Thymolipoma: clues to pathogenesis revealed by cytogenetics.

The pathogenesis of thymolipoma is controversial and unclear despite numerous reports. A case report of thymolipoma with cytogenetic analysis is herein presented. The lesion demonstrated a translocation involving the HMGA2 gene on chromosome 12q15, which is seen in two thirds of solitary lipomas. This finding supports the theory that this case of thymolipoma is a neoplasm of thymic fat.