Carcinosarcomas: current perspectives and an historical review of nosological concepts.

The origins of the concepts pertaining to the histogenesis of "carcinosarcomas" (CS) can be traced to theories that were advanced more than 100 years ago. Since that time, debate has continued over the clonality of these neoplasms and their corresponding lineages of differentiation. This article considers the historical aspects of CS and attempts to place these premises in a modern perspective. A review of current ultrastructural, cell-culture, and immunohistological data is used to support a monoclonal nature for carcinosarcoma, and to suggest that "sarcomatoid carcinoma" is a more apt designation for this tumor entity.