Primary peritoneal cancer in Lynch syndrome: a clinical-pathologic report of a case and analysis of the literature.

Lynch syndrome is a genetic disease, caused by a germ-line mutation in a mismatch repair gene, related to an increased risk of developing colorectal and extracolonic cancer. Despite that, the incidence of primary peritoneal cancer after adnexectomy remains unknown. We here report a case of primary peritoneal cancer in a woman affected by Lynch syndrome who underwent hysterectomy+salpingo-oophorectomy for endometrial cancer 13 yr before. Morphology and immunophenotype allowed to differentiate peritoneal malignancy from the previously diagnosed endometrial carcinoma. Physicians should be aware of the potential risk of primary peritoneal cancer in women affected by Lynch syndrome, despite previous prophylactic surgery.