Clinicopathologic Characteristics of Typical Medullary Breast Carcinoma: A Retrospective Study of 117 Cases

PURPOSE: This study analyzed the clinicopathologic characteristics of typical medullary breast carcinoma (TMBC) in a cohort of Chinese patients. METHODS: We conducted a retrospective review of clinical data including general information, pathologic results, treatment regimens, and patient survival in cases of TMBC diagnosed between February 2004 and April 2011. RESULTS: A total of 117 patients were enrolled, with a median age of 52 years (range, 28∼92 years). Stage I and II disease accounted for 31.6% and 61.6% of the cases, respectively. Hormonal receptor negative disease (estrogen receptor negative, 68.4%; progestogen receptor negative, 86.3%) was more prevalent in this population. Human epidermal growth factor receptor-2 (HER-2) positivity was 20.5%, while equivocal and HER-2 negative cases represented 16.2% and 63.2% of the cohort. The triple-negative, luminal, and HER-2 overexpressing subtypes constituted 44.4%, 31.6%, and 15.4% of the cases, respectively. The various TMBC subtypes showed no differences regarding tumor size, rates of lymph node(s) metastasis, TNM staging, treatment regimens, and 2-year recurrence rates. However, patients with triple-negative disease were more likely to be younger, when compared to those with luminal disease (P = 0.002). At a median follow-up of 56 months (range, 2–112 months), the 2-year disease-free survival and overall survival rates were 99.1% and 98.2%, respectively. CONCLUSION: Early stage disease dominated the study cohort, and at two years after surgery, recurrence was extremely low. The heterogeneity of molecular subtypes was clearly shown, and no apparent differences were found among the clinicopathologic characteristics of the triple-negative, luminal, and HER-2 overexpressing subtypes.