[A CASE THAT TS-1+CDDP THERAPY WAS EFFECTIVE FOR BLADDER PRIMARY SIGNET RING CELL ADENOCARCINOMA]

Since we experienced a case that S-1+Cisplatin (CDDP) therapy was effective for bladder primary signet ring cell adenocarcinoma of pT4N0M0, we report here the time course of its pathophysiology and the treatment of that patient, and discuss the justification of the chemotherapy for the T4 case with the comparison of the previous cases. The present case is a 66 years old man. Because he was aware of the urinary frequency and the sense of incongruity at abdominal region for approximately three months, he visited our hospital for the consultation of his symptoms in July, 2015. The anterior wall showed a torose lesion by cystoscopy from the left sidewall, and we found the histopathology signet ring cell adenocarcinoma after transurethral resection of the bladder tumor. As a result of thorough investigation of thoracic abdominal CT, whole body PET-CT and endoscopy of the upper gastrointestinal tract, we diagnosed it as bladder primary signet ring cell adenocarcinoma with cT3N0M0. Consequently, we tried total cystectomy in August, 2015, however both bladder and pelvic wall were adhered strongly each other; we gave up the total cystectomy and changed the strategy to the urinary diversion by bilateral ureterocutaneous fistula. A biopsy of the adhesion site of the right pelvic wall showed the invasion of the signet ring cell adenocarcinoma, which enabled us to diagnose as pT4bN0M0. Therefore, we performed the chemotherapy with the S-1+CDDP for 12 courses, 16 months from August, 2015 after the surgery. After the initiation of the chemotherapy, the tumor marker was tended to decrease for eight months, but turned to increase thereafter. Because there was no evidence for neither distant nor lymph node metastases of tumor revealed by CT and the MRI, we diagnosed it as Stable Disease at least by CT and MRI examinations for 16 months. The major side-effects were not found during the strengthened chemotherapy without the recurrence until January, 2017. Since this case is very rare, we report the time courses and treatment strategy of a patient with bladder primary signet ring cell adenocarcinoma.