Simple numerical chromosome aberrations characterize pituitary adenomas

Although pituitary adenomas are among the most frequent intracranial neopla sms, only very few have been cytogenetically analyzed. We have short-term c ultured and karyotyped 28 consecutive pituitary adenomas (16 clinically non functioning adenomas and 12 clinically functioning adenomas), finding a nor mal karyotype in 22, whereas 6 had clonal chromosome aberrations (5 nonfunc tioning pituitary adenomas and 1 prolactinoma). The abnormal karyotypes wer e relatively simple. Most anomalies were numerical, with a structural rearr angement, t(6;19), being found in only one tumor. The most common aberratio ns were trisomy 7 (3 adenomas), trisomy 9 (2 adenomas), trisomy 12 (2 adeno mas), trisomy 20 (2 adenomas) and loss and gain in 2 separate clones of one X chromosome (2 adenomas). (C) Elsevier Science Inc., 1999 All rights rese rved.