[Peritoneal Cancer Resected as a Greater Omentum Mass-Report of a Patient Surviving Long Term without Recurrence].

We present an interesting case in which a patient diagnosed with primary peritoneal cancer after the resection of a greater omentum mass achieved recurrence-free survival without postoperative systemic chemotherapy. The patient was a 78-yearold woman with no history ofmalignant disease. She underwent abdominal ultrasound at a local clinic, which revealed a mass shadow near the descending colon. She was referred to us in May 2014. Contrast-enhanced abdominal computed tomography showed a homogeneously enhanced soft-tissue mass measuring 94×80×34mm in size in the left lower abdomen, which did not connect to the gastrointestinal tract. In June 2014, a gastrointestinal stromal tumor was suspected, and laparotomy was performed. Laparotomy findings suggested a tumor originating from the greater omentum and no evidence of perifocal invasion. The tumor was resected with the surrounding greater omentum. Pathological examination revealed very poorly differentiated adenocarcinoma, also consistent with ovarian serous adenocarcinoma. No lesions were detected in any other organs by pre- and postoperative examinations, and the patient was diagnosed with primary peritoneal cancer. As the patient refused to receive postoperative systemic chemotherapy, we decided to continue with follow-up only. The patient was alive without recurrence as ofApril 2018.