Are we Over Treating Ductal Carcinoma in Situ? – Single Center Experience

Abstract

Background and Aim: Breast cancer is the most common cancer among females worldwide. Ductal carcinoma in situ (DCIS) is a heterogeneous group of neoplastic lesions confined to the breast ducts with the absence of the basement membrane infiltrations. It is usually diagnosed accidently as micro calcifications on mammograms. Materials and Methods: This is a retrospective cohort study which includes all patients who were managed surgically as cases of DCIS at Royal hospital between 2006 and 2019. Clinicopathological data were collected for all patient. The samples were divided into three groups according to their pathological analysis: Positive margin, close margin (0.1 mm to 1.9 mm), and negative margin group (> 2 mm). The recurrence rate for each group was assessed. A p-value <0.05 was considered statistical significant. Results: 72 patients with pure DCIS were included in the present analysis, the mean age was 47.9 years. Ten (13.0%) patients had a positive margin, 29 (37.7%) patients had a close margin, and 33 (42.9%) patients had a negative margin. There was recurrence in 3 patients) 30%) in positive margin group and 7 patients (70%) had no recurrence. On the other hand, 5 patients (17.2%) in close margin group and 1 patient (3%) in clear margin group had recurrence. The recurrence rate was higher in the non-re-excision group compare to the re-excision group. In univariate analysis, there was a significant difference in IBTR by comparing positive versus close and negative margins of excision (p = 0.040). Conclusion: The optimal margin for DCIS tumors remain controversial, nonetheless, our study highlighted the importance and the effect of following the current recommendations of a minimal 2 mm margin width in the breast conserving surgery of DCIS. Also, we have concluded that radiotherapy and hormonal therapy cannot replace obtaining a clear margin of > 2 mm after breast conserving surgery in DCIS.