A Case of Situs Inversus Totalis with Recurrence of Desmoid Tumor after Resection

Abstract

A 72-year-old woman with situs inversus totalis who had undergone hysterectomy presented to us with abdominal distension and anorexia in September 2017. Abdominal computed tomography (CT) revealed an intraperitoneal tumor measuring 52mm in diameter. Positron emission tomography (PET) revealed a maximum standardized uptake value of 3.4 in the tumor. We performed laparoscopically assisted tumor resection, under the differential diagnosis of undifferentiated polymorphic sarcoma, malignant lymphoma, or desmoid tumor. The tumor was located within the jejunal mesentery. Histopathological examination showed spindle-shaped fibroblasts with an abundance of collagen fibers, and the tumor was diagnosed as a desmoid tumor arising from the jejunal mesentery. In 2019 August, a postoperative follow-up CT examination revealed a tumor located in the mesentery, again measuring 52mm in diameter. We suspected recurrence of the desmoid tumor, and performed laparotomy with tumor resection. Histopathology indeed revealed recurrence of the jejunal mesenteric desmoid tumor. While a desmoid tumor in a case of situs inversus totalis is very rare, association of situs inversus totalis with malignant tumors has been reported. Desmoid tumors are also malignant in nature, suggesting that the desmoid tumor in our case was probably a complication of situs inversus totalis. We report a rare case of desmoid tumor with situs inversus totalis.