The complicated post-operative course of a patient who underwent an inguinal herniotomy, has allowed the diagnosis of peritoneal mesothelioma during laparotomy. This highlight the alternatives of an aggressive procedure, such as laparotomy, or a less invasive one, such as laparoscopy. The diagnostic criterion, should be when the clinical course suggests a peritoneal neoplasia; our more invasive technique allowed to perform an operation on the patient's internal organs which should be performed after laparoscopy anyway.