Surgical Outcome of Patients with Core-Biopsy-Proven Nonpalpable Breast Carcinoma: A Large Cohort Follow-Up Study

BACKGROUND: Breast-conserving surgery (BCS) is the preferred treatment for nonpalpable breast carcinoma. The outcome, however, may be disappointing. In this study surgical outcome in a large cohort of patients diagnosed with nonpalpable breast carcinoma is evaluated. METHODS: In 833 patients with 841 nonpalpable breast carcinomas the number of re-excisions and type of surgical procedures was calculated and summed per patient. Subsequently, the number of conversions to mastectomy and the number of days until complete tumor removal were analyzed. In a subgroup analysis the patients with an in situ carcinoma were compared with the patients with an invasive carcinoma. RESULTS: The initial surgery consisted of BCS for 589 tumors (70%) and of mastectomy for 242 tumors (29%). For ten tumors (1%) the initial surgery was unknown. After BCS, 158/589 tumors (27%) required a re-excision: 116/337 (34%) for the in situ carcinomas and 63/504 (13%) for the invasive carcinomas (p = 0.0001). The number of conversions from BCS to mastectomy was 106/589 (18%): 66/241 (28%) in patients diagnosed with an in situ carcinoma versus 40/348 (11%) in patients with an invasive carcinoma (p = 0.0001). The median number of days until complete tumor removal was 28, being 38 days for the in situ carcinomas and 25 days for the invasive carcinomas (p = 0.0001). CONCLUSIONS: There is room for improvement in the surgical treatment of nonpalpable breast carcinoma, especially the relatively favorable in situ carcinoma, as it requires significantly more excisions, mastectomies, conversions to mastectomy, and days for complete removal.