Mesenteric Leiomyoma Mimicking Recurrence of Rectal Cancer—A Case Report—

Abstract

Leiomyomas of the mesentery are relatively uncommon, with few reports of mesenteric leiomyomas in the literature. A case of a mesenteric leiomyoma is presented. The patient, a 64-year-old man, had undergone surgery for rectal carcinoma one year earlier and was found to have a mesenteric tumor close to the inferior mesenteric artery on the postoperative follow-up. An FDG-PET scan showed hyperaccumulation in the tumor. Preoperatively, the diagnosis was a mesenteric tumor suspected as recurrence of rectal carcinoma. Subsequently, the patient underwent resection of the tumor. Histological examination of the tumor by hematoxylin and eosin staining showed a spindle cell tumor, and immunohistochemical studies were negative for c-kit and CD34, but positive for desmin. The final pathological diagnosis was mesenteric leiomyoma. The differential diagnosis of mesenteric leiomyoma and recurrence of rectal cancer can be challenging due to the similarity in imaging findings. This is a rare case of a mesenteric leiomyoma mimicking recurrence of rectal cancer.