A case of mesenteric desmoid tumor of the small intestine occurring during hormone therapy for prostate cancer

Abstract

A 54-year-old man was being treated with hormone therapy for prostate cancer with bone metastasis. On abdominal CT done to ascertain the effectiveness of treatment, a mesenteric tumor of the small intestine was found incidentally. Since the a tumor was not detected prior to treatment, lymph node metastasis of the prostate cancer was suspected ; the hormone therapy was continued. On CT done 3 months later, an enlarged mesenteric tumor and no bone metastasis changes were noted. It was thought that the tumor was not a lymph node metastasis but unrelated mesenteric tumor. Gastrointestinal fiberscopy did not identify any malignant tumors. Though the origin was unknown, surgery was performed under a presumptive diagnosis of intra-abdominal tumor such as a mesenchymal tumor. On pathology, a desmoid tumor was diagnosed. The patient had no family history of familial adenomatous polyposis or previous abdominal surgery. A hormonal imbalance resulting from the hormone therapy given for prostate cancer was suspected of having contributed to the occurrence and growing of the mesenteric tumor.