Clinicopathologic characteristics of mucinous carcinoma of the breast.

The mucinous carcinoma of breast cancer is a relatively rare malignant tumor. This study investigated the clinical and pathologic features of mucinous carcinoma. The medical records of 237 patients with invasive breast cancer who underwent surgery between 1995 and 2006 were reviewed. These cases included 10 patients (4.2%) with mucinous carcinoma. The age of the patients ranged from 43 to 71 years (mean, 55.5 years). The tumor size was T1 in 5 patients and T2 in 5 patients. Lymph node metastasis was diagnosed as being negative in 9 patients and positive in 1 patient. Six patients (60%) were positive both for estrogen and progesterone receptor. The 10-year survival rates of mucinous carcinoma and other types of invasive breast cancer were 87.5% and 80.7%, respectively. Mucinous carcinoma showed a lower incidence of lymph node metastasis than other types of invasive breast cancer. Mucinous carcinoma tended to have a better prognosis in comparison with other types of invasive breast carcinoma.