RET ONCOGENE ACTIVATION IN PAPILLARY THYROID-CARCINOMA - PREVALENCE AND IMPLICATION ON THE HISTOLOGICAL PARAMETERS

The Ref proto-oncogene is known to be rearranged in papillary carcinom a of the thyroid. The aim of this study was to investigate the in situ expression of Ret mRNA in thyroid tumors. Formalin-fixed, paraffin-em bedded tissue specimens from 45 thyroid lesions were examined by in si tu hybridization using manual capillary action technology (MicroProbe Staining System) and a 52-base synthetic biotmylated oligonucleotide p robe complementary to the tyrosine-kinase domain of Ret proto-oncogene . The clinicopathological features of these patients with thyroid lesi ons also were noted. Ret was noted in 17 (43%) of 40 papillary carcino mas. In contrast, none of the three follicular carcinomas, follicular adenoma, nodular hyperplasia, and normal thyroids, showed evidence of Ref mRNA Our results showed that, in papillary thyroid carcinoma, ther e is an important role of Ret activation. The Ret staining could be a useful marker for papillary carcinoma. HUM PATHOL 29:565-568. Copyrigh t (C) 1998 by W.B. Saunders Company.