MIXED TESTICULAR GERM-CELL TUMORS - MONOCLONAL OR POLYCLONAL

Testicular germ cell tumors (TGCT) of adolescents and adults are, for clinical and pathological reasons, divided in seminomas (SE) and nonse minomatous germ cell tumors (NS). Whether and to what degree these two entities are pathogenetically related is still controversial and a ma tter of debate. TGCT may contain both SE and NS components. Cytogeneti c studies of the SE and NS components of these mixed TGCT might shed l ight on the pathogenetic relationship between both components, Separat e cytogenetic analysis was performed on both components of three cases of mixed TGCT with both SE and NS components. The karyotypes of both components were compared with each other. in one case, the SE and NS c omponent share eight different structural chromosomal abnormalities, i ndicating that the SE and NS component are pathogenetically closely re lated and have a common neoplastic pathway for a considerable length. Both components of the other two cases have, respectively, i(12p) and no structural chromosomal abnormalities in common. Our results, togeth er with data from the literature, indicate that in mixed TGCT with SE and NS components, both components may have either a monoclonal or a p olyclonal origin.