[Evaluation of resection margins following breast conserving surgery for breast cancer. A multicentric retrospective study].

Abstract

Introduction: Breast conserving surgery for breast cancer requires the analysis of surgical margins. If the tumor is not removed completely, additional treatments (reoperation, boost irradiation) are generally recommended. Aim: To analyze the information content of histopathology reports on surgical margins in consecutive cases of breast conservation for invasive female breast cancer, to evaluate the frequency of incompletely removed tumors and to estimate the rate of further treatments after incomplete removal. Method: Analysis of margin related data of consecutive histopathology reports from 8 Hungarian pathology units with locoregional treatment related data in case of unsafe margins. Results: 386 reports were analyzed after exclusions. 200 and 32 cases were identified as having unsafe margins according to the previous (<5 mm) and the new (0 mm) definition of unclear margin, respectively. Unsafe margins were more common with lobular carcinomas. Specimens with clear margins weighed more. Reoperations for unsafe margins were performed in 43/180 and 12/22 cases according to the previous and the new definitions, respectively. Only 75/137 patients without reoperation received boost irradiation of the tumor bed; information on boost radiotherapy was often missing. Residual cancer was identified in 15/43 reoperated patients, of whom 9 had >0 mm margin distance. Conclusions: Some pathology reports lack information on surgical margins. Unsafe margin rates decreased with the new definition. Residual cancer may be left behind in case of clear margins with no ink on tumor. Neither reoperation, nor boost radiotherapy is given to some patients with unclear surgical margins. Orv Hetil. 2019; 160(26): 1036-1044.