KLINEFELTERS-SYNDROME ASSOCIATED WITH TESTICULAR MICROLITHIASIS AND MEDIASTINAL GERM-CELL NEOPLASM

Klinefelter's syndrome is a genetic disorder of male sexual differenti ation characterized by an XXY karyotype. Although considered a benign condition, it is associated with several types of malignancies, includ ing mediastinal germ-cell neoplasm. In addition, Klinefelter's syndrom e has been rarely associated with testicular microlithiasis. Whereas p atients with Klinefelter's syndrome have an increased incidence of ext ragonadal germ-cell neoplasms, patients with testicular microlithiasis have a predisposition to testicular germ-cell neoplasms. To our knowl edge, an extragonadal germ-cell neoplasm has not been previously descr ibed in association with testicular microlithiasis. We present a patie nt with 2 unusual conditions, both of which are independently associat ed with Klinefelter's syndrome: mediastinal germ-cell neoplasm and tes ticular microlithiasis. (C) 1997 John Wiley & Sons, Inc.