Rajan P et al. -The effect of co-morbidity on prostate cancer (PCa)–specific mortality was determined.In the current study, co-morbidities were shown to effect all cause–mortality, but not PCa-specific–mortality, after adjusting for patient and tumor characteristics, and treatment type. Whether radical prostatectomy or radical radiotherapy, co-morbidities did not significantly affect PCa-specific mortality.