RHABDOMYOSARCOMA IN ADULTS

Rhabdomyosarcomas occur in adults in one of two forms; as sporadic cas es of the juvenile histological types and more commonly, if controvers ially, as the major adult form, pleomorphic rhabdomyosarcoma. This rev iew documents the historical background to the fluctuating diagnostic popularity of pleomorphic rhabdomyosarcoma, together with a presentati on of its defining clinicopathologic characteristics, and presents the clinicopathologic features of the juvenile types as they occur in adu lts. The concept of pleomorphic rhabdomyosarcoma as a distinct clinico pathologic entity, presenting as an aggressive, predominantly spindle- cell tumor arising in the skeletal musculature of middle-aged adults a nd defined by the presence of large, pleomorphic tumor cells, which sh ow, at least focally, immunophenotypic or ultrastructural sarcomeric m uscle differentiation, is discussed and supported. Copyright (C) 1994 by W.B. Saunders Company