Comments on a series of 88 invasive microcarcinomas of the breast

Eighty-eight women with minimal invasive breast cancer were treated at the Istituto Nazionale Tumori of Milan, in the decade 1970-1980. Their tumors were smaller than 0.5 cm in diameter and were clinically assessed as T1N0M0; surgery, consisting of radical or limited procedures, was performed, always with complete axillary dissection. Pathologic assessment showed that axillary lymph nodes presented with metastases in 21.5% of cases. In 1 of N-positive cases, more than 3 nodes were affected, and in 5 cases extracapsular invasion was observed. Five-year actuarial survival, calculated by the life table method, was as high as 90%, demonstrating that these have a favorable prognosis, even when they are treated by limited surgery followed by radiotherapy on the residual breast, provided that the axilla is completely dissected. Minimal invasive breast cancer should consequently be clearly distinguished from other pathologic entities termed as "minimal", such as lobular carcinoma in situ and intraductal carcinoma, for which complete axillary dissection is not worthwhile.