Operative outcomes of conventional specimen radiography versus in-operating room specimen radiography in radioactive seed-localized segmental mastectomies.

INTRODUCTION

In-operating room specimen radiography (ORSR) has not been studied among women undergoing radioactive seed localization (RSL) for breast cancer surgery and had the potential to decrease operative time and perhaps improve intraoperative margin management.

METHODS

One hundred consecutive RSL segmental mastectomies among 98 patients using ORSR were compared to 100 consecutive segmental mastectomies among 98 patients utilizing conventional radiography (CSR) prior to the initiation of ORSR from December 2013 to January 2015 after radioactive seed localization. Final pathologic margins were considered to be 10 mm for all cases of no residual disease after biopsy or neoadjuvant therapy, but such patients were excluded from analyses involving tumor size. All patients' specimens were subjected to intraoperative pathologic consultation in addition to ORSR or CSR.

RESULTS

The median age of the cohort was 65 years (range 36-97), and the median tumor size was 1 cm. There were no differences between the ORSR and CSR groups in age, tumor size, percentage of cases with only DCIS, and percentage of cases with microcalcifications. The ORSR group had a statistically significant lower BMI. Mean operative time from cut-to-close was not significantly different (ORSR 77 min, SD 24.8 vs CSR 76 min, SD 24.8, p = 0.75). There was no statistical difference in mean closest final pathologic margin (4.99 mm, SD 3.3 vs 4.88 mm, SD 3.5, p = 0.9). The percentage undergoing intraoperative margin re-excision (ORSR 40%, CR 47%, p = 0.31) and the mean total number of margins excised intraoperatively (ORSR 0.9, CR 1.0 p = 0.65) were similar. The rate of any margin <2 mm was 14% vs 12% for ORSR and CR, respectively (p = 0.64). The mean specimen volume for ORSR was 76cm3 (SD 101.8) vs 90cm3 (SD 61.2) for CSR; this difference was not statistically significant (p = 0.25). The mean ratio of segmental mastectomy volume to maximum tumor diameter was less for ORSR (82.7cm2 vs 139.4cm2, p = 0.014).

CONCLUSION

ORSR for RSL breast surgery, in the setting of routine intraoperative pathology consultation, does not significantly impact operative time, the rate or number of additional intraoperative margins excised, the number of reoperations for margins, or the width of final pathological margins. ORSR was associated with a decrease in the volume of segmental mastectomies relative to the tumor diameter.