Reexcision for positive margins in breast cancer: A predictive score of residual disease

Bracketed Localization in Breast-Conserving Surgery: Indications and Success Rates From a Single, High Volume, Academic Breast Cancer Center

BACKGROUND

Bracketed localization is a technique used to help localize lesions for breast-conserving surgery (BCS). To date, there are no guidelines for when bracketed localization should be used in clinical practice. Based on our experience, we aim to provide criteria that should prompt surgeons to consider bracketing.

METHODS

A single-institution retrospective chart review was performed on patients who underwent bracketed localization for BCS between 2015 and 2021. Lesion characteristics were recorded including lesion span, number of lesions, histology type on core needle biopsy and surgical specimen, margin status, and need for additional surgery.

RESULTS

One hundred and thirteen cases were analyzed. Imaging showed an average lesion span of 5.0-cm. Multifocal lesions represented 45% of cases. Ductal carcinoma in situ (DCIS) was a histological component in 64% of core needle biopsies and 76% of surgical specimens. Negative margins were achieved in 82% of patients on the first excision. Additional surgery was performed in 17% of patients. Invasive lobular carcinoma had the highest additional surgery rate at 23%. Negative margins with BCS were achieved in 96% of cases, including those with successful re-excision.

DISCUSSION

This descriptive study shows that bracketed localization was most often employed for patients with large lesion spans, multifocality, and a DCIS or invasive lobular component. While these characteristics are typically associated with higher rates of positive margins, our cohort's rate of additional surgery was comparable to the national average for all BCS operations. These results argue that surgeon utilization of bracketed localization may be beneficial in these clinical scenarios.

Outcomes of Margin Reexcision after Oncoplastic Breast Reduction

Tissue rearrangement after an oncoplastic breast reduction may complicate identification of margins during reexcision. Little is known about outcomes of reoperation in this setting.

Radiological Underestimation of Tumor Size Influences the Success Rate of Re-Excision after Breast-conserving Surgery

Objective

Failure to achieve adequate margins after breast-conserving surgery often leads to re-excision, either by repeat breast-conserving surgery (BCS) or by mastectomy. Despite the high frequency of this problem, the success rate of achieving adequate margins by repeat BCS is not well documented. The objective of this study was to determine the success rate of repeat BCS and identify the factors influencing that rate.

Materials and Methods

A retrospective review was performed of all women undergoing repeat BCS for inadequate margins after initial BCS in our breast unit between 2013 and 2019. Univariate and multivariate analyses were carried out to identify the factors influencing how often adequate margins were achieved after repeat BCS.

Results

One hundred fifty-four patients underwent repeat BCS after initially inadequate margins, of which adequate margins were achieved in 82%. Patients with successful repeat BCS had smaller tumors, had less underestimation of tumor size on imaging, and were less likely to have had cavity shaves taken at their initial BCS. A tumor size more than 50% larger than predicted by imaging was independently associated with failure of repeat BCS in multivariate analysis (odds ratio: 3.6, 95% CI: 1.41-9.20, p = 0.007). Underestimation of tumor size by imaging was commoner and more extensive in patients with larger tumors and those with ductal carcinoma in situ.

Conclusion

Re-excision by cavity shaves has a high success rate and should be offered to all patients who are deemed suitable for the procedure. Patients whose tumors are more than 50% larger than predicted by imaging should be counseled about the higher risk of failure.

Factors predicting residual disease on re-excision after breast conserving surgery

INTRODUCTION

Breast conserving surgery is the standard of care for early breast cancer, however in a quarter of patients, satisfactory margins are not achieved, usually leading to re-excision. Residual disease is found in less than half of these re-excisions, leading to increased morbidity, poorer cosmesis and increased cost, possibly with no oncological benefit. Our study aimed to identify a group of patients with unsatisfactory margins but a low risk of residual disease, who may be able to avoid re-excision.

METHODS AND MATERIALS

All patients from our unit undergoing re-excision for unsatisfactory margins after breast conserving surgery between January 2013 and October 2019 were identified. Pathological factors predicting residual disease were investigated using univariable and multivariable analysis.

RESULTS

220 patients were included. 90 (41 %) had residual disease. Residual disease was more likely in those having mastectomy than cavity shaves (61 % vs 32 %, p < 0.0001). Residual disease increased in a linear fashion with number of involved margins and with increasing tumour size. Tumour size <20 mm (p = 0.045), a pathological to radiological tumour size ratio less than 1.5 (p < 0.0001) and disease-free cavity shaves taken at initial surgery (p = 0.041) were all independent predictors of a low chance of residual disease on multivariable analysis. Patients with all three factors had a 14 % chance of residual disease.

CONCLUSIONS

More than half of patients undergo potentially unnecessary re-excision, and patients with small, radiologically obvious tumours are less likely to have residual disease. The decision on re-excision should include these factors in addition to the margin status.

Prognostic factors for residual occult disease in shave margins during partial mastectomy

PURPOSE

Shave margins have been shown to decrease positive final margins in partial mastectomy. We investigated prognostic factors associated with residual disease in shave margins.

METHODS

Patients with invasive breast carcinoma and ductal carcinoma in situ (DCIS) who had circumferential shave margins excised during lumpectomy were abstracted from a retrospective database from 2015 to 2018. We defined residual occult disease (ROD) as either (1) residual disease in a shave margin when the initial lumpectomy specimen had negative margins or (2) residual disease in a shave margin that did not correspond with the positive lumpectomy margin. We identified the frequency of ROD and conducted logistic regression analysis to identify associated prognostic factors.

RESULTS

166 Patients (139 invasive carcinoma, 27 DCIS) were included with median follow-up of 28 months (9-50 months). Residual occult disease existed in 34 (24.5%) with invasive carcinoma and 8 (29.6%) with DCIS. In univariate analyses of the invasive group, invasive lobular carcinoma and a positive initial, non-corresponding lumpectomy margin were predictive of ROD (OR 3.63, p = 0.04, OR 3.48, p = 0.003 respectively). In multivariate analysis, a positive lumpectomy margin remained significant, p = 0.007. No variables were associated with ROD in DCIS.

CONCLUSION

Residual occult disease was shown to be a frequent event in this analysis of lumpectomy with circumferential shave margins. Having a positive initial lumpectomy margin was predictive of ROD in a non-corresponding margin. Surgeons should consider not being selective in their shave margins or margin of re-excision if shave margins were not obtained in their initial surgery.

Handheld macroscopic Raman spectroscopy imaging instrument for machine-learning-based molecular tissue margins characterization

SIGNIFICANCE

Raman spectroscopy has been developed for surgical guidance applications interrogating live tissue during tumor resection procedures to detect molecular contrast consistent with cancer pathophysiological changes. To date, the vibrational spectroscopy systems developed for medical applications include single-point measurement probes and intraoperative microscopes. There is a need to develop systems with larger fields of view (FOVs) for rapid intraoperative cancer margin detection during surgery.

AIM

We design a handheld macroscopic Raman imaging system for in vivo tissue margin characterization and test its performance in a model system.

APPROACH

The system is made of a sterilizable line scanner employing a coherent fiber bundle for relaying excitation light from a 785-nm laser to the tissue. A second coherent fiber bundle is used for hyperspectral detection of the fingerprint Raman signal over an area of 1  cm2. Machine learning classifiers were trained and validated on porcine adipose and muscle tissue.

RESULTS

Porcine adipose versus muscle margin detection was validated ex vivo with an accuracy of 99% over the FOV of 95  mm2 in ∼3  min using a support vector machine.

CONCLUSIONS

This system is the first large FOV Raman imaging system designed to be integrated in the workflow of surgical cancer resection. It will be further improved with the aim of discriminating brain cancer in a clinically acceptable timeframe during glioma 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.