A Peutz-Jeghers syndrome family associated with sinonasal adenocarcinoma: 28 years follow up report.

Peutz-Jeghers syndrome (PJS) is a rare hereditary disorder characterized by hamartomatous polyps in both of the gastrointestinal tract and mucosal pigmentation. It could increase in risk of intestinal and extra-intestinal neoplasms. We here described three cases of sinonasal polyposis in a PJS family and two developed sinonasal type adenocarcinoma. Genetic study revealed a germline STK11/LKB1 mutation on codon 179 (c.C536G, p.P179R) of exon 4. LOH analysis of the LKB1 locus confirms this to be a deleterious mutation. Sinonasal polyposis with malignant transformation could be encountered in PJS patients. Regular follow-up was recommended for the risk of malignant changes in nasal polyps.