level, the deep learning system achieved similar agreement to the observers (κo1,dl = 0.77, κo2,dl = 0.75 and κo3,dl = 0.70) as the observers amongst each other (κo1,o2 = 0.77, κo1,o3 = 0.75 and κo2,o3 = 0.72). The deep learning system better reflected the grading spectrum of DCIS than two of the observers. In conclusion, we developed a deep learning-based DCIS grading system that achieved a performance similar to expert observers. To the best of our knowledge, this is the first automated system for the grading of DCIS that could assist pathologists by providing robust and reproducible second opinions on DCIS grade.

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.

Patterns of treatment and outcome of ductal carcinoma in situ in the Netherlands

Purpose

To spare DCIS patients from overtreatment, treatment de-escalated over the years. This study evaluates the influence of these developments on the patterns of care in the treatment of DCIS with particular interest in the use of breast conserving surgery (BCS), radiotherapy following BCS and the use and type of axillary staging.

Methods

In this large population-based cohort study all women, aged 50–74 years diagnosed with DCIS from January 1989 until January 2019, were analyzed per two-year cohort.

Results

A total of 30,417 women were diagnosed with DCIS. The proportion of patients undergoing BCS increased from 47.7% in 1995–1996 to 72.7% in 2017–2018 (p < 0.001). Adjuvant radiotherapy following BCS increased from 28.9% (1995–1996) to 89.6% (2011–2012) and subsequently decreased to 74.9% (2017–2018; p < 0.001). Since its introduction, the use of sentinel lymph node biopsy (SLNB) increased to 63.1% in 2013–2014 and subsequently decreased to 52.8% in 2017–2018 (p < 0.001). Axillary surgery is already omitted in 55.8% of the patients undergoing BCS nowadays. The five-year invasive relapse-free survival (iRFS) for BCS with adjuvant radiotherapy in the period 1989–2010, was 98.7% [CI 98.4% – 99.0%], compared to 95.0% [CI 94.1% –95.8%] for BCS only (p < 0.001). In 2011–2018, this was 99.3% [CI 99.1% – 99.5%] and 98.8% [CI 98.2% – 99.4%] respectively (p = 0.01).

Conclusions

This study shows a shift toward less extensive treatment. DCIS is increasingly treated with BCS and less often followed by additional radiotherapy. The absence of radiotherapy still results in excellent iRFS. Axillary surgery is increasingly omitted in DCIS patients.

Association of a Diagnosis of Ductal Carcinoma In Situ With Death From Breast Cancer

IMPORTANCE

It is not clear to what extent a diagnosis of ductal carcinoma in situ (DCIS) impacts a woman's lifetime risk of dying of breast cancer. Under ideal circumstances, treatment will eliminate the risk of invasive ipsilateral recurrence and prevent subsequent mortality from breast cancer. The risk of dying of breast cancer after a diagnosis of DCIS had not been compared with that of women without cancer in the general population.

OBJECTIVE

To determine the risk of death from breast cancer in a large cohort of patients treated for DCIS and to compare the risk with that of women in the general population.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study included data for women who had first primary DCIS diagnosed between 1995 and 2014 from the Surveillance, Epidemiology and End Results (SEER) registries database. Women with DCIS underwent surgical treatment, and approximately half also received radiotherapy. These women were followed from the date of DCIS diagnosis until death from breast cancer or date of last follow-up. Women in the general population without breast cancer were analyzed as controls. Follow-up information was available up to December 2016. The data were analyzed in March 2020.

EXPOSURES

Patients with DCIS who underwent surgical treatment.

MAIN OUTCOMES AND MEASURES

Breast cancer death was the main outcome. Standardized mortality ratios were estimated by comparing deaths from breast cancer among women diagnosed with DCIS with expected deaths from breast cancer among women in the general population who did not have cancer. Expected probability of death from breast cancer in the general population was calculated by an incidence-based mortality approach using standardized SEER-based incidence and case-fatality rates. Probability of breast cancer death was estimated based on the assumption that a cancer-free control was cancer free on the date the woman with DCIS was diagnosed and was studied until the end of follow-up.

RESULTS

A total of 144 524 women diagnosed with first primary DCIS were included (mean [SD] age at diagnosis, 57.4 [11.0] years). There were 1540 deaths from breast cancer in the cohort. Based on SEER-based incidence and case-fatality rates, 458 breast cancer deaths were expected in an equivalent number of cancer-free women from the general population with equal follow-up. The standardized mortality ratio for death from breast cancer among women with DCIS was 3.36 (95% CI, 3.20-3.53). The elevated risk of death persisted more than 15 years after diagnosis.

CONCLUSIONS AND RELEVANCE

In the population studied, the risk of dying of breast cancer was increased 3-fold after a diagnosis of DCIS. This suggests that our current treatment focus on preventing invasive recurrence is insufficient to eliminate all deaths from breast cancer after DCIS.

Prognostic Score-Based Stratification Analysis Reveals Universal Benefits of Radiotherapy on Lowering the Risk of Ipsilateral Breast Event for Ductal Carcinoma In Situ Patients with Different Risk Levels

BACKGROUND

We aimed to analyze the effects of radiotherapy (RT) on the incidence rate of ipsilateral breast event (IBE) in ductal carcinoma in situ (DCIS) patients with lumpectomy after being stratified by prognostic score.

METHODS

We identified DCIS patients who received lumpectomy, from the Surveillance, Epidemiology, and End Results (SEER) database from 1988 to 2015. Cumulative incidence functions for competing risk were used to evaluate the effects of RT on IBE risk over time. Three multivariate regression models (weighted, non-weighted, and Fine-Gray) were applied to compare the IBE risk between the RT and non-RT groups after stratifying patients by prognostic score.

RESULTS

Overall, 72,623 DCIS patients were identified from the SEER database and 49,206 (66.8%) patients received RT. During the follow-up period (ranging from 7 to 347 months), the cumulative probability of invasive and in situ IBE was significantly lower in the RT group than in the non-RT group (p < 0.001). After being stratified by prognostic score, the weighted IBE incidence rate increased as the risk level increased (p < 0.050). In multivariate regression models, RT lowered the IBE incidence rate by at least 30% in low-, moderate-, and high-risk DCIS (p < 0.010). In particular, the in situ and invasive IBE incidence rate decreased by over 50% in low-risk DCIS with RT (p < 0.001).

CONCLUSIONS

RT is associated with a lowered IBE incidence rate in DCIS patients, regardless of the assigned risk levels for patients. The significant reduction in the IBE incidence rate in low-risk DCIS patients also indicates the potential benefits for recommending RT to such a patient population in clinical practice.

Other- and all-cause Mortality among women with breast cancer

BACKGROUND

Advances in early detection and treatment of breast cancer (BrCA) have led to better survival. Consequently, more women with BrCA now die from non-BrCA causes. We investigated all-cause and other-cause (non-BrCA) survival among women with BrCA.

METHODS

From the Prostate, Lung, Colorectal and Ovarian (PCLO) cohort, we selected women diagnosed with BrCA from 1994-2014. To compare survival of cases to non-cases, we used exposure density sampling. We computed standard mortality ratios (SMRs) and performed Cox proportional hazards models with matched case-control sets, controlling for demographics (Model I) and additional covariates (Model II). We also examined survival by stage within BrCA cases.

RESULTS

Among 78,215 women enrolled in PLCO, there were 1211 in-situ and 4790 invasive BrCA cases. 15-year survival rates were 97.1 % (BrCA-specific) and 77.2 % (other-cause) among in-situ and 86.4 % (BrCA-specific) and 73.4 % (other-cause) among invasive cases. For other-cause mortality, in-situ cases had lower risk in models I (HR = 0.74; 95 % CI:0.62-0.89) and II (HR = 0.75; 95 % CI:0.62-0.92) versus controls. All-cause mortality HRs for in-situ cases were 0.83 (95 % CI:0.70-0.99) and 0.85 (95 % CI:0.70-1.02) in Models I and II, respectively. Other-cause mortality was similar among invasive cases and controls. Within BrCA cases, higher stage was associated with increased other-cause mortality; HRs were 1.2 (95 % CI:1.1-1.5) and 1.7 (95 % CI:1.2-2.3) for stage II and III/IV versus stage I (Model II).

DISCUSSION

Mortality from other causes exceeded that of BrCA in both in-situ and invasive cases, highlighting the importance of managing patients' chronic conditions during and following cancer treatment.

The impact of patient characteristics and lifestyle factors on the risk of an ipsilateral event after a primary DCIS: A systematic review

Objective

The majority of ‘low-risk’ (grade I/II) Ductal Carcinoma In Situ (DCIS) may not progress to invasive breast cancer during a women’s lifetime. Therefore, the safety of active surveillance versus standard surgical treatment for DCIS is prospectively being evaluated in clinical trials. If proven safe and selectively implemented in clinical practice, a significant group of women with low-risk DCIS may forego surgery and radiotherapy in the future. Identification of modifiable and non-modifiable risk factors associated with prognosis after a primary DCIS would also enhance our care of women with low-risk DCIS.

Methods

To identify modifiable and non-modifiable risk factors for subsequent breast events after DCIS, we performed a systematic literature search in PUBMED, EMBASE and Scopus.

Results

Six out of the 3870 articles retrieved were included for final data extraction. These six studies included a total of 4950 patients with primary DCIS and 640 recorded subsequent breast events. There was moderate evidence for an association of a family history of breast cancer, premenopausal status, high BMI, and high breast density with a subsequent breast cancer or further DCIS.

Conclusion

There is a limited number of recent studies published on the impact of modifiable and non-modifiable risk factors on subsequent events after DCIS. The available evidence is insufficient to identify potential targets for risk reduction strategies, reflecting the relatively small numbers and the lack of long-term follow-up in DCIS, a low-event condition.

•

Need for risk management strategies for untreated DCIS patients.

•

Limited evidence for association between lifestyle factors and prognosis after DCIS.

•

Positive family history, premenopausal status, high breast density associated with prognosis.

Long-term risk of ischemic heart disease after adjuvant radiotherapy in breast cancer: results from a large population-based cohort

BACKGROUND

Adjuvant radiotherapy (RT) for breast cancer (BC) has been associated with an increased risk of ischemic heart disease (IHD). We examined the incidence of IHD in a large population-based cohort of women with BC.

METHODS

The Breast Cancer DataBase Sweden (BCBaSe) includes all women diagnosed with BC from 1992 to 2012 (n = 60,217) and age-matched women without a history of BC (n = 300,791) in three Swedish health care regions. Information on comorbidity, educational level, and incidence of IHD was obtained through linkage with population-based registries. The risk of IHD was estimated by Cox proportional hazard regression analyses and cumulative incidence by the Kaplan-Meier method.

RESULTS

Women with BC had a lower risk of IHD compared to women without BC with a hazard ratio (HR) of 0.91 (95% CI 0.88-0.95). When women with left-sided BC were compared to right-sided BC, an increased HR for IHD of 1.09 (95% CI 1.01-1.17) was seen. In women receiving RT, a HR of 1.18 (95% CI 1.06-1.31) was seen in left-sided compared to right-sided BC, and the HRs increased with more extensive lymph node involvement and with the addition of systemic therapy. The cumulative IHD incidence was increased in women receiving left-sided RT compared to right-sided RT, starting from the first years after RT and sustained with longer follow-up.

CONCLUSIONS

Women given RT for left-sided BC during 1992 to 2012 had an increased risk of IHD compared to women treated for right-sided BC. These women were treated in the era of three-dimensional conformal RT (3DCRT), and the results emphasize the importance of further developing and implementing RT techniques that lower the cardiac doses, without compromising the beneficial effects of RT.

[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.

Preoperative Delays in the Treatment of DCIS and the Associated Incidence of Invasive Breast Cancer

Background

Although treatment delays have been associated with survival impairment for invasive breast cancer, this has not been thoroughly investigated for ductal carcinoma in situ (DCIS). With trials underway to assess whether DCIS can remain unresected, this study was performed to determine whether longer times to surgery are associated with survival impairment or increased invasion.

Methods

A population-based study of prospectively collected national data derived from women with a clinical diagnosis of DCIS between 2004 and 2014 was conducted using the National Cancer Database. Overall survival (OS) and presence of invasion were assessed as functions of time by evaluating five intervals (≤ 30, 31–60, 61–90, 91–120, 121–365 days) between diagnosis and surgery. Subset analyses assessed those having pathologic DCIS versus invasive cancer on final pathology.

Results

Among 140,615 clinical DCIS patients, 123,947 had pathologic diagnosis of DCIS and 16,668 had invasive ductal carcinoma. For all patients, 5-year OS was 95.8% and unadjusted median delay from diagnosis to surgery was 38 days. With each delay interval increase, added relative risk of death was 7.4% (HR 1.07; 95% CI 1.05–1.10; P < 0.001). On final pathology, 5-year OS for noninvasive patients was 96.0% (95% CI 95.9–96.1%) versus 94.9% (95% CI 94.6–95.3%) for invasive patients. Increasing delay to surgery was an independent predictor of invasion (OR 1.13; 95% CI 1.11–1.15; P < 0.001).

Conclusions

Despite excellent OS for invasive and noninvasive cohorts, invasion was seen more frequently as delay increased. This suggests that DCIS trials evaluating nonoperative management, which represents infinite delay, require long term follow up to ensure outcomes are not compromised.

Electronic supplementary material

The online version of this article (10.1245/s10434-019-07844-4) contains supplementary material, which is available to authorized users.

Ductal carcinoma in situ: to treat or not to treat, that is the question

Ductal carcinoma in situ (DCIS) now represents 20-25% of all 'breast cancers' consequent upon detection by population-based breast cancer screening programmes. Currently, all DCIS lesions are treated, and treatment comprises either mastectomy or breast-conserving surgery supplemented with radiotherapy. However, most DCIS lesions remain indolent. Difficulty in discerning harmless lesions from potentially invasive ones can lead to overtreatment of this condition in many patients. To counter overtreatment and to transform clinical practice, a global, comprehensive and multidisciplinary collaboration is required. Here we review the incidence of DCIS, the perception of risk for developing invasive breast cancer, the current treatment options and the known molecular aspects of progression. Further research is needed to gain new insights for improved diagnosis and management of DCIS, and this is integrated in the PRECISION (PREvent ductal Carcinoma In Situ Invasive Overtreatment Now) initiative. This international effort will seek to determine which DCISs require treatment and prevent the consequences of overtreatment on the lives of many women affected by DCIS.

A retrospective alternative for active surveillance trials for ductal carcinoma in situ of the breast

Ductal carcinoma in situ (DCIS) of the breast is a nonobligate precursor of invasive breast cancer, accounting for 20 % of screen-detected breast cancers. Little is known about the natural progression of DCIS because most patients undergo surgery upon diagnosis. Many DCIS patients are likely being overtreated, as it is believed that only around 50 % of DCIS will progress to invasive carcinoma. Robust prognostic markers for progression to invasive carcinoma are lacking. In the past, studies have investigated women who developed a recurrence after breast-conserving surgery (BCS) and compared them with those who did not. However, where there is no recurrence, the patient has probably been adequately treated. The present narrative review advocates a new research strategy, wherein only those patients with a recurrence are studied. Approximately half of the recurrences are invasive cancers, and half are DCIS. So-called "recurrences" are probably most often the result of residual disease. The new approach allows us to ask: why did some residual DCIS evolve to invasive cancers and others not? This novel strategy compares the group of patients that developed in situ recurrence with the group of patients that developed invasive recurrence after BCS. The differences between these groups could then be used to develop a robust risk stratification tool. This tool should estimate the risk of synchronous and metachronous invasive carcinoma when DCIS is diagnosed in a biopsy. Identification of DCIS patients at low risk for developing invasive carcinoma will individualize future therapy and prevent overtreatment.

Comparison of Clinical and Pathologic Characteristics of Ductal Carcinoma in Situ Detected on Mammography versus Ultrasound Only in Asymptomatic Patients

The main purpose of this study was to retropectively compare the clinical and pathologic characteristics of ductal carcinoma in situ (DCIS) detected on mammography and ultrasound (US) in asymptomatic patients. From February 2014 to September 2016, 236 asymptomatic patients with primary pure DCIS and dense breasts were included. The patients were classified into two groups. The mammography group (n = 165) included patients with DCIS detected on mammography, and the US group (n = 71) included patients with DCIS detected on US only. Clinicopathologic characteristics were compared between the two groups. Subgroup analyses were performed with a cutoff age of 50 y and a cutoff tumor size of 20 mm. In 236 patients, younger age, smaller tumor size, low nuclear grade, no comedo necrosis and progesterone receptor positivity were observed more in the US group (p < 0.05). HER2 and Ki67 positivity was observed more frequently in the mammography group (p < 0.05). Similar results were obtained in 168 patients with DCIS <20 mm and in patients ≥50 y. In patients <50 y, smaller tumor size, low nuclear grade and no comedo necrosis were observed significantly more often in the US group. DCIS in the US group significantly more often manifested low nuclear grade, no comedo necrosis and hormone receptor positivity, whereas HER2 and Ki67 positivity was observed significantly more often in the mammography group.

Mortality of women with ductal carcinoma in situ of the breast: a population-based study from the Girona province, Spain (1994-2013)

PURPOSE

We aim to comprehensively describe the incidence and mortality trends of ductal carcinoma in situ (DCIS) in the Girona province, Spain (1994-2013) and to estimate the all-cause mortality excess risk of diagnosed women.

METHODS

Age-standardized rates of DCIS were estimated between 1994 and 2013. Standard mortality ratios (SMR) and absolute excess mortality were calculated overall and by tumor and patient characteristics. A sensitivity analysis was conducted excluding cases with a subsequent invasive breast cancer (sIBC).

RESULTS

Of the 641 women included, 56 died (follow-up time: 8.4 person-years). Between 1994 and 2013, a significant increase in incidence and decrease in mortality was identified among women aged between 50 and 69 years old. Neoplasms and circulatory system disease were the most common causes of death. No excess risk of death was found overall, except for women aged < 50 years (SMR = 3.44, 95% CI 1.85; 6.40) and those with a sIBC (SMR = 2.51, 95% CI 1.26; 5.02), risk that lessened when cases with sIBC were excluded. Patients with sIBC also showed an excess risk (SMR = 2.29, 95% CI 1.03; 5.10).

CONCLUSIONS

Among women aged 50-69 years old, incidence of DCIS has significantly increased yet mortality has decreased. Overall, the all-cause mortality risk of women diagnosed with DCIS remains similar to that of the general population except for women diagnosed before age 50 and those with sIBC, who showed a significant increased risk. Differential management of these patients should be considered.

Association of Radiotherapy With Survival in Women Treated for Ductal Carcinoma In Situ With Lumpectomy or Mastectomy

IMPORTANCE

Patients with ductal carcinoma in situ (DCIS) are treated with radiotherapy to reduce their risk of local invasive recurrence after breast-conserving surgery. However, the association of radiotherapy with breast cancer survival in patients with DCIS has not yet been clearly established.

OBJECTIVE

To determine the extent to which radiotherapy is associated with reduced risk of breast cancer mortality in a large cohort of patients treated for DCIS, using a propensity score-based matching approach.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study of women who had first primary DCIS diagnosed between 1998 and 2014 used data from the Surveillance, Epidemiology, and End Results 18 registries database. Information on age and year of diagnosis, ethnicity, income, tumor size, tumor grade, estrogen receptor status, all treatments (surgery and radiation), and outcomes (invasive local recurrence and death from breast cancer) was abstracted for 140 366 women diagnosed with first primary DCIS. Three separate comparisons were performed using 1:1 matching: lumpectomy with radiation vs lumpectomy alone; lumpectomy alone vs mastectomy; and lumpectomy with radiation vs mastectomy.

EXPOSURES

Use of radiotherapy and/or extent of surgery.

MAIN OUTCOMES AND MEASURES

Crude and adjusted 15-year breast cancer-specific mortality.

RESULTS

Of the 140 366 patients with DCIS in the cohort (109 712 [78.2%] white; mean [SD] age, 58.8 [12.3] years), 35 070 (25.0%) were treated with lumpectomy alone, 65 301 (46.5%) were treated with lumpectomy and radiotherapy, and 39 995 (28.5%) were treated with mastectomy. The actuarial 15-year breast cancer mortality rate was 2.33% for patients treated with lumpectomy alone, 1.74% for patients treated with lumpectomy and radiation, and 2.26% for patients treated with mastectomy. The adjusted hazard ratios for death were 0.77 (95% CI, 0.67-0.88) for lumpectomy and radiotherapy vs lumpectomy alone (29 465 propensity-matched pairs), 0.91 (95% CI, 0.78-1.05) for mastectomy alone vs lumpectomy alone (20 832 propensity-matched pairs), and 0.75 (95% CI, 0.65-0.87) for lumpectomy and radiotherapy vs mastectomy (29 865 propensity-matched pairs).

CONCLUSIONS AND RELEVANCE

In patients with DCIS, treatment with lumpectomy and radiotherapy was associated with a significant reduction in breast cancer mortality compared with either lumpectomy alone or mastectomy alone. This suggests that the survival benefit of radiation is likely not due to local control, but rather to systemic effects.

Breast cancer-related deaths according to grade in ductal carcinoma in situ: A Dutch population-based study on patients diagnosed between 1999 and 2012

BACKGROUND

The incidence of ductal carcinoma in situ (DCIS) has drastically increased over the past decades. Because DCIS is resected after diagnosis similar to invasive breast cancer, the natural cause and behaviour of DCIS is not well known. We aimed to determine breast cancer-specific survival (BCSS) and overall survival (OS) according to grade in DCIS patients after surgical treatment in the Netherlands.

PATIENTS AND METHODS

All DCIS patients diagnosed between 1999 and 2012 were selected from the Netherlands Cancer Registry. The cause of death was obtained from 'Statistics Netherlands'. BCSS and OS were estimated using multivariable Cox regression in the entire cohort and stratified for grades.

RESULTS

In total, 12,256 patients were included, of whom 1509 (12.3%) presented with grade I, 3675 (30.0%) with grade II, 6064 (49.5%) with grade III and 1008 (8.2%) with an unknown grade. During a median follow-up of 7.8 years, 1138 (9.3%) deaths were observed, and 179 (1.5%) were breast cancer-related. Of these, 10 patients had grade I; 46 grade II; 95 grade III and 28 an unknown grade. After adjustment for confounding, grade II and III were related to worse BCSS than grade I with hazard ratios of 1.92 (95% confidence interval [CI]: 0.97-3.81) and 2.14 (95% CI: 1.11-4.12), respectively. No association between grades and OS was observed.

CONCLUSION

BCSS and OS in DCIS patients were excellent. Because superior rates were observed for low-grade DCIS, it seems justified to investigate whether active surveillance may be a balanced alternative for conventional surgical treatment.

Ductal carcinoma in situ current trends, controversies, and review of literature

Ductal carcinoma in situ (DCIS) is a non-obligate precursor, non-invasive malignancy confined within the basement membrane of the breast ductal system. There is a wide variation in the natural history of DCIS with an estimated incidence of progression to invasive ductal carcinoma being at least 13%-50% over a range of 10 or more years after initial diagnosis. Regardless of the treatment strategy, long-term survival is excellent. The controversy surrounding DCIS relates to preventing under-treatment, while also avoiding unnecessary treatments. In this article, we review the incidence, presentation, management options and surveillance of DCIS. Furthermore, we address several current controversies related to the management of DCIS, including margin status, sentinel node biopsy, hormonal therapy, the role of radiation in breast conservation surgery, and various risk stratification schemes.

Risk of ischemic heart disease after radiotherapy for ductal carcinoma in situ

PURPOSE

The use of adjuvant radiotherapy (RT) in the management of ductal carcinoma in situ (DCIS) is increasing. Left-sided breast irradiation may involve exposure of the heart to ionising radiation, increasing the risk of ischemic heart disease (IHD). We examined the incidence of IHD in a population-based cohort of women with DCIS.

METHODS

The Breast Cancer DataBase Sweden (BCBase) cohort includes women registered with invasive and in situ breast cancers 1992-2012 and age-matched women without a history of breast cancer. In this analysis, 6270 women with DCIS and a comparison cohort of 31,257 women were included. Through linkage with population-based registers, data on comorbidity, socioeconomic status and incidence of IHD was obtained. Hazard ratios (HR) for IHD with 95% confidence intervals (CI) were analysed.

RESULTS

Median follow-up time was 8.8 years. The risk of IHD was not increased for women with DCIS versus women in the comparison cohort (HR 0.93; 95% CI 0.82-1.06), after treatment with radiotherapy versus surgery alone (HR 0.77; 95% CI 0.60-0.98) or when analysing RT by laterality (HR 0.85; 95% CI 0.53-1.37 for left-sided versus right-sided RT).

CONCLUSIONS

The risk of IHD was lower for women with DCIS allocated to RT compared to non-irradiated women and to the comparison cohort, probably due to patient selection. Comparison of RT by laterality did not show any over-risk for irradiation of the left breast.