The development of knowledge of sarcoma of the breast has been handicapped by confusion in classification, a state still prevalent to some extent. This has been due chiefly to the striking variability of the manifestations of sarcoma of the breast (in contrast to the uniformity exhibited by sarcoma in other regions) and to the infrequency of its occurrence—factors all too apparent in any review of the subject in which there is an attempt to place the various forms in well defined groups.
The older literature contains numerous examples of so-called breast sarcoma classified with little regard to histogenesis and subsequent course but largely on gross or microscopic appearance. The prevailing tendency was to name the neoplasms according to the morphologic characteristics of the component elements; the result was the development of a multitude of terms, most of which convey little information as to the tissue of origin. Therefore, although one