Is the Number or Proximity of Margins Less than 2 mm Associated with an Increased Mastectomy Rate in Patients Attempting Breast Conservation Therapy for Ductal Carcinoma In Situ?

BACKGROUND

Consensus guidelines recommend ≥ 2 mm margins in patients undergoing partial mastectomy (PM) for ductal carcinoma in situ (DCIS). It is unknown whether the number or proximity of margins less than 2 mm is associated with an increased mastectomy rate in patients attempting breast conservation therapy (BCT) for DCIS. The aim of this study is to examine this relationship.

PATIENTS AND METHODS

An institutional database review identified 208 patients with DCIS who underwent PM at a tertiary referral center and community hospitals from July 2020 to June 2023. Patients with a history of breast cancer, previous surgery for breast cancer, ipsilateral invasive carcinoma, papillary carcinoma, Paget's disease, more lobular carcinoma in situ (LCIS) than DCIS present, initial mastectomy, no DCIS present, routine shave margins (of all vectors), and ≥ 2 mm margins of all six vectors were excluded. Selective intraoperative margin re-excisions were included.

RESULTS

A total of 208 patients who met inclusion criteria were retrospectively reviewed. 122 (25%) had one close/positive (< 2 mm) margin and 86 (18%) had two or more close/positive margins. Of the patients with one close/positive margin, 7% (9/122) eventually underwent mastectomy. Of the patients with two or more close/positive margins, 20% (17/86) eventually underwent mastectomy. Overall, no patients with opposing margins underwent mastectomy.

CONCLUSIONS

Patients undergoing PM for DCIS have a mastectomy rate that is increased threefold, with two or more close/positive margins at initial PM, when compared with those with only one close/positive margin. The presence of opposing close/positive margins at initial PM did not increase the mastectomy rate and most were cleared with re-excision.

Multitask deep learning on mammography to predict extensive intraductal component in invasive breast cancer

OBJECTIVES

To develop a multitask deep learning (DL) algorithm to automatically classify mammography imaging findings and predict the existence of extensive intraductal component (EIC) in invasive breast cancer.

METHODS

Mammograms with invasive breast cancers from 2010 to 2019 were downloaded for two radiologists performing image segmentation and imaging findings annotation. Images were randomly split into training, validation, and test datasets. A multitask approach was performed on the EfficientNet-B0 neural network mainly to predict EIC and classify imaging findings. Three more models were trained for comparison, including a single-task model (predicting EIC), a two-task model (predicting EIC and cell receptor status), and a three-task model (combining the abovementioned tasks). Additionally, these models were trained in a subgroup of invasive ductal carcinoma. The DeLong test was used to examine the difference in model performance.

RESULTS

This study enrolled 1459 breast cancers on 3076 images. The EIC-positive rate was 29.0%. The three-task model was the best DL model with an area under the curve (AUC) of EIC prediction of 0.758 and 0.775 at the image and breast (patient) levels, respectively. Mass was the most accurately classified imaging finding (AUC = 0.915), followed by calcifications and mass with calcifications (AUC = 0.878 and 0.824, respectively). Cell receptor status prediction was less accurate (AUC = 0.625-0.653). The multitask approach improves the model training compared to the single-task model, but without significant effects.

CONCLUSIONS

A mammography-based multitask DL model can perform simultaneous imaging finding classification and EIC prediction.

CLINICAL RELEVANCE STATEMENT

The study results demonstrated the potential of deep learning to extract more information from mammography for clinical decision-making.

KEY POINTS

• Extensive intraductal component (EIC) is an independent risk factor of local tumor recurrence after breast-conserving surgery. • A mammography-based deep learning model was trained to predict extensive intraductal component close to radiologists' reading. • The developed multitask deep learning model could perform simultaneous imaging finding classification and extensive intraductal component prediction.

Blood flow on ultrasound imaging is a predictor of lump margin status in breast-conserving patients: a retrospective matching study

PURPOSE

This study investigated the relationship between breast ultrasound features and lump margin status in breast-conserving patients.

METHODS

A single-institution database and medical records system were searched to identify patients who had undergone breast-conserving surgery between 2015 and 2022. Patients were divided into case and control groups based on their postoperative margin status, and different matching methods [case-control matching (CCM) and propensity score matching (PSM)] were used to match the cases and controls at a ratio of 1:1.

RESULTS

Before matching, patients with positive margins were more likely to have a tumor with increased blood flow (OR = 2.90, 95% CI 1.83-4.61, p < 0.001) and microcalcifications (OR = 2.22, 95% CI 1.44-3.42, p < 0.001). Among the 83 pairs of CCM subjects, patients with positive margins were prone to increased blood flow (p = 0.007) and crab sign (p = 0.040). In addition, there was a significant difference in blood flow (p = 0.030) among PSM subjects. After adjusting for the unbalanced factors, the same results were obtained.

CONCLUSIONS

Ultrasound blood flow significantly predicts the status of breast-conserving margins, but further studies are required to verify our findings.

A Comparison of Spectroscopy and Imaging Techniques Utilizing Spectrally Resolved Diffusely Reflected Light for Intraoperative Margin Assessment in Breast-Conserving Surgery: A Systematic Review and Meta-Analysis

Up to 19% of patients require re-excision surgery due to positive margins in breast-conserving surgery (BCS). Intraoperative margin assessment tools (IMAs) that incorporate tissue optical measurements could help reduce re-excision rates. This review focuses on methods that use and assess spectrally resolved diffusely reflected light for breast cancer detection in the intraoperative setting. Following PROSPERO registration (CRD42022356216), an electronic search was performed. The modalities searched for were diffuse reflectance spectroscopy (DRS), multispectral imaging (MSI), hyperspectral imaging (HSI), and spatial frequency domain imaging (SFDI). The inclusion criteria encompassed studies of human in vivo or ex vivo breast tissues, which presented data on accuracy. The exclusion criteria were contrast use, frozen samples, and other imaging adjuncts. 19 studies were selected following PRISMA guidelines. Studies were divided into point-based (spectroscopy) or whole field-of-view (imaging) techniques. A fixed-or random-effects model analysis generated pooled sensitivity/specificity for the different modalities, following heterogeneity calculations using the Q statistic. Overall, imaging-based techniques had better pooled sensitivity/specificity (0.90 (CI 0.76-1.03)/0.92 (CI 0.78-1.06)) compared with probe-based techniques (0.84 (CI 0.78-0.89)/0.85 (CI 0.79-0.91)). The use of spectrally resolved diffusely reflected light is a rapid, non-contact technique that confers accuracy in discriminating between normal and malignant breast tissue, and it constitutes a potential IMA tool.

Immediate or delayed oncoplastic surgery after breast conserving surgery at the Netherlands Cancer Institute: a cohort study of 251 cases

PURPOSE

Oncoplastic surgery (OPS) after breast conserving surgery is preferably performed during the same operation. Offering delayed OPS instead of mastectomy to patients with a high risk of tumor-positive margins allows breast conservation with the option of margin re-excision during OPS, without having to dismantle the reconstruction. We aimed to evaluate surgical outcomes after immediate and delayed OPS.

METHODS

We included early-stage breast cancer patients who underwent OPS at the Netherlands Cancer Institute between 2016 and 2019. Patients were selected for delayed OPS after multidisciplinary consultation if the risk of tumor-positive margins with immediate OPS was considered significant (> 30%). Groups were compared on baseline characteristics and short-term surgical outcomes.

RESULTS

Of 242 patients with 251 OPS, 130 (52%) OPS had neoadjuvant chemotherapy. Immediate OPS was performed in 176 (70%) cases and delayed OPS in 76 (30%). Selection for delayed OPS was associated with tumor size (OR 1.03, 95% CI 1.01-1.04), ILC (OR 2.61, 95% CI 1.10-6.20), DCIS (OR 3.45, 95% CI 1.42-8.34) and bra size (OR 0.76, 95% CI 0.62-0.94). Delayed and immediate OPS differed in tissue weight (54 vs. 67 g, p = 0.034), tissue replacement (51% vs. 26%, p < .001) and tumor-positive margins (66% vs. 18%, p < .001). Re-excision was performed in 48 (63%) delayed OPS and in 11 (6%) immediate OPS. Groups did not differ in complications (21% vs. 18%, p = 0.333). Breast conservation after immediate and delayed OPS was 98% and 93%, respectively.

CONCLUSION

Performing delayed OPS in selected cases facilitated simultaneous margin re-excision without increasing complications, and resulted in an excellent breast conservation rate.

Development and Validation of a Prediction Model for Positive Margins in Breast-Conserving Surgery

Background

The chances of second surgery due to positive margins in patients receiving breast-conversing surgery (BCS) were about 20-40%. This study aims to develop and validate a nomogram to predict the status of breast-conserving margins.

Methods

The database identified patients with core needle biopsy-proven ductal carcinoma in situ (DCIS) or invasive breast carcinoma who underwent BCS in Shanxi Bethune Hospital between January 1, 2015 and December 31, 2021 (n = 573). The patients were divided into two models: (1) The first model consists of 398 patients who underwent BCS between 2015 and 2019; (2) The validation model consists of 175 patients who underwent BCS between 2020 and 2021. The development of the nomogram was based on the findings of multivariate logistic regression analysis. Discrimination was assessed by computing the C-index. The Hosmer-Lemeshow goodness-of-fit test was used to validate the calibration performance.

Results

The final multivariate regression model was developed as a nomogram, including blood flow signals (OR = 2.88, p = 0.001), grade (OR = 2.46, p = 0.002), microcalcifications (OR = 2.39, p = 0.003), tumor size in ultrasound (OR = 2.12, p = 0.011) and cerbB-2 status (OR = 1.99, p = 0.042). C-indices were calculated of 0.71 (95% CI: 0.64-0.78) and 0.68 (95% CI: 0.59-0.78) for the modeling and the validation group, respectively. The calibration of the model was considered adequate in the validation group (p > 0.05).

Conclusion

We developed a nomogram that enables the estimation of the preoperative risk of positive BCS margins. Our nomogram provides a valuable tool for identifying high-risk patients who might have to undergo a wider excision.

Risk factors for the presence of residual disease in women after partial mastectomy for invasive breast cancer: A single institution experience

BACKGROUND

We hypothesize that in addition to specimen margin widths other clinical variables may help predict the presence of residual disease in the lumpectomy bed.

METHODS

Patients with Stage I-III invasive breast cancer (BC) who underwent partial mastectomy (PM) and re-excision from July 2010-June 2015 were retrospectively reviewed. Bivariate analyses were conducted using two-sample t-tests for continuous variables and Fisher's Exact tests for categorical variables. A multivariate logistic regression was then performed on significant bivariate analyses variables.

RESULTS

ne-hundred and eighty-four patients were included in our analysis; 47% had residual disease on re-excision, while 53% had no residual disease. Tumor and nodal stage, operation type, type of disease present at margin, and number of positive margins were significantly associated with residual disease. On multivariate logistic regression, DCIS alone at the margin (p = 0.02), operation type (PM with cavity margins) (p = 0.003), and number of positive margins (3 or more) (p < 0.001) remained predictive of residual disease at re-excision.

CONCLUSION

Based on a more comprehensive review of the initial pathology, there are additional factors that can help predict the likelihood of finding residual disease and help guide the surgeon in the decision for re-excision.

Minimally invasive tumor bed implant (MITBI) and peri-operative high-dose-rate brachytherapy (PHDRBT) for accelerated minimal breast irradiation (AMBI) or anticipated boost (A-PHDRBT-boost) in breast-conserving surgery for ductal carcinoma in situ

Purpose

To evaluate our institutional experience of minimally invasive tumor bed implantation (MITBI) during breast-conserving surgery (BCS) for ductal carcinoma in situ (DCIS) to deliver peri-operative high-dose-rate brachytherapy (PHDRBT) as accelerated minimal breast irradiation (AMBI) or anticipated boost (A-PHDRBT-boost).

Material and methods

Patients older than 40, with clinical and radiological unifocal DCIS < 3 cm were considered potential candidates for accelerated partial breast irradiation (APBI) and were implanted during BCS using MITBI-technique. Patients who in final pathology reports showed free margins and no other microscopic tumor foci, received AMBI with PHDRBT (3.4 Gy BID in 5 days). Patients with adverse features received A-PHDRBT-boost with post-operative external beam radiotherapy (EBRT).

Results

Forty-one patients were implanted, and 36 were treated and analyzed. According to final pathology, 24 (67%) patients were suitable for AMBI and 12 (33%) were qualified for A-PHDRBT-boost. Reoperation rate for those with clear margins was 16.6% (6/36); this rate increased to 33% (4/12) for G3 histology, and 66% (4/6) were rescued using AMBI. Early complications were documented in 5 patients (14%). With a median follow-up of 97 (range, 42-138) months, 5-year rates of local, elsewhere, locoregional, and distant control were all 97.2%. 5-year ipsilateral breast tumor recurrence rates (IBTR) were 5.6% (2/36), 8.3% (2/24) for AMBI, and 0% (0/12) for A-PHDRBT-boost patients. Both instances of IBTR were confirmed G3 tumors in pre-operative biopsies; no IBTR was documented in G1-2 tumors. Cosmetic outcomes were excellent/good in 96% of AMBI vs. 67% in A-PHDRBT-boost (p = 0.034).

Conclusions

The MITBI-PHDRBT program allows selection of patients with excellent prognoses (G1-2 DCIS with negative margins and no multifocality), for whom AMBI could be a good alternative with low recurrence rate, decrease of unnecessary radiation, treatment logistics improvement, and over-treatment reduction. Patients whose pre-operative biopsy showed G3 tumor, presents with inferior local control and more risk of reoperation due to positive margins.

Predictors of Reexcision following Breast-Conserving Surgery for Ductal Carcinoma In Situ

BACKGROUND

Reexcision following breast-conserving surgery (BCS) in women with ductal carcinoma in situ (DCIS) results in adjuvant treatment delays, higher health care costs, and undesirable cosmetic outcomes. The purpose of this study is to determine patient, imaging, pathological, and surgical predictors of reexcision following BCS for DCIS.

PATIENTS AND METHODS

A retrospective review of women with DCIS who had BCS from 2007 to 2016 was conducted. Patient, imaging, pathological, and surgical features, in addition to surgical outcomes, were collected from medical records. Standard statistical tests were used to compare features between patients who did and did not undergo at least one reexcision. A multivariable logistic regression model was fit to assess features associated with reexcision.

RESULTS

A total of 547 women (mean age 59 years; range 30-88 years) diagnosed with DCIS at core needle biopsy underwent BCS. Of all women, 31.6% (173/547) had at least one reexcision. With multivariable analysis, features associated with reexcision included younger patient age (adjusted odds ratio [aOR] 0.98, 95% confidence interval [CI] 0.97-1.0, p = 0.049), African-American race (aOR 2.66, 95% CI 1.13-6.26, p = 0.03), biopsy modality of ultrasound (aOR 2.35, 95% CI 1.22-4.53, p = 0.01), and earlier year of surgery (aOR 0.92, 95% CI 0.86-0.98, p = 0.01). No pathological features of DCIS were associated with reexcision risk.

CONCLUSIONS

In our cohort of nearly 550 women with DCIS who underwent BCS, 31.6% had at least one reexcision. Features associated with reexcision include younger patient age, African-American race, biopsy modality of ultrasound, and earlier year of surgery.

Do All Positive Margins in Breast Cancer Patients Undergoing a Partial Mastectomy Need to Be Resected?

BACKGROUND

Positive margins have been reported in 20% to 40% of patients undergoing a partial mastectomy, often resulting in re-excision. How often the re-excision yields additional cancer and whether there are predictors of residual disease remain unknown.

STUDY DESIGN

Patients who had a positive margin (defined as tumor at ink for patients with invasive disease or within 1 mm for patients with ductal carcinoma in situ) in the SHAVE (A Randomized Controlled Trial of Routine Shave Margins Versus Standard Partial Mastectomy in Breast Cancer Patients) trial before randomization were evaluated to determine the rate of additional disease either in cavity shave margins or at re-excision. Details of the SHAVE trial can be found elsewhere.

RESULTS

Of the 235 patients in the trial, 82 (34.9%) had a positive margin before randomization; 58 of these patients underwent either cavity shave margins excision or a re-excision of the positive margin(s). Twenty-one (36.2%) patients had residual disease. On bivariate analysis, residual disease was associated with younger patient age (median 51 vs 62 years; p = 0.007), and the presence of high-grade ductal carcinoma in situ (57.1% vs 31.3% for grade 2 and 0% for grade 1; p = 0.025). The following factors were not associated with further disease: patient race; ethnicity; BMI; volume of resection; number of positive margins; extent of ductal carcinoma in situ; and extent, grade, and histologic subtype of invasive cancer. On multivariate analysis, only patient age younger than 60 years remained a significant predictor of residual disease (odds ratio 3.920; 95% CI 1.081 to 14.220; p = 0.038).

CONCLUSIONS

Positive margins are associated with further disease in more than one-third of patients and, aside from young age, there are no predictors of this. These findings support continued re-excision of positive margins, particularly in patients younger than 60 years of age.

Focally positive margins in breast conserving surgery: Predictors, residual disease, and local recurrence

BACKGROUND

Re-excision after breast conserving surgery (BCS) for invasive breast cancer (IBC) can be omitted for focally positive margins in the Netherlands, but this guideline is not routinely followed. Focally positive and extensively positive margins have rarely been studied separately and compared to negative margins regarding clinicopathological predictors, residual disease incidence, and local recurrence.

METHODS

All females with BCS for Tis-T3, without neo-adjuvant chemotherapy between 2005 and 2014 at one university hospital were included. Clinicopathological and follow-up information was collected from electronic patient records. Index tumor samples from all patients with re-excision were reviewed by one pathologist. Margins were classified as negative (≥2 mm width), close (<2 mm width), focally positive (≤4 mm length of tumor touching inked margin), or extensively positive (>4 mm length).

RESULTS

From 499 patients included, 212 (43%) had negative, 161 (32%) had close, 59 (12%) had focally positive, and 67 (13%) had extensively positive margins. Increasingly involved margins were associated with lobular type, tumor size, and adjacent DCIS in IBC patients and lesion size in purely DCIS patients. In IBC patients, 17%, 49%, and 77% had re-excision after close, focally positive, and extensively positive margins and residual disease incidence was 55%, 50%, and 70% respectively. In purely DCIS patients, 26 (65%), 13 (87%), and 16 (94%) had re-excision after close, focally positive, and extensively positive margins and residual disease incidence was 39%, 46%, and 90% respectively.

CONCLUSION

Incidence of residual disease after focally positive margins was not different from close margins, but was significantly higher after extensively positive margins. We recommend quantifying extent of margin involvement in all pathology reports.