Mucinous carcinoma of the colon in a 16-year-old Turkish boy with Bloom syndrome: Cytogenetic, histopathologic, TP53 gene and protein expression studies

A 17-year-old Turkish boy with Bloom syndrome (BS) developed mucinous carci noma of the transverse colon. He was followed from 2 to 17 years of age. In creased sister chromatid exchanges (SCE) were observed, and he was diagnose d with BS at the age of 7. Sun-sensitive skin lesions were examined by skin biopsy, and histopathological studies of these lesions were done. During t he follow-up period, an intraabdominal mass at the transverse colon was fou nd, and mucinous carcinoma of colon was diagnosed at the age of 16. We exam ined TP53 protein expression from paraffin-embedded colon tissue of the pat ient with an immunohistochemical method. Polymerase chain reaction products of exons 4-9 of the TP53 gene were examined by SSCP. No evidence of overex pression of TP53 protein or mutations of the TP53 gene uas observed. The pa tient in this report is the first case with a mucinous carcinoma of colon d iagnosed at an early age in the Bloom Syndrome Registry. Based on our resul ts, carcinoma of the colon in BS patient may occur earlier than 35 years of age and the TP53 gene may not be directly related to carcinoma in Bloom sy ndrome. (C) Elsevier Science Inc. 1999. All rights reserved.