Multiple re-excisions versus mastectomy in patients with persistent residual disease following breast conservation surgery

Background: Persistently involved margins following breast conservation surgery (BCS) create a diagnostic dilemma regarding the recommendation of further BCS or mastectomy. Methods: A retrospective review of 276 breast cancer patients who underwent BCS and required additional surgical treatment between 1990-2002 was performed. Results: For treatment of persistently involved margins, 63% of subjects underwent re-excision the first time, 49% the second time, and 37% the third time. The incidence of residual carcinoma increased linearly with the number of initially involved margins (P = .03). Ductal carcinoma-in-situ (DCIS) or infiltrating lobular carcinoma (IFLC) primary histology was associated with a higher rate of residual cancer compared to invasive ductal carcinoma (IFDC) (62% vs. 69% vs. 54%, respectively, P = .56). A trend towards an increased risk of residual cancer in primary tumors <2 cm versus tumors under 2 cm was also evident (63%% vs. 50%, respectively, P = .38). Conclusions: Approximately half of patients repeatedly selected BCS over mastectomy. It is important to realistically discuss the probability of definitive resection with patients who are undergoing breast conservation with re-excision.