Primary signet‐ring cell carcinoma of the urinary bladder inducing renal failure

A case of primary signet-ring cell carcinoma of the urinary bladder that was found to have induced renal failure is the second such case reported in the world. Primary signet-ring cell carcinoma of the urinary bladder is a rare histologic variant of adenocarcinoma. The patient died of distant metastasis 8 months after undergoing total cystectomy. The neoplasm had a high stage at diagnosis, so the prognosis was very poor. To improve the prognosis, earlier diagnosis and establishing a regimen of chemotherapy is necessary.