Ins(10;19) in an endometrial stromal sarcoma.

A 37-year-old woman with a history of bilateral mesenchymal cystic hamartomata of the lung was subsequently found to have low-grade endometrial stromal sarcoma. Cytogenetic analysis of the uterine tumor revealed, in all metaphases, an unusual derivative chromosome generated by the insertion of chromosome 19 into chromosome 10 at the level of its centromere [ins(10;19)(p11;p13q13)].