MOLECULAR ALTERATIONS IN ADENOCARCINOMA O F SMALL-BOWEL ASSOCIATED WITH PEUTZ-JEGHERS SYNDROME

The presence of molecular alterations in the c-K-ras and p53 genes in a small bowel adenocarcinoma arising in a case of Peutz-Jeghers syndro me is reported. The absence of mutations at codon 12 and 13 of the c-K -ras gene in the hamartoma and carcinoma indicates that this oncogene does not contribute to its development. On the other hand, p53 protein overexpression was detected in a small proportion (5-10%) of adenocar cinoma cells. Our findings suggest that p53 inactivation occur in late stages of tumour progression.