The good news for us is that the survival of men diagnosed with prostate cancer has improved over time. The current 10-year relative survival rate is 99.7%! However, the long survival of men who have prostate cancer raises questions about their risk of a second primary cancer and the need for continued surveillance.

A very large population-based cohort of 441,504 men diagnosed with prostate cancer between 1992 and 2010 was identified from the Surveillance, Epidemiology and End Results Program (SEER) data (SEER13). The standardized incidence ratio (SIR) was calculated as an estimate of the risk of a second primary cancers (malignancy) based on the incidence in the general population.

The analysis of the data showed that men who survived prostate cancer had a lower risk of being diagnosed with another cancer overall compared with the US population. The risks of leukemia and cancers of the oral cavity and pharynx, esophagus, stomach, colon and rectum, liver, gallbladder, pancreas, lung and bronchus, and larynx were significantly lower.

However, prostate cancer survivors had a greater risk of developing bladder, kidney, and endocrine and soft tissue cancers.

Men who received treatment with radiation therapy (external-beam radiation therapy) had long-term increases in their risk of bladder cancer and rectal cancer risk compared with who did not receive radiation.

It was also found that there were significant racial differences in the risk of being diagnosed with a second primary cancer, and the magnitude and direction of these risks depended on tumor type.

BOTTOMLINE
Prostate cancer survivors remain at risk of subsequent cancers, particularly bladder kidney, endocrine and soft tissue cancers. Additionally, race and treatment choice plays an important role for long-term risk.

Prostate cancer survivors must remain vigilant in monitoring themselves as they are at an increased risk for certain second primary cancers.

Cancer. 2014 Sep 1;120(17):2735-41. doi: 10.1002/cncr.28769. Epub 2014 May 19. Davis EJ1, Beebe-Dimmer JL, Yee CL, Cooney KA.

Joel T. Nowak, M.A., M.S.W.