Incidental finding of a malignant peritoneal mesothelioma in an inguinal hernia sac: report of a case.

We report the case of a 46-year-old female who underwent a routine operation of herniorraphy for a right inguinal hernia. Physical findings revealed a moveable tender mass in the right lower inguinal area. Pathological examination revealed a mass with multiple nodules scattered in the inguinal hernia sac. The histological features of these nodules were compatible with malignant peritoneal mesothelioma (MPM). The incidental finding of MPM in the inguinal hernia sac is very rare. The incidence of this neoplasm is 2-2.6 cases per million annually, and the prognosis is very poor.