Studies on the metastasis of breast cancer to lymph nodes. II. Diagnosis of metastasis to internal mammary nodes using radiocolloid

As the method for the diagnosis of metastasis of breast cancer to internal mammary nodes, 198Au colloid was used in parasternal scintigram. In the internal mammary nodes, the rate of correct diagnosis was 90% in the cases where diagnosis of positive metastasis was obtained, 44. 5% in whom metastasis was suspected, and 100% in whom diagnosis of negative metastasis was made. In the subclavian nodes, corresponding values were 69.0%, 34.5%, and 100% indicating poorer diagnostic rate. Examination on the relationship between metastasis to the lymph nodes and scintigram revealed more intense spots in the lymph nodes with very small metastasis than on normal side. As the metastatic portion increases in size, spots become less intense until finally the spots are cold as the whole lymph nodes are occupied by the cancer tissue. As the site of the tumor not only the medial side but also lateral side are involved in Stage I in a high rate of lymph node metastasis. Need of complete removal of internal mammary nodes was urgently suggested.