Variant translocations of chromosome 13 in alveolar rhabdomyosarcoma.

In three cases of alveolar rhabdomyosarcoma with variant translocations, two tumors contained an identical translocation, t(1;13)(p36.1;q14); the third tumor contained a t(8;13)(p21;q14). All three patients were 2 years old, markedly younger than the median age for patients with t(2;13)-positive alveolar rhabdomyosarcoma. The alteration of genetic material on chromosome 13 may be of primary importance in the development of alveolar rhabdomyosarcoma.