The literature on the sites of metastasis of primary carcinomas of the breast consists of amazingly few specific contributions. Of course, all leading textbooks and comprehensive studies of tumors in general and of cancers of the breast in particular refer to the various locations of the metastatic deposits, but they either mention only the lymph nodes, lungs, liver and bones or refer to old, apparently out of date studies on this subject. Thus, Ewing1in 1940, in regard to sites of metastasis, cited Gross's2work on carcinoma of the breast, a study published in 1888, when as a rule only macroscopic evidence of metastasis was available. There are reports of a few instances of what were thought to be unusual sites of metastasis, or one may find rarely a series of cases of carcinoma of the breast with metastases. Most often, however, either the latter are clinical reports