The Demographic Features, Clinicopathological Characteristics and Cancer-specific Outcomes for Patients with Microinvasive Breast Cancer: A SEER Database Analysis

Characteristics and risk factors of axillary lymph node metastasis of microinvasive breast cancer

PURPOSE

To select patients who would benefit most from sentinel lymph node biopsy (SLNB) by investigating the characteristics and risk factors of axillary lymph node metastasis (ALNM) in microinvasive breast cancer (MIBC).

METHODS

This retrospective study included 1688 patients with MIBC who underwent breast surgery with axillary staging at the Asan Medical Center from 1995 to 2020.

RESULTS

Most patients underwent SLNB alone (83.5%). Seventy (4.1%) patients were node-positive, and the majority had positive lymph nodes < 10 mm, with micro-metastases occurring frequently (n = 37; 55%). Node-positive patients underwent total mastectomy and axillary lymph node dissection (ALND) more than breast-conserving surgery (BCS) and SLNB compared with node-negative patients (p < 0.001). In the multivariate analysis, independent predictors of ALNM included young age [odds ratio (OR) 0.959; 95% confidence interval (CI) 0.927-0.993; p = 0.019], ALND (OR 11.486; 95% CI 5.767-22.877; p < 0.001), number of lymph nodes harvested (≥ 5) (OR 3.184; 95% CI 1.555-6.522; p < 0.001), lymphovascular invasion (OR 6.831; 95% CI 2.386-19.557; p < 0.001), presence of multiple microinvasion foci (OR 2.771; 95% CI 1.329-5.779; p = 0.007), prominent lymph nodes in preoperative imaging (OR 2.675; 95% CI 1.362-5.253; p = 0.004), and hormone receptor positivity (OR 2.491; 95% CI 1.230-5.046; p = 0.011).

CONCLUSION

Low ALNM rate (4.1%) suggests that routine SLNB for patients with MIBC is unnecessary but can be valuable for patients with specific risk factors. Ongoing trials for omitting SLNB in early breast cancer, and further subanalyses focusing on rare populations with MIBC are necessary.

Racial disparities in disease-specific mortality and surgical management of patients with ductal carcinoma in situ with microinvasion

BACKGROUND AND OBJECTIVES

Given persistent racial disparities in breast cancer outcomes, this study explores racial differences in disease-specific mortality and surgical management among patients with microinvasive ductal carcinoma in situ (DCIS-MI).

METHODS

The Surveillance, Epidemiology, and End Results Program was queried for patients aged 18+ years with DCIS-MI between January 1, 2010 and December 31, 2018. The study cohort was divided into non-Hispanic Black (NHB) and non-Hispanic White (NHW) patients. Disease-specific mortality was evaluated using Cox proportional hazards models.

RESULTS

A total of 3400 patients were identified, of which 569 (16.7%) were NHB and 2831 (83.3%) were NHW. Compared with NHW patients, NHB patients had more positive lymph nodes (7.6% vs. 3.9% p < 0.001). In addition, NHB women were more likely to undergo axillary lymph node dissection (6.0% vs. 3.8%, p = 0.044) and receive chemotherapy (11.8% vs. 7.2%, p < 0.001). There were no racial differences in breast surgery type (p = 0.168), reconstructive surgery (p = 0.362), or radiation therapy (p = 0.342). Overall, NHB patients had worse disease-specific mortality (adjusted hazard ratio 2.13, 95% confidence interval [CI]: 1.10-4.14) with mortality risks diverging from NHW women after 3 years (6 years rate ratio [RR] 2.12, 95% CI: 1.13-4.34; 9 years RR 2.32, 95% CI: 1.24-4.35).

CONCLUSIONS

NHB women with DCIS-MI present with higher nodal disease burden and experience worse disease-specific mortality than NHW women.

Meta-analysis on axillary lymph node metastasis rate in ductal carcinoma in situ with microinvasion

OBJECTIVE

To address the question of axillary lymph node staging in ductal carcinoma in situ with microinvasion (DCIS-MI), we retrospectively evaluated axillary lymph nodes metastasis (ALNM) rate in a cohort of postsurgical DCIS-MI patients. By analyzing these data, we aimed to generate clinically relevant insights to inform treatment decision-making for this patient population.

METHODS

A systematic search was conducted on PubMed, Web of Science, Embase, The Cochrane Library, CNKI, Wanfang Database, Wipe, and China Biomedical Literature Database to identify relevant publications in any language. All the analyses were performed using Stata 16.0 software.

RESULTS

Among the 28 studies involving 8279 patients, the pooled analysis revealed an ALNM rate of 8% (95% CI, 7% to 10%) in patients with DCIS-MI. Furthermore, the rates of axillary lymph node macrometastasis, micrometastasis, and ITC in patients with DCIS-MI were 2% (95% CI, 2% to 3%), 3% (95% CI, 2% to 4%), and 2% (95% CI, 1% to 3%), respectively. Moreover, 13 studies investigated the non-sentinel lymph node (Non-SLN) metastasis rate, encompassing a total of 1236 DCIS-MI cases. The pooled analysis identified a Non-SLN metastasis rate of 33% (95% CI, 14% to 55%) in patients with DCIS-MI.

CONCLUSION

The SLNB for patients with DCIS-MI is justifiable and could provide a novel therapeutic basis for systemic treatment decisions.

An MRI-Based Radiomics Nomogram to Distinguish Ductal Carcinoma In Situ with Microinvasion From Ductal Carcinoma In Situ of Breast Cancer

RATIONALE AND OBJECTIVES

Accurate preoperative differentiation between ductal carcinoma in situ with microinvasion (DCISM) and ductal carcinoma in situ (DCIS) could facilitate treatment optimization and individualized risk assessment. The present study aims to build and validate a radiomics nomogram based on dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) that could distinguish DCISM from pure DCIS breast cancer.

MATERIALS AND METHODS

MR images of 140 patients obtained between March 2019 and November 2022 at our institution were included. Patients were randomly divided into a training (n = 97) and a test set (n = 43). Patients in both sets were further split into DCIS and DCISM subgroups. The independent clinical risk factors were selected by multivariate logistic regression to establish the clinical model. The optimal radiomics features were chosen by the least absolute shrinkage and selection operator, and a radiomics signature was built. The nomogram model was constructed by integrating the radiomics signature and independent risk factors. The discrimination efficacy of our nomogram was assessed by using calibration and decision curves.

RESULTS

Six features were selected to construct the radiomics signature for distinguishing DCISM from DCIS. The radiomics signature and nomogram model exhibited better calibration and validation performance in the training (AUC 0.815, 0.911, 95% confidence interval [CI], 0.703-0.926, 0.848-0.974) and test (AUC 0.830, 0.882, 95% CI, 0.672-0.989, 0.764-0.999) sets than in the clinical factor model (AUC 0.672, 0.717, 95% CI, 0.544-0.801, 0.527-0.907). The decision curve also demonstrated that the nomogram model exhibited good clinical utility.

CONCLUSION

The proposed noninvasive MRI-based radiomics nomogram model showed good performance in distinguishing DCISM from DCIS.

Prognostic Markers of Microinvasive Breast Carcinoma: A Systematic Review and Meta-Analysis

(1) Background: The prognostic factors of microinvasive (≤1 mm) breast carcinoma are not completely clear. The aim of this study was to perform a systematic review and meta-analysis to clarify these factors. (2) Methods: The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) methodology was followed. Two databases were interrogated, PubMed and Embase, and papers in English were included to address this question. The selected studies were those that reported on female patients affected by microinvasive carcinoma, and on prognostic factors with a hazard ratio (HR) for disease-free survival (DFS) and overall survival (OS). (3) Results: In total, 618 records were identified. After removing duplicates (166), identification, and screening (336 by title and abstract alone, 116 by full text and eventual supplementary material), 5 papers were selected. Seven different meta-analyses were conducted in this study, all referring to DFS, analyzing the following prognostic factors: estrogen receptor, progesterone receptor, HER2 status, multifocality and grade of microinvasion, patient's age, and lymph node status. Only lymph node status was associated with prognosis and DFS (total number of cases: 1528; Z = 1.94; p = 0.05). The other factors examined did not significantly affect prognosis (p > 0.05). (4) Conclusions: Positive lymph node status significantly worsens prognosis in patients with microinvasive breast carcinoma.

Ductal Carcinoma In Situ (DCIS) and Microinvasive DCIS: Role of Surgery in Early Diagnosis of Breast Cancer

Advances in treatments, screening, and awareness have led to continually decreasing breast cancer-related mortality rates in the past decades. This achievement is coupled with early breast cancer diagnosis. Ductal carcinoma in situ (DCIS) and microinvasive breast cancer have increasingly been diagnosed in the context of mammographic screening. Clinical management of DCIS is heterogenous, and the clinical significance of microinvasion in DCIS remains elusive, although microinvasive DCIS (DCIS-Mi) is distinct from "pure" DCIS. Upfront surgery has a fundamental role in the overall treatment of these breast diseases. The growing number of screen-detected DCIS diagnoses with clinicopathological features of low risk for local recurrence (LR) allows more conservative surgical options, followed by personalised adjuvant radiotherapy plans. Furthermore, studies are underway to evaluate the validity of surgery omission in selected low-risk categories. Nevertheless, the management, the priority of axillary surgical staging, and the prognosis of DCIS-Mi remain the subject of debate, demonstrating how the paucity of data still necessitates adequate studies to provide conclusive guidelines. The current scientific scenario for DCIS and DCIS-Mi surgical approach consists of highly controversial and diversified sources, which this narrative review will delineate and clarify.

Outcomes and imaging features of microinvasive carcinoma and ductal carcinoma in situ: Matched cohort study

INTRODUCTION

The purpose of this study is to investigate the differences in clinical outcomes between microinvasive carcinoma (mIC) and ductal carcinoma in situ (DCIS) and compare the imaging features of both using mammography, US and MRI.

MATERIALS AND METHODS

This retrospective study was approved by our institutional review board. Between January 2011 and December 2013, 516 women with mIC or DCIS confirmed by surgery were included. Patients were matched with propensity score matching to compare recurrence-free survival (RFS). RFS was compared using a Cox proportional hazards model. Imaging features were also compared between the two groups.

RESULTS

Among 516 women, 219 mIC and 297 DCIS tumors were identified. After matching, 132 women were allocated to each group. The mean follow-up duration was 80.2 months. In the matched cohort, no statistically significant association was observed between the DCIS and mIC groups in terms of total recurrence (hazard ratio [HR]: 1.7; 95% confidence interval [CI]: 0.8-4.0; P = 0.19), local-regional recurrence (HR: 3.4; 95% CI: 0.9-12.3, P = 0.07), or contralateral recurrence (HR: 0.9; 95% CI: 0.3-2.8, P = 0.89). Non-mass lesions at US (P = 0.004), moderate or marked background parenchymal enhancement (P = 0.04), and higher peak enhancement (P = 0.02) at MRI were more commonly seen in the mIC group than in the DCIS group.

CONCLUSION

Microinvasive carcinomas are distinct from DCIS in terms of imaging features, but no statistically significant association in recurrence survival.

Clinicopathological characteristics, treatments, and prognosis of breast ductal carcinoma in situ with microinvasion: A narrative review

Background

Ductal carcinoma in situ with microinvasion (DCIS-MI) is defined as ductal carcinoma in situ (DCIS) with a microscopic invasive focus ≤1 mm in the longest diameter. The current literature is controversial concerning the clinical prognostic features and management of DCIS-MI. This narrative review described recently reported literature regarding the characteristics, treatment, and prognosis of it.

Methods

Searching PubMed for relevant articles covering the period of 1982 to 2021 using the following terms by MeSH and free-word: breast cancer, microinvasion, DCIS, DCIS-MI, and invasive ductal carcinoma (IDC).

Results

DCIS-MI tends to express more aggressive pathological features such as necrosis, HER2+, ER- or PR-, and high nuclear grade. The overall prognosis of DCIS-MI is typically good, however, some indicators such as young age, HR-, HER2+ and multimicroinvasive lesions, were associated with worse prognoses. And there are also conflicting results on the differences between the prognoses of DCIS-MI and DCIS or T1a-IDC. Postoperative chemotherapy and anti-HER2 therapy still have uncertain benefits and are more likely to be used to treat high-risk patients who are HR- orHER2+ to improve the prognosis.

Conclusion

DCIS-MI has more aggressive pathological features, which may suggest its biological behavior is worse than that of DCIS and similar to early IDC. Although the overall prognosis of DCIS-MI is good, when making decisions about adjuvant therapy clinicians need to give priority to the hormone receptor status, HER2 expression and axillary lymph node status of patients, because these may affect the prognosis and treatment response.

Prognostic significance of microinvasion with ductal carcinoma in situ of the breast: a meta-analysis

PURPOSE

Ductal carcinoma in situ (DCIS) associated with invasive carcinoma ≤ 1 mm in size is defined as DCIS with microinvasion (DCIS/microinvasion) rather than as invasive breast carcinoma. The number of patients with microinvasion accounts for < 1% of all breast cancer in published studies. As the numbers are limited, the prognostic significance of DCIS/microinvasion has not been clearly elucidated. This meta-analysis aimed to investigate the survival differences between patients with DCIS/microinvasion and those with pure DCIS.

METHODS

A meta-analysis following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) methodology was performed. We searched three electronic databases (MEDLINE, Cochrane Library, and EMBASE) and included observational studies published in English that contained survival details of patients with either DCIS or DCIS/microinvasion.

RESULTS

This study identified 26 studies that described the clinicopathological characteristics of patients in both the DCIS and DCIS/microinvasion groups. Survival differences were evaluated in 10 of 26 studies. Disease-free survival and loco-regional recurrence-free survival were significantly shorter in patients with DCIS/microinvasion than in those with DCIS (Hazard ratio, 1.52; 95% confidence interval, 1.11-2.08; p = 0.01 and hazard ratio, 2.53; 95% confidence interval, 1.45-4.41; p = 0.001, respectively). Both overall survival and distant metastasis-free survival tended to be shorter in patients with DCIS/microinvasion than in patients with DCIS (Hazard ratio, 1.63; 95% CI, 0.63-4.23; p = 0.31 and hazard ratio, 1.85; 95% confidence interval, 0.74-4.66; p = 0.19, respectively) but the difference was not statistically significant.

CONCLUSION

Our meta-analysis suggests that DCIS/microinvasion may display more aggressive biological and clinical behavior than pure DCIS, highlighting the potential need for closer follow-up and consideration of adjuvant treatment strategies in DCIS patients with microinvasive disease.

Identifying recurrences and metastasis after ductal carcinoma in situ (DCIS) of the breast

Ductal carcinoma in situ (DCIS) of the breast is a non-invasive tumour that has the potential to progress to invasive ductal carcinoma (IDC). Thus, it represents a treatment dilemma: alone it does not present a risk to life, however, left untreated it may progress to a life-threatening condition. Current clinico-pathological features cannot accurately predict which patients with DCIS have invasive potential, and therefore clinicians are unable to quantify the risk of progression for an individual patient. This leads to many women being over-treated, while others may not receive sufficient treatment to prevent invasive recurrence. A better understanding of the molecular features of DCIS, both tumour-intrinsic and the microenvironment, could offer the ability to better predict which women need aggressive treatment, and which can avoid therapies carrying significant side-effects and such as radiotherapy. In this review, we summarise the current knowledge of DCIS, and consider future research directions.

Clinicopathological characteristics and prognosis of microinvasive breast cancer: A population-based analysis

OBJECTIVES

Microinvasive breast cancer (MIBC) is a special type of breast cancer with a relatively low prevalence, of which the understanding remains controversial. In this article, we aimed to clarify the clinicopathological characteristics and prognosis of MIBC in the setting of different molecular subtypes and give feasible suggestions on clinical practice in MIBC.

METHODS

This study utilized the data from Surveillance, Epidemiology, and End Results (SEER) database. Patients were divided into subgroups based on the molecular subtypes, of which the clinicopathological characteristics were further undergone comparative analyses. Kaplan-Meier method and Cox proportional hazard regression analysis were employed to determine the prognosis of the subtypes, and to explore the prognostic factors. Patients were randomly assigned in a 7:3 ratio to the training and validation cohorts. The independent risk variables were then adopted to generate a nomogram to predict the 3- and 5-year survival probability.

RESULTS

A total of 4301 MIBC patients between 2010 and 2016 were obtained from the SEER database, which were subsequently separated into HR+/HER2- (n = 2598), HR+/HER2+ (n = 723), HR-/HER2+ (n = 633), and HR-/HER2- (n = 347) groups. The HR+/HER2+ group showed the best overall survival (OS) (81.28 months, 95% CI 80.45-82.11) compared with other groups (p = 0.0089). The application of radiotherapy in HR+/HER2- and HR+/HER2+ MIBC patients brought out additional survival benefit compared with those without radiotherapy (p < 0.0001 and p = 0.024, respectively). The prognosis among four subgroups with or without chemotherapy showed no statistical difference. Based on the curated nomogram, the high-score group exhibited a better OS compared with patients from the low-score group.

CONCLUSIONS

Profound heterogeneity was detected among different molecular subtypes in MIBC patients, of which HR+/HER2+ subtype presented the best prognosis. For HR-positive MIBC patients, increasing survival benefits could be retrieved from radiotherapy. Chemotherapy was not recommended for patients with MIBC. Individual-based protocols were introduced based on the nomogram which warranted further validation.

Regional Lymph Node Metastasis and Axillary Surgery of Microinvasive Breast Cancer: A Population-Based Study

Microinvasive breast cancer (MBC for short) is a rare entity with the decision of axillary surgery under debate in clinical practice. We aimed to unravel the lymph node metastasis (LNM) rate, axillary surgery, and prognosis of MBC based on 11,692 patients derived from the Surveillance Epidemiology and End Results (SEER) database between 2003 and 2015. In this retrospective study, 19.5% (2276/11,692) of patients received axillary lymph node dissection (ALND), 80.5% (9416/11,692) received non-ALND. In the total cohort, 10-year breast cancer-specific survival (BCSS) was 96.3%, and the LNM rate was 6.4% (754/11,692). Multivariate analyses showed that LNM had the strongest predictive weight (N3, HR 14.200, 95% CI 7.933−25.417; N2, HR 12.945, 95% CI 7.725−21.694; N1, HR 3.05, 95% CI 2.246−4.140, all p < 0.001). Kaplan−Meier analyses showed that ALND did not confer a survival benefit on 10-year BCS in patients with N0 (94.7% vs. 97.1%, p < 0.001) and in patients with 1−2 positive nodes (92.1% vs. 89.5%, p = 0.355), respectively, when compared to non-ALND. Our study demonstrated that the vast majority of MBC have a low LNM rate and excellent prognosis; patients with LNM showed poor prognosis. Assessment of lymph node status is necessary, and non-ALND surgery is required and sufficient for MBC with 0−2 positive nodes.

National Cancer Institute Experience in Micro-invasive Breast Carcinoma Treatment and Outcome

AbstractBackground: Significant relationship between breast cancer immunophenotype and risk of recurrence either local and/or distant may help determine which patients might benefit more from axillary staging and whether axillary staging is warranted in all cases or not. Patients with microinvasive carcinoma can present with axillary LN. metastasis, with incidence ranges from 0% to 20% . Thus, sentinel node biopsies are considered for patients with microinvasive carcinoma. The role of axillary staging in MIBC is not well defined, with the rate of axillary L.N. metastases ranging 0–11 %. Current studies focus on the clinical characteristics of MIBC. However, only a few studies have evaluated the survival and treatment, especially adjuvant chemotherapy after surgery, for patients with MIBC.Methods: This is a retrospective study of 139 cases diagnosed with microinvasive breast carcinoma from 2011 to 2015 who were identified in the National Cancer Institute, Cairo University. The pathologic database of our hospital was searched to identify patients with a pathologic diagnosis of MIBC on surgical specimens. The clinical features, sonographic and mammographic images and pathology records were reviewed.Results: There is increased incidence of MIBC over the past decade. Patients with MIBC were managed surgically with BCS. MIBC have the good prognosis. However, patients who are negative hormonal receptors have relatively substantial risk of relapse within the first 5 years after surgical operation. Adjuvant chemotherapy can only improve the outcomes of patients with negative hormonal receptors. Further studies with prolonged follow-up of large cohort are warranted to assess the prognostic significance and treatment of this lesion.Keywords: MIBC, CIS, DCIS, BC

Low incidence of lymph node metastasis in patients with microinvasive breast cancer: a Korean nationwide study

Purpose

Microinvasive breast cancer (MIBC) is an invasive carcinoma with a tumor dimension not exceeding 1 mm. Owing to its low incidence, the rate of axillary node metastasis and its management are not well established. The aim of this study was to assess the incidence of lymph node metastasis (LNM) and identify variables associated with LNM, as well as to evaluate the need for axillary staging in MIBC patients by analyzing nationwide data.

Methods

The Korean Breast Cancer Society registry was searched to identify MIBC patients diagnosed between January 1996 and April 2020. Patients without neoadjuvant chemotherapy experiences, systemic metastasis, and missing or discordant data were eligible for the analysis. The incidence rate of LNM was determined, and variables associated with LNM were identified by multivariable regression analysis.

Results

Of 2,427 MIBC patients identified, 98 (4.0%) had LNM and 12 (0.5%) had N2/3 disease. Type of breast operation (odds ratio [OR], 2.093; 95% confidence interval [CI], 1.332–3.290; P = 0.001), age (OR, 2.091; 95% CI, 1.326–3.298; P = 0.002), hormone receptor status (OR, 2.220; 95% CI, 1.372–3.594; P = 0.001), and lymphovascular invasion (OR, 11.143; 95% CI, 6.354–19.540; P < 0.001) were significantly related to LNM.

Conclusion

The incidence of LNM in MIBC patients was only 4.0% in our study, suggesting that de-escalation of axillary surgical interventions could be carefully considered. The indications for axillary staging should be individualized considering tumor volume, age, hormone receptor status, and lymphovascular invasion to improve the quality of life of MIBC survivors.

Prognostic Factors and a Nomogram Predicting Survival in Patients with Breast Ductal Carcinoma in situ with Microinvasion: A Population-Based Study

Purpose

Ductal carcinoma in situ with microinvasion (DCISM) can be challenging to balance the risks of overtreatment versus undertreatment. We aim to identify prognostic factors in patients with DCISM and construct a nomogram to predict breast cancer-specific survival (BCSS).

Materials and Methods

A retrospective cohort study of women diagnosed with DCISM from 1988 to 2015 who were identified in the Surveillance, Epidemiology and End Results database. Clinical variables and tumor characteristics were evaluated, and Cox proportional-hazards regression was performed. A nomogram was constructed from the multivariate logistic regression to combine all the prognostic factors to predict the prognosis of DCISM patients at 5 years, 10 years, and 15 years.

Results

We identified 5438 total eligible breast cancer patients with a median and max survival time of 78 and 227 months, respectively. Here, patients with poorer survival outcomes were those diagnosed between 1988 and 2001, African-American race, under 40 years of age, higher tumor N stage, progesterone receptor-negative tumor, and received no surgery. The nomogram was constructed by the seven variables and passed the calibration and validation steps. The area under the receiver operating characteristic (ROC) curve (AUC) of both the training set and the validating set (5-year AUC: 0.77 and 0.88, 10-year AUC: 0.75 and 0.73, 15-year AUC: 0.72 and 0.65). Receiving chemotherapy was associated with a better BCSS (hazard ratio, HR=0.45, 95% confidence interval, 95% CI = 0.23–0.89), especially in patients with estrogen receptor (ER) negative, progesterone receptor (PR) negative (HR = 0.35, 95% CI = 0.13–0.97) and ER+PR-/ER-PR+ DCISM (HR = 0.07, 95% CI = 0.01–0.59).

Conclusion

Our current study is the first to construct nomograms of patients with DCISM which could help physicians identify breast cancer patients that more likely to benefit from more intensive treatment and follow-up. Chemotherapy might benefit patients with ER-PR- and ER+PR-/ER-PR+ DCISM.

The Role of Trastuzumab in Patients with HER2 Positive Small (pT1mi/a) Breast Cancers, a Multicenter Retrospective Study

Simple Summary

Treatment of small HER2+ breast cancers with adjuvant Trastuzumab is still controversial. This study aims to measure the effect of Trastuzumab in early stages of breast cancer (pT1mic/a pN0/1mi) in terms of disease recurrence and to identify which factors most affect the prognosis of small HER2+ tumors. We retrospectively selected and reviewed 100 HER2+ pT1mic-pT1a breast cancer patients with a median follow-up of 86 months. In our study the primary outcome was the disease recurrence rate, which appeared to be significantly lower among patients who received adjuvant Trastuzumab. Among the patients who did not receive adjuvant Trastuzumab, HR− HER2+ tumors showed a risk seven times higher of relapse. The results of our study indicate that adjuvant Trastuzumab reduces the risk of developing a disease recurrence even in small HER2+ tumors. Adjuvant targeted therapy should be considered in patients with HR− HER2+ tumors, the category with the highest risk of recurrence.

Abstract

The treatment with adjuvant Trastuzumab in patients diagnosed with HER2+ small breast cancers is controversial: limited prospective data from randomized trials is available. This study aims to measure the effect of Trastuzumab in the early stages of breast cancer (pT1mic/a pN0/1mi) in terms of disease recurrence and to identify which are the factors that most affect the prognosis of small HER2+ tumors. One hundred HER2+ pT1mic-pT1a breast cancer patients who were treated in three Turin Breast Units between January 1998 and December 2018 were retrospectively selected and reviewed. Trastuzumab was administered to 23 patients. Clinicopathological features and disease-free survival (DFS) were compared between different subgroups. The primary outcome was the disease recurrence rate. Median follow-up time was 86 months. Compared to pT1a tumors, pT1mic lesions had a higher tumor grade (84% of pT1mic vs. 55% of pT1a; p = 0.003), a higher Ki-67 index (81% vs. 46%; p = 0.007) and were more frequently hormone receptor (HR) negative (69% vs. 36%, p = 0.001). Disease recurrence rate was significantly lower among patients who received adjuvant Trastuzumab (p = 0.02), with this therapy conferring an 85% reduction in the risk of relapse (HR 0.15; p = 0.02). Among the patients who did not receive adjuvant Trastuzumab, the only factor significantly associated with an increased risk of developing a recurrence was the immunohistochemical (IHC) subtype: in fact, HR− HER2+ tumors showed a risk seven times higher of relapsing (HR 7.29; p = 0.003). Adjuvant Trastuzumab appears to reduce the risk of disease recurrence even in small HER2+ tumors. The adjuvant targeted therapy should be considered in patients with HR− HER2+ tumors since they have the highest risk of recurrence, independently from size and grade.

Characteristics, prognosis, risk factors, and management of recently diagnosed ductal carcinoma in situ with microinvasion

Background

Ductal carcinoma in situ with microinvasion (DCISM) represents ~1% of all breast cancer cases and is arguably a more aggressive subtype of ductal carcinoma in situ (DCIS). Lacking studies with a large population, the survival outcomes of DCISM are still poorly understood and the treatment recommendations remain controversial. This study aims to investigate the long‐term outcome of patients with DCISM, potential risk factors for their prognosis, and the difference of survival between patients treated with breast‐conserving surgery plus radiotherapy (BCT + RT) and mastectomy only.

Methods

In total, 1299 patients from 2008 to 2019 with DCISM were retrospectively retrieved. Clinicopathological features were analyzed. Subgroup analysis was conducted between patients who underwent BCT + RT and mastectomy only. Univariate and multivariate analyses were performed to identify prognostic factors for survival. Differences of survival between two groups were compared using the log‐rank test.

Results

Totally, 1286 patients had follow‐up information, the median follow‐up is 54.57 months, the 5‐year local–regional‐free survival (LRFS), distant metastasis‐free survival (DMFS), and overall survival (OS) were 98.6%, 97.1%, and 99.4%, respectively, two deaths were due to breast cancer. Multivariate analysis identified age <40 (p = 0.028) and close margin (≤2 mm) as independent negative prognostic factors for LRFS. No prognostic factors were identified for DMFS and OS. The 5‐year LRFS, DMFS, and OS of patients who had DCIS component ≥5 cm and underwent mastectomy without adjuvant radiotherapy were 100%, 98.4%, and 98.4%, respectively. After propensity score matching (PSM), no survival difference was observed between patients treated with BCT + RT or mastectomy only.

Conclusions

DCISM patients had a good survival, even those with DCIS component ≥5 cm. Patients aged <40 or with close margin (≤2 mm) had a poorer LRFS, but not DMFS or OS. BCT + RT is a feasible choice for DCISM patients.

Molecular alterations differentiate microinvasive carcinoma from ductal carcinoma in situ and invasive breast carcinoma: retrospective analysis of a large single-center series

Microinvasive carcinoma (MIC) of the breast is a rare lesion. The clinicopathologic features and biologic behavior of MIC are unclear. Whether MIC is a distinct entity or an interim stage in the progression from ductal carcinoma in situ (DCIS) to invasive breast carcinoma (IBC) remains to be determined. A retrospective review of clinicopathologic features and analysis of the expression of estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor 2 (HER-2), and Ki-67 in patients with MIC (90 cases), DCIS (268 cases) and IBC (1504 cases) was performed. Most MICs (93.3%) exhibited an intermediate to high nuclear grade, and this proportion was larger than that of DCIS (62.7%, P < 0.001) or IBC (85.4%, P = 0.036). The incidence of sentinel lymph node metastasis in MIC (12.5%) was higher than that of DCIS (1.6%, P < 0.001), but much lower than that of IBC (39.7%, P < 0.001). MICs had higher expression of HER-2 and lower expression of ER and PR compared to DCIS and IBC; and MIC was more likely to present with a HER-2+ subtype. Furthermore, DCIS exhibited greater HER-2 overexpression or gene amplification (P < 0.001) levels and lower proliferation index of Ki-67 (P < 0.001) compared to IBC. Our results suggest that the clinicopathologic and molecular phenotype of MIC are different from DCIS and IBC. Thus, MIC may be a distinct entity rather than an interim stage in the progression from DCIS to IBC. The prognosis of MIC and the biologic behavior of this uncommon subset need to be further explored.

Significance of HER2 in Microinvasive Breast Carcinoma

OBJECTIVES

We compared the clinicopathologic features, clinical management, and outcomes of human epidermal growth factor receptor 2 (HER2)-expressing and nonexpressing microinvasive breast carcinomas (MiBC) to explore the significance of HER2 in MiBC.

METHODS

Clinicopathologic and follow-up information of cases with final diagnosis of MiBC with known HER2 status between 2007 and 2019 were analyzed.

RESULTS

Nineteen (41.3%) HER2-positive (HER2+) and 27 (58.7%) HER2-negative (HER2-) MiBCs were identified. HER2 positivity was likely to be associated with high nuclear grade, presence of tumor-infiltrating lymphocytes, hormonal receptor negativity, and increased Ki-67 in both microinvasive and associated in situ carcinomas. Nodal metastases were found in 2 ER+/HER2- cases (5.3%). One HER2+ case was found to have isolated tumor cells in the axillary node. The majority of patients with HER2+ MiBCs (76.5%) did not receive HER2-targeted therapy. All patients with available follow-up were alive without recurrence or distant metastasis, with a median follow-up of 38 months.

CONCLUSIONS

Similar to the larger size of invasive breast carcinomas, HER2 positivity is associated with high-grade morphologic features in MiBCs. However, HER2 overexpression in MiBCs does not appear to be associated with nodal metastasis or worse outcome in our study cohort. The role of HER2-targeted therapy in this clinical setting merits additional study.

Breast ductal carcinoma in situ with micro-invasion versus ductal carcinoma in situ: a comparative analysis of clinicopathological and mammographic findings

AIM

To determine the differences in clinicopathological and mammographic findings between ductal carcinoma in situ (DCIS) and ductal carcinoma in situ with micro-invasion (DCIS-MI) and explore clinicopathological and mammographic factors associated with DCIS-MI.

MATERIALS AND METHODS

All DCIS patients with or without micro-invasion who underwent preoperative mammography at The Affiliated Hospital of Qingdao University from January 2016 through June 2020 were identified retrospectively. The correlations of clinicopathological findings with DCIS-MI were evaluated using univariate and multivariate binary logistic regression analyses. Imaging findings were compared between the groups by using the Pearson chi-square test.

RESULTS

A total of 445 DCIS lesions and 151 DCIS-MI lesions were included in the final analysis. Large extent (≥2.7 cm), high nuclear grade, comedo-type, negative progesterone receptor (PR), negative oestrogen receptor (ER), high Ki-67 and axillary lymph node metastasis were more frequently found in DCIS-MI than in DCIS (all p<0.05), and the first four of these were found to be independent predictors of DCIS-MI in the multivariate analysis (all p<0.05). Regarding imaging findings, compared to DCIS, DCIS-MI showed fewer occult lesions and more lesions with calcifications in mass, asymmetry, and architectural distortion (p=0.004). Grouped calcifications were usually associated with DCIS, while regional calcifications were commonly found in DCIS-MI (p<0.05).

CONCLUSION

Large extent, high nuclear grade, comedo-type and negative PR were found to be independent predictors of DCIS-MI. Lesions with calcifications and regional calcifications were more likely associated with DCIS-MI on mammography.

Axillary staging in ductal carcinoma in situ with microinvasion: A meta-analysis

INTRODUCTION

Ductal carcinoma in situ with microinvasion (DCISM); arguably a more aggressive subtype of DCIS, currently has variable recommendations governing its staging and management in the UK. As a result, there is ongoing controversy surrounding the most appropriate management of DCISM, in particular the need of axillary staging.

METHOD

A search was conducted on the databases MEDLINE and Embase using the keywords: breast, DCISM, microinvasion, "ductal carcinoma in situ with microinvasion", sentinel lymph node biopsy, SLNB, axillary staging was performed. 23 studies were selected for analysis. Primary outcome was the positivity of metastasis of lymph node; secondary outcome looked at characteristics of DCISM that may affect node positivity.

RESULTS

A total of 2959 patients were included. Significant heterogeneity was observed amongst the studies with regards to metastases (I² = 61%; P < 0.01). Lymph node macrometastases was estimated to be 2%. Significant subgroup difference was not observed between SLNB technique and lymph node macrometastases (Q = 0.74; p = 0.69). Statistical significance was observed between the focality of the DCISM and lymph node macrometastases (Q = 8.71; p = 0.033).

CONCLUSION

Although histologically more advanced than DCIS, DCISM is not linked with higher rates of clinically significant metastasis to axillary lymph nodes. Survival rates are very similar to those seen in cases of DCIS. Current evidence suggests that axillary staging in cases of DCISM will not change their overall management, thus may only be an unnecessary and inconvenient additional intervention considering the majority of DCISM diagnoses are made from post-operative pathology samples. A multidisciplinary team approach evaluating pre-operative clinical and histological information to tailor the management specific to individual cases of DCISM would be a preferred approach than routine axillary staging.

Multiple Microinvasion Foci in Ductal Carcinoma In Situ Is Associated With an Increased Risk of Recurrence and Worse Survival Outcome

Background

Ductal carcinoma in situ with microinvasion (DCISM) was defined as one or more foci of invasion beyond the basement membrane within 1 mm. The size of primary lesion is associated with axillary status and prognosis in patients with invasive breast cancer; thus, it is of interest to determine whether multiple foci of microinvasion are associated with a higher risk of positive axillary status or worse long-term outcomes in patients with DCISM.

Methods

This study identified 359 patients with DCISM who had undergone axillary evaluation at our institute from January 2006 to December 2015. Patients were categorized as one focus or multiple foci (≥2 foci) according to the pathological results. Clinicopathological features, axillary status, and disease-free survival rate were obtained and analyzed.

Results

Of 359 patients, 233 (64.90%) had one focus of microinvasion and 126 (35.10%) had multiple foci. Overall, 242 (67.41%) and 117 (32.59%) patients underwent sentinel lymph nodes biopsy (SLNB) and axillary lymph nodes dissection (ALND), respectively. Isolated tumor cells were found in four (1.11%) patients and axillary metastasis rate was 2.51%. Neither axillary evaluation methods (P = 0.244) nor axillary metastasis rate (P = 0.559) was significantly different between patients with one focus and multiple foci. In univariate analysis, patients with multiple foci tended to have larger tumor size (P < 0.001), higher nuclear grade (P = 0.001), and higher rate of lymphatic vascular invasion (P = 0.034). Also, the proportion of positive HER2 (P = 0.027) and Ki67 level (P = 0.004) increased in patients with multiple foci, while in multivariate analysis, only tumor size showed significant difference (P = 0.009). Patients with multiple foci were more likely to receive chemotherapy (56.35 vs 40.77%; P = 0.028). At median 5.11 years follow-up, overall survival rate was 99.36%. Patients with multiple microinvasive foci had worse disease-free survival rate compared with one-focus patients (98.29 vs 93.01%, P = 0.032).

Conclusion

Even though the numbers of microinvasion were different and patients with multiple foci of microinvasion tended to have larger tumor size, there was no higher risk of axillary involvement compared with patients with one focus of microinvasion, while patients with multiple microinvasive foci had worse DFS rate. Thus, DCISM patients with multiple foci of microinvasion may be the criterion for more aggressive local–regional treatment. Optimization of adjuvant therapy in DCISM patients is required.

Breast Microinvasive Carcinoma With Different Morphologies: Analysis of Clinicopathologic Features of 121 Cases

Purpose:

To investigate the clinicopathological features of patients with breast microinvasive carcinoma (MI).

Methods:

The clinical data of 121 cases with breast MI were retrospectively collected. The whole tumor in each case was stained with hematoxylin and eosin (H&E) for pathological evaluation. The relationships among size of tumor, histological grade, tumor-infiltrating lymphocytes (TILs), the number of MIs, type of MI, and lymph node metastasis were analyzed.

Results:

It was revealed that 86% of the cases had high-grade ductal carcinoma in situ (DCIS) and 63.6% had multiple MIs. The larger size of the tumors, the higher the grade of DCIS, the more the number of MIs; 3.3% of cases had rich TILs (lymphocyte/stroma > 30%) in the DCIS, and 26.5% had rich TILs in MIs. The type A of MIs is characterized by single cells and small clusters of solid cells. Tumor cells in type B of MIs can form glandular ducts. Formal grading of microinvasive is challenging/impossible due to its limited size precluding a representative mitotic count. But nuclear grade and tubule (differentiation) grades can be reported. In addition, 72.7% of cases had type A of MIs and 27.3% of cases had type B of MIs. Type B was found to be highly accompanied by moderate-grade DCIS. Only 6.6% of patients with MI had lymph node metastasis, which was mainly related to MIs with less TILs.

Conclusion:

Breast MI is easy to occur in high-grade DCIS, and multiple infiltration foci may be observed in case with tumor size of higher than 3.5 cm. Microinvasive carcinoma with poor TILs maybe a risk factor for lymph node metastasis in patient with DCIS-Mi.

Characteristics of Microinvasive Ductal Carcinoma In Situ Versus Noninvasive and Invasive Breast Cancer

BACKGROUND

The present literature is conflicting regarding the management of microinvasive ductal carcinoma in situ (miDCIS) as to following recommendations for DCIS (margin status, surgical axillary staging, and possible observation) versus invasive breast cancer. We hypothesize that miDCIS represents more aggressive disease than pure DCIS.

METHODS

We performed a retrospective review of female miDCIS patients compared with age-matched cohorts of DCIS and T1b/c patients with invasive breast cancer. We collected demographic, clinicopathologic, treatment, and outcome information. Analysis of variance or Kruskal-Wallis tests were used to analyze continuous variables and chi-square or Fisher's exact tests for categorical variables. Survival outcomes were analyzed using Kaplan-Meier curves.

RESULTS

We included 375 patients (125 in each group) with median age 59 y (range 33-91 y). miDCIS tumors were more likely to be hormone receptor negative and human epidermal growth factor receptor 2 positive compared with DCIS or invasive ductal carcinoma (IDC; all P < 0.001). Subgroup analysis by miDCIS focality demonstrated no significant differences. The number of involved lymph nodes was not significantly different from DCIS patients but was significantly fewer than invasive cancer patients. Of 115 miDCIS patients (88%) staged with sentinel lymph node biopsy, eight (7%) had nodal metastases. Six miDCIS patients (5%) were treated with adjuvant chemotherapy. Over a median follow-up of 23.3 mo, there were no significant differences in local or distant recurrence.

CONCLUSIONS

Based on our results, miDCIS has more aggressive pathologic features compared with DCIS and warrants surgical treatment and nodal staging similar to the management of IDC. In addition, similar to IDC, nodal and receptor status may influence medical management.

A Nomogram to Predict Factors Associated with Lymph Node Metastasis in Ductal Carcinoma In Situ with Microinvasion

INTRODUCTION

Ductal carcinoma in situ (DCIS) with foci of invasion measuring ≤ 1 mm (DCISM), represents < 1% of all invasive breast cancers. Sentinel lymph node biopsy (SLNB) has been a standard component of surgery for patients with invasive carcinoma or extensive DCIS. We hypothesize that selective performance of SLNB may be appropriate given the low incidence of sentinel node (SN) metastasis for DCISM. We investigated the clinicopathologic predictors for SN positivity in DCISM, to identify which patients might benefit from SLNB.

METHODS

A retrospective review of the National Cancer Database was performed for cases from 2012 to 2015. Clinical and tumor characteristics, including SN results, were evaluated, and Pearson's Chi square tests and logistic regression were performed.

RESULTS

Of 7803 patients with DCISM, 306 (4%) had at least one positive SN. Patients with positive SNs were younger, more often of Black race, had higher-grade histology and larger tumor size, and were more likely to have lymphovascular invasion (LVI; all p < 0.001). In an adjusted model, the presence of LVI was associated with the highest odds ratio (OR) for node positivity (OR 8.80, 95% confidence interval 4.56-16.96).

CONCLUSIONS

Among women with DCISM, only 4% had a positive SN. Node positivity was associated with more extensive and higher-grade DCIS, and the presence of LVI was strongly correlated with node positivity. Our data suggest that LVI is the most important factor in determining which patients with DCISM will benefit from SN biopsy.

Repression of miR-135b-5p promotes metastasis of early-stage breast cancer by regulating downstream target SDCBP

Metastasis is an essential event for breast cancer (BC) progression even after initial surgery. The identification of patients with a high probability of metastasis at an early stage is particularly important in clinical practice and requires individualized treatment or early prevention. A retrospective study of 242 cases of ductal carcinoma in situ with microinvasion (DCIS-Mi), the first stage of invasive BC, was performed in this follow-up analysis. Of all patients, 8 developed metastases, and they were all included for further mechanistic studies with control group of 24 DCIS-Mi by matched-pair designing. By screening DCIS-Mi with different prognoses, we found that the DCIS-Mi that metastasized had significantly lower miR-135b-5p expression than the DCIS-Mi that did not. The function of miR-135b-5p was studied in vitro and in vivo invasion and metastasis assays. We also validated a novel target gene for miR-135b-5p, syndecan binding protein (SDCBP), and assessed the functional consequences of SDCBP by invasion assays. By checking different BC cell lines, a strong inverse correlation between miR-135b-5p and SDCBP expression was recorded. For the functional study, the inhibition of miR-135b-5p was accompanied by increased BC cell growth, epithelial-mesenchymal transition (EMT), migration and invasion in vitro. Interestingly, silencing SDCBP can reverse miR-135b-5p-dependent EMT and proliferation. In vivo studies demonstrated that the newly revealed miR-135b-5p/SDCBP axis increased cell proliferation, invasion and malignant transformation, as well as promoted metastasis in a xenograft tumor mouse model. Thus, our clinical patient cohort and functional data suggest that miR-135b-5p/SDCBP is a crucial determinant of BC metastasis at a very early stage. Our results may shed light on the importance of miR-135b-5p molecular diagnosis and prognosis, as well as the early prevention of BC for metastasis.

DCIS with Microinvasion: Is It In Situ or Invasive Disease?

BACKGROUND

Ductal carcinoma in situ (DCIS) with microinvasion (DCISM) can be challenging in balancing the risks of overtreatment versus undertreatment. We compared DCISM, pure DCIS, and small volume (T1a) invasive ductal carcinoma (IDC) as related to histopathology, treatment patterns, and survival outcomes.

METHODS

Women ages 18-90 years who underwent breast surgery for DCIS, DCISM, or T1a IDC were selected from the SEER Database (2004-2015). Multivariate logistic regression and Cox proportional hazards models were used to estimate the association of diagnosis with treatment and survival, respectively.

RESULTS

A total of 134,569 women were identified: 3.2% DCISM, 70.9% DCIS, and 25.9% with T1a IDC. Compared with invasive disease, DCISM was less likely to be ER+ or PR+ and more likely to be HER2+. After adjustment, DCIS and invasive patients were less likely to undergo mastectomy than DCISM patients (DCIS: OR 0.53, 95% CI 0.49-0.56; invasive: OR 0.86, CI 0.81-0.92). For those undergoing lumpectomy, the likelihood of receiving radiation was similar for DCISM and invasive patients but lower for DCIS patients (OR 0.57, CI 0.52-0.63). After adjustment, breast-cancer-specific survival was significantly different between DCISM and the other two groups (DCIS: HR 0.59, CI 0.43-0.8; invasive: HR 1.43, CI 1.04-1.96). However, overall survival was not significantly different between DCISM and invasive disease, whereas patients with DCIS had improved OS (HR 0.83, CI 0.75-0.93).

CONCLUSIONS

Although DCISM is a distinct entity, current treatment patterns and prognosis are comparable to those with small volume IDC. These findings may help providers counsel patients and determine appropriate treatment plans.

Multiple foci of microinvasion is associated with an increased risk of invasive local recurrence in women with ductal carcinoma in situ treated with breast-conserving surgery

PURPOSE

The impact of Ductal Carcinoma in Situ (DCIS) with multiple foci of microinvasion (MI) (≤ 1 mm) on the risks of local recurrence (LR) and invasive LR is unknown, leading to uncertainty if DCIS with multiple foci of MI requires more aggressive treatment. We report a population-based analysis of the impact of multiple foci of MI, confirmed by pathology review, on the 15-year risks of LR and invasive LR treated with breast-conserving surgery (BCS) ± radiotherapy (RT).

METHODS

Cohort includes all women diagnosed with DCIS ± MI from 1994 to 2003 treated with BCS ± RT. Cox proportional hazards model was used to evaluate the impact of multiple foci of MI on the risks of LR and invasive LR, adjusting for covariates. The 15-year local and invasive local recurrence-free survival rates were calculated using the Kaplan-Meier method with differences compared by log-rank test.

RESULTS

The cohort includes 2988 women treated by BCS; 2721 had pure DCIS (51% received RT), 267 had DCIS with one or more foci of MI (58% had RT). Median follow-up was 13 years. Median age at diagnosis was 58 years. On multivariable analyses, the presence of multiple foci of MI was associated with an increased risk of invasive LR (HR = 1.59, 95% CI 1.01-2.49, p = 0.04) but not DCIS LR (HR = 0.89, 95% CI 0.46, 1.76, p = 0.7). The 15-year invasive LRFS risks for cases with pure DCIS, with 1 focus or multiple foci of MI were 85.7%, 85.6%, 74.7% following treatment by BCS alone, 87.2%, 89.9%, and 77% for those treated with BCS + RT without boost and 89.2%, 91.3%, and 95% for women treated with BCS + RT and boost.

CONCLUSIONS

The presence of multiple foci of MI in DCIS is associated with higher 15-year risks of invasive LR after breast-conserving therapy compared to women with pure DCIS but treatment with whole breast and boost RT can mitigate this risk.

Imaging features that distinguish pure ductal carcinoma in situ (DCIS) from DCIS with microinvasion

Patients with ductal carcinoma in situ with microinvasion (DCISM) have worse cancer-specific survival, disease-free survival and overall survival, and a higher mortality rate compared with patients with ductal carcinoma in situ (DCIS). Distinguishing DCISM from DCIS via preoperative imaging could help to predict the prognosis of patients. The present study compared the sonographic and mammographic features of patients with DCIS and DCISM. A total of 147 women (94 patients with DCIS and 53 patients with DCISM) were retrospectively included. The sonographic lesions were classified as either masses or non-mass abnormalities. The lesions observed on mammography were classified as calcifications only, mass, asymmetry or architectural distortion. Statistical comparisons were performed using the Mann-Whitney U test, χ² test, Fisher's exact test and multiple logistic regression analysis. Univariate and multivariate analyses showed that the presence of calcifications (P=0.038) and vascularity (P=0.025) on sonography were associated with DCISM. Furthermore, a lager distribution of calcifications was associated with a higher likelihood of DCISM (P=0.002). In conclusion, the presence of calcifications and vascularity on sonography or a lager distribution of calcifications on mammography may suggest DCISM.

Is Sentinel Lymph Node Biopsy Required for a Core Biopsy Diagnosis of Ductal Carcinoma In Situ with Microinvasion?

BACKGROUND

Among patients with a core biopsy diagnosis of ductal carcinoma in situ (DCIS), approximately 10% have microinvasion (DCISM), which, like DCIS, is subject to upstaging by surgical excision, but for which the rates of T and N upstaging are unknown, as is the role of sentinel lymph node biopsy (SLNB), since current studies of SLNB for DCISM are based on the final pathologic report, not the core needle biopsy. In this study, we identified the rates of T and N upstaging following surgical excision in patients with a suspected versus definite core needle biopsy diagnosis of DCISM.

METHODS

Overall, 369 consecutive patients (2007-2017) with a core biopsy diagnosis of suspected versus definite DCISM and surgical excision were stratified by extent of DCISM on core biopsy: suspicious focus, single focus, multiple foci/single biopsy, and multiple foci/multiple biopsies. Within strata, we identified clinicopathologic features associated with T and N upstaging.

RESULTS

Across core biopsy strata, there were no clear differences in imaging characteristics or median invasive tumor size (0.2 cm). Among 105 patients with a core biopsy suspicious for DCISM versus 264 with definite DCISM, 28% and 37%, respectively, were upstaged to at least pT1a, but only 1% and 6%, respectively, to pN1.

CONCLUSIONS

Although 28% of patients with suspected DCISM on core biopsy were surgically upstaged to invasive cancer, the frequency of pN1 SLN metastasis (1%) was comparable with that of DCIS, and was insufficient to recommend SLNB at initial surgery. SLNB remains reasonable for patients with definite DCISM on core biopsy.

Sentinel lymph node biopsy in microinvasive ductal carcinoma in situ

BACKGROUND

Microinvasive breast cancer is an uncommon pathological entity. Owing to the rarity of this condition, its surgical axillary management and overall prognosis remain controversial.

METHODS

A database was analysed to identify patients with microinvasive ductal carcinoma in situ (DCIS) who had surgery for invasive breast cancer at the European Institute of Oncology, Milan, between 1998 and 2010. Women who had undergone axillary staging by sentinel lymph node biopsy were included in the study.

RESULTS

Of 257 women with microinvasive breast cancer who underwent sentinel lymph node biopsy (SLNB), 226 (87·9 per cent) had negative sentinel lymph nodes (SLNs) and 31 had metastatic SLNs. Twelve patients had isolated tumour cells (ITCs), 14 had micrometastases and five had macrometastases in sentinel nodes. Axillary lymph node dissection was performed in 16 of the 31 patients with positive SLNs. After a median follow-up of 11 years, only one regional first event was observed in the 15 patients with positive SLNs who did not undergo axillary lymph node dissection. There were no regional first events in the 16 patients with positive SLNs who had axillary dissection.

CONCLUSION

Good disease-free and overall survival were found in women with positive SLNs and microinvasive DCIS. This study is in line with studies showing that SLNB in microinvasive DCIS may not be useful, and supports the evidence that less surgery can provide the same level of overall survival with better quality of life.

Sentinel lymph node biopsy in patients affected by breast ductal carcinoma in situ with and without microinvasion: Retrospective observational study

With the introduction of an organized mammographic screening, the incidence of ductal carcinoma in situ (DCIS) has experienced an important increase. Our experience with sentinel lymph node biopsy (SLNB) among patients with DCIS is reviewed.We collected retrospective data on patients operated on their breasts for DCIS (pTis), DCIS with microinvasion (DCISM) (pT1mi) and invasive ductal carcinoma (IDC) sized ≤2 cm (pT1) between January 2002 and June 2016, focusing on the result of SLNB.543 DCIS, 84 DCISM, and 2111 IDC were included. In cases of DCIS and DCISM, SLNB resulted micrometastatic respectively in 1.7% and 6.0% of cases and macrometastatic respectively in 0.9% and 3.6% of cases. 5-year disease-free survival and overall survival in DCISM and IDC were similar, while significantly longer in DCIS. 5-year local recurrence rate of DCIS and DCISM were respectively 2.5% and 7.9%, and their 5-year distant recurrence rate respectively 0% and 4%. IDC, tumor grading ≥2 and lymph node (LN) macrometastasis were significant predictors for decreased overall survival. Significant predictors for distant metastases were DCISM, IDC, macroscopic nodal metastasis, and tumor grading ≥2. Predictors for the microinvasive component in DCIS were tumor multifocality/multicentricity, grading ≥2, ITCs and micrometastases.Our study suggests that despite its rarity, sentinel node metastasis may also occur in case of DCIS, which in most cases are micrometastases. Even in the absence of an evident invasive component, microinvasion should always be suspected in these cases, and their management should be the same as for IDC.

Predicting underestimation of ductal carcinoma in situ: a comparison between radiomics and conventional approaches

PURPOSE

We aimed to investigate the feasibility of predicting invasion carcinoma from ductal carcinoma in situ (DCIS) lesions diagnosed by preoperative core needle biopsy using radiomics signatures, clinical imaging characteristics, and breast imaging reporting and data system (BI-RADS) descriptors on mammography.

METHODS

Retrospectively, we enrolled 362 DCIS patients diagnosed by core needle biopsy, 110 (30.4%) of which had invasive carcinoma confirmed by operation and pathology. We analyzed the images identified suspicious calcification from 250 subjects (161 pure DCIS and 89 DCIS with invasion). A total of 569 calcification radiomics signatures were extracted from microcalcification for each patient. We included a group of routine clinical imaging characteristics and BI-RADS descriptors for comparison purpose. Five feature selection and seven classification methods were evaluated in terms of their prediction performance. We compared the area under the receiver operating characteristic curve (AUC) averaged from tenfold cross-validation of different feature sets to identify the best combination of feature selection and classification methods.

RESULTS

Optimal feature selection and classification methods were identified after evaluating various combinations of feature sets. The best performance was achieved using both radiomics and clinical imaging characteristics (AUC = 0.72) performing better than BI-RADS descriptors or radiomics, but was no significant difference with clinical imaging characteristics (AUC = 0.66). The most significant features found were morphology signatures, first-order statistics, asymmetry/mass prevalence, and nuclear grade.

CONCLUSIONS

We found that the prediction model established using microcalcifications radiomics signatures and clinical imaging characteristics has the potential to identify an understaging of invasive breast cancer.

Risk factors for lymph node metastasis and the impact of adjuvant chemotherapy on ductal carcinoma in situ with microinvasion: a population-based study

BACKGROUND

Ductal carcinoma in situ with microinvasion (DCISM) represents ~1% of all breast cancer cases. Risk factors for lymph node (LN) metastasis and appropriate adjuvant therapy for DCISM are still widely debated.

METHODS

We retrieved DCISM data from the National Cancer Institute's Surveillance, Epidemiology, and End Results registry database (1998-2013). Chi-squared tests and logistic regression models were applied to investigate the potential risks of LN metastasis. Univariate and multivariate Cox proportional hazards regressions were performed to estimate the prognostic factors of DCISM. Survival outcomes were estimated using the Kaplan-Meier method. A 1:1 propensity score matching was used to minimize potential bias.

RESULTS

Overall, 6,219 patients with DCISM met our inclusion criteria. Younger age and higher grade disease were identified as risk factors for LN metastasis. In the multivariable analysis, LN metastasis and chemotherapy were prognostic factors for worse overall survival and breast cancer-specific survival. Furthermore, propensity score matching and subgroup analysis showed that chemotherapy may not be effective for DCISM patients.

CONCLUSION

Younger patients with high-grade disease tend to have LN involved in DCISM. Adjuvant chemotherapy might not be necessary for patients with DCISM.

Impact of microinvasion on breast cancer mortality in women with ductal carcinoma in situ

BACKGROUND

Ductal carcinoma in situ (DCIS) is a neoplastic proliferation of epithelial cells which is confined within the basement membrane of the mammary ductal-lobular system. It is of interest to determine to what extent the potential to metastasize increases for DCIS patients when the basement membrane is breached (i.e. microinvasion is present).

METHODS

We retrieved the records of 525,395 women who had either first primary DCIS or small (≤ 2.0 cm) node-negative invasive breast cancer in the Surveillance, Epidemiology and End Results (SEER) registries database (1990-2013). For each patient, we extracted information on year of diagnosis, age at diagnosis, tumour size, tumour grade, oestrogen receptor status, use of radiotherapy, type of surgery, cause of death and follow-up time. We classified patients into four groups, according to the size of the invasive component of the primary tumour. We estimated the actuarial rate of breast cancer-specific mortality at ten and 20 years for women in each size category.

RESULTS

We identified 161,394 women with pure DCIS, 13,489 women with microinvasive carcinoma (≤ 0.1 cm of invasion), 153,856 women with invasive cancer 0.2-1.0 cm in size and 196,656 women with invasive cancer 1.1-2.0 cm in size. The 20-year actuarial breast cancer-specific mortality rate was 3.8% for women with pure DCIS, was 6.9% for women with microinvasive carcinoma, was 6.8% for women with invasive cancer 0.2-1.0 cm in size and was 12.1% for women with invasive cancer 1.1-2.0 cm in size. The adjusted hazard ratio for death associated with microinvasive carcinoma (vs. pure DCIS) was 2.00 (95% CI 1.76-2.26; p < 0.0001).

CONCLUSIONS

In terms of prognosis, microinvasive cancer more closely resembles small invasive cancer 0.2-1.0 cm) than pure DCIS. For invasive cancers under 1.0 cm, size has little impact on mortality.