Routine cavity shaves following breast conserving surgery; friend or foe?

Impact of cavity shave margins in patients with ductal carcinoma in situ undergoing conserving breast surgery

Aim

The main challenge during breast-conserving surgery (BCS) is to obtain clear margins, especially in patients with ductal carcinoma in situ (DCIS) due to the absence of well-defined nodules. Many surgical approaches have been used in an attempt to reduce the positive margin rate. The aim of this retrospective study is to compare the cavity shave margin technique with standard surgery and the intraoperative evaluation of surgical margins.

Methods

This is a single-center retrospective study analyzing margin status, need for re-excision, and surgical time in a cohort of 227 patients who underwent surgery from September 2016 to September 2022.

Results

In patients subjected to cavity shaving, we reported a significant reduction in positive margins of 17.1% versus 28.7% (p-value = 0.042). Also, a difference in terms of surgical re-excision was reported as p-value = 0.039 (12.4% versus 23.8%, respectively, for the cavity shave and control group). In the multivariate analysis, intraoperative evaluation of the margins was a risk factor for margins re-excision (Wald = 4.315, p = 0.038, OR: 2.331 [95% CI: 1.049-5.180]). Surgical time was lower in patients subjected to cavity shaves (p = 0.024), and the relative mean time was 68.4 min ± 37.1 min in the cavity shave group versus 93.9 min ± 40.6 min in the control group.

Conclusion

The cavity shave margin technique in conserving breast surgery results in a reduction in positive margin rate, surgical re-excision, and operative time.

Pragmatic guide to the macroscopic evaluation of breast specimens

The pathological assessment of a breast surgical specimen starts with macroscopic evaluation, arguably one of the most critical steps, as only a small percentage of the tissue is examined microscopically. To properly evaluate and select tissue sections from breast specimens, it is essential to correlate radiological findings, prior biopsies, procedures and treatment with the gross findings. Owing to its fatty nature, breast tissue requires special attention for proper fixation to ensure appropriate microscopic evaluation and performance of ancillary studies. In addition, knowledge of the information necessary for patient management will ensure that these data are collected during the macroscopic evaluation, and appropriate sections are taken to obtain the information needed from the microscopic evaluation. Herein, we present a review of the macroscopic evaluation of different breast specimen types, including processing requirements, challenges and recommendations.

Cavity Shave Margins in Breast Conservative Surgery a Strategy to Reduce Positive Margins and Surgical Time

Background: Resection of additional tissue circumferentially around the cavity left by lumpectomy (cavity shave) was suggested to reduce rates of positive margins and re-excision. Methods: A single center retrospective study which analyzed margins status, re-excision, and surgical time in patients who underwent breast conserving surgery and cavity shave or intraoperative evaluation of resection margins. Results: Between 2021 and 2023, 594 patients were enrolled in the study. In patients subjected to cavity shave, a significant reduction in positive, focally positive, or closer margins was reported 8.9% vs. 18.5% (p = 0.003). No difference was reported in terms of surgical re-excision (p < 0.846) (5% vs. 5.5%). Surgical time was lower in patients subjected to cavity shave (<0.001). The multivariate analysis intraoperative evaluation of sentinel lymph node OR 1.816 and cavity shave OR 2.909 were predictive factors for a shorter surgical time. Excluding patients subjected to intraoperative evaluation of sentinel lymph node and patients with ductal carcinoma in situ, patients that underwent the cavity shave presented a reduced surgical time (67.9 + 3.8 min vs. 81.6 + 2.8 min) (p = 0.006). Conclusions: Cavity shaving after lumpectomy reduced the rate of positive margins and it was associated with a significant reduction in surgical time compared to intraoperative evaluation of resection margins.

Cavity shaving for invasive breast cancer conservative surgery: Reduced specimen volume and margin positive rates

INTRODUCTION

The cavity shaving (CS) technique was described in breast conserving surgery to reduce the rate of reoperation avoiding the need for intraoperative margin analysis. This study assesses differences in the rates of involvement of the surgical margin (requiring further surgery) and volume of surgical specimens, depending on the use or not of this technique.

MATERIAL AND METHODS

A retrospective cohort study was conducted in patients with breast carcinoma who underwent breast conserving surgery between 2013 and 2019. They were divided into two groups depending on whether the cavity shaving technique was used or not. Primary outcomes of the study included presence of final margin involvement, requiring need for further surgery, and the volume of excised tissue comparing the study groups.

RESULTS

A total of 202 cases were included: 92 in the control group and 110 in the cavity shaving group. Significant differences were found regarding involvement of the final margin (19.57% control group vs. 4.55% cavity shaving group; p = 0.010). The volume of additional surgical specimens were significantly greater in the traditional technique group than in the shaving technique (46.43 vs 13.32 cm³; p = 0.01) as was total specimen volume (143.40 vs 100.63 cm³; p = 0.022).

CONCLUSIONS

CS can reduce the positive margin and re-excision rates without larger-volume resections and should therefore be considered a routine technique in BCS for early-stage breast cancer.