Multiple primary malignant neoplasms: case report and a comprehensive review of the literature.

A case is presented of an elderly patient with synchronous ureteral/bladder/urethral transitional cell carcinoma and prostatic adenocarcinoma. In a subsequent review of 1,104,269 cancer patients in the literature, the reported prevalence of multiple primary malignant neoplasms (MPMN) varies between 0.734% and 11.7%. It appears that MPMN might occur more frequently than can be explained on the basis of random chance. As expected, the incidence of developing MPMN is noted to rise with increasing age. In addition, the preponderance of men with MPMN is caused primarily by the high frequency of prostatic cancer. Current studies and research need to address the potential of older cancer patients being at higher risk of second primaries.