Initial Margin Status for Invasive Ductal Carcinoma of the Breast and Subsequent Identification of Carcinoma in Reexcision Specimens

Abstract

Margin status of lumpectomy specimens is related to frequency of local recurrence. Optimal surgical technique requires microscopic margins free of carcinoma by at least 2 mm. Recurrence following lumpectomy is associated with residual carcinoma secondary to inadequate resection. To review our series of breast excisions to determine the frequency of residual carcinoma for positive, close, and negative margins. We reviewed lumpectomies and excisional biopsies for invasive ductal carcinoma that had subsequent reexcisions. Margin status of specimens was recorded as positive, less than 1 mm, 1 to 2 mm, or greater than 2 mm. A total of 123 lumpectomies and excisional biopsies of invasive ductal carcinoma with reexcision were reviewed. Residual invasive carcinoma was found in 44% (17), 25% (6), 28% (8), and 16% (5) of cases with positive, less than 1 mm, 1 to 2 mm, and greater than 2 mm margins, respectively. Residual invasive carcinomas were found in 57% (8), 100% (5), 67% (2), and 100% (2) of mastectomies with positive, less than 1 mm, 1 to 2 mm, and greater than 2 mm margins, respectively, in the initial lumpectomy or excisional biopsy. Frequency of residual invasive carcinoma was related to margin status of the original lumpectomy/biopsy. Even when margins were positive, most reexcisions were free of carcinoma. Residual invasive carcinoma was found in greater than 25% of patients with margins less than 2 mm, supporting reexcision for patients with margins of less than 2 mm. Sixteen percent of cases with margins greater than 2 mm harbored residual invasive carcinoma. Evaluation of margin status was complicated by tissue distortion and fragmentation.