Long-term urinary adverse effects of pelvic radiotherapy

Radiation for tumors arising in the pelvis has been utilized for over a 100 years. Adverse effects (AEs) of radiotherapy (RT) continue to accumulate with time and are reported to show decades after treatment. The benefit of RT for pelvic tumors is well described as is their acute AEs. Late AEs are less well described. The burden of treatment for the late AEs is large given the high utilization of RT.

For prostate cancer, 37% of patients will receive radiation during the first 6 months after diagnosis. Low-and high-grade AEs are reported to occur in 20-43 and 5-13%, respectively, with a median follow-up of ~60 months. For bladder cancer, the grade 2 and grade 3 late AEs occur in 18-27 and 6-17% with a median follow-up of 29-76 months. For cervical cancer, the risk of low-grade AEs following radiation can be as high as 28%. High-grade AEs occur in about 8% at 3 years and 14.4% at 20 years or ~0.34% per year. Radiation AEs appear to be less common or at least less well studied after radiation for rectal and endometrial cancers.

Properly delineating the rate of long-term AEs after pelvic RT is instrumental to counseling patients about their options for cancer treatment. Further studies are needed that are powered to specifically evaluate long-term AEs.