A case of granular cell tumor of the bladder successfully managed with extraperitoneal laparoscopic surgery

Granular cell tumor is a benign neoplasm which frequently occurs in the oral cavity, skin, and subcutaneous tissue. Granular cell tumor of the bladder is an extremely rare disease, and only nine cases have been reported. We present here an additional case of granular cell tumor occurring in the bladder. Unlike the other tumors reported, this tumor extruded into the Retzius' cavity. Therefore, the tumor was successfully excised through extraperitoneal laparoscopic surgery. The patient was free from recurrence 40 months after surgery. The small tumor located in Retzius' cavity could be managed with extraperitoneal laparoscopic surgery.