Value of cytogenetics in the differential diagnosis of the small round cell tumors of childhood.

Small round cell tumors are among the most common problems in the differential diagnosis of cancer, even when more sophisticated histological techniques are utilized (Ezinger and Weiss: In Soft Tissue Tumors. St. Louis: CV Mosby, 1988, pp 668-683). Six cases of small round cell tumors are described the diagnosis of which was particularly difficult. Cytogenetic analysis provided useful information in all of them in making the definitive diagnosis. The reported cases stress the value of cytogenetic methods in approaching difficult diagnostic problems.