Studies on the factors inducing metastasis of breast cancer to lymph node. I. Lymph flow in the thoracic wall

The mode of lymph flow from the breast to the regional lymph node was studied using 1llSAu colloid, to ascertain the concept of lymph node of Groups 1, 2, and 3. Lymph flow through the internal mammary nodes was found to be abundant. Especially so when 1llSAu colloid was injected into the lower half of the breast, there was observed more abundant flow than that to axillary lymph nodes. Therefore, it was concluded that regardless of the site of occupation of a tumor, internal mammary nodes should be con· sidered to be of Group 1. Lymph flow through the subclavian nodes proved to be always less than that to the axillary nodes or internal mammary nodes. The rate of the lymph flow appearance on the scintigram was about 20%. Whether the subclavian nodes should be classified as Group 1 or 2 should be further studied. The rate of supraclavicular node visualization was below 3%. Therefore, the supraclavicular nodes should be considered to be Group 2. When these results are applied to the current rule of handling of breast cancer, discrepancy occurs in the Stage number and R-numer.