AbstractMalignant triton tumor is a rare histologic variant of malignant schwannoma that shows both neural and skeletal muscle differentiation. In this study, cytogenetic analysis of a recurrent malignant triton tumor of the forearm from a 26‐year‐old female and a primary paraspinal malignant triton tumor from a 27‐year‐old female revealed complex karyotypes displaying multiple numercial and structural abnormalities. Abnormalities shared by both tumors included three copies of chromosome 22 and structural rearrangements of chromosomes 2, 7, and 21 at identical or closely located breakpoints.Genes Chrom Cancer 9:1‐7 (1994).© 1994 Wiley