Appendiceal carcinoma mimicking primary bladder cancer.

We report the first case of adenocarcinoma of the appendix invading the bladder. Because invasive bladder cancer was diagnosed intially the pelvis was irradiated preoperatively. At operation a primary appendiceal neoplasm invading the bladder was discovered and a right hemicolectomy and en block partial cystectomy were done. This treatment is recommended for appendiceal adenocarcinoma that invades the bladder.