Five year results of radical mastectomy for breast cancer, by a sternal splitting, intrapleural en bloc resection of the internal mammary lymph nodes.

A new operative method of extended radical mastectomy enables complete resection of the axillary and internal mammary lymph nodes. In this paper, we present the histological analysis of the internal mammary involvement, and the estimated 5 year survival rate, of 100 patients with breast cancer of Stage I, II or III, who underwent this operation. The incidences of axillary and internal mammary involvements were 41 per cent and 17 per cent, respectively. The metastases in the internal mammary lymph node chain were located from just below the supraclavicular vein to the third intercostal space along the internal mammary vessels. The types of lymphatic invasion observed in the internal mammary chain were lymph node metastases in 88 per cent, metastatic lesion in the lymphoid tissue in 29 per cent and cancer cell emboli in the lymphatic channel in 71 per cent. The overall estimated 5 year survival rate was 90.5 per cent. Where there was internal mammary involvement, the estimated 5 year survival rates for those with no axillary lymph node metastasis, those with fewer than 3 metastatic axillary lymph nodes, and those with more than 4 metastatic axillary lymph nodes were 100 per cent, 80 per cent and 31.2 per cent, respectively. Although the assumption that more aggressive surgical removal of the primary lesion and the regional lymphatic spread gives a higher cure rate has not been proved, this extended radical mastectomy with adjuvant chemoendocrine therapy seems to give a higher 5 year survival rate for patients with internal mammary involvement.