Ureteral rupture with retroperitoneal urinoma caused by peritoneal metastases of gastric cancer.

We describe the rare case of a patient with ureteric rupture during systemic drug treatment for peritoneal metastases of gastric cancer, who underwent double-J stent placement. A 66-year-old man with gastric cancer was referred to the authors' hospital. Esophagogastroduodenoscopy showed an irregular elevated lesion with thickened gastric folds, and biopsy specimens revealed a poorly differentiated adenocarcinoma. Abdominal contrast-enhanced computed tomography (CT) revealed extensive wall thickening with homogeneous enhancement of the stomach, enlarged lymph nodes in the perigastric area, and nodules in the peritoneal cavity, suggesting peritoneal metastases. The clinical diagnosis was cT4N2M1 with peritoneal metastases, and the patient received chemotherapy (S-1 plus oxaliplatin). After six courses of chemotherapy, the patient presented to the emergency outpatient department with a complaint of acute severe pain in the left lower back. Emergency abdominal contrast-enhanced CT showed extravasation of the contrast medium from the left upper ureter in the periureter area along with the retroperitoneum, and there was no mass lesion or stone in the kidney, ureter, or bladder. A double-J stent was placed under cystoscopic guidance, and no resistance was felt when the stent was inserted. The patient's postprocedural course was uneventful, and he received ramucirumab in combination with paclitaxel after double-J stent placement. However, 2 months later, systemic drug treatment was discontinued because of loss of appetite and increased general fatigue and changed to the best supportive care. His general condition gradually deteriorated, and he died 3 months after the ureteral rupture. Prompt interventions, including retrograde placement of ureteral stents with concurrent use of antibiotics, will reduce mortality and morbidity in this rare entity.