Use of additional treatment for prostate cancer after radical prostatectomy, radiation therapy, androgen deprivation, or watchful waiting

OBJECTIVE. To examine how the use of additional treatment for prostate cancer differs as a function of the initial therapy (radical prostatectomy [RP], radiation therapy [RT], androgen deprivation therapy [ADT], or watchful waiting [WW]) for men with non-metastatic prostate cancer. MATERIAL AND METHODS. A dataset was created that combined information from the Surveillance, Epidemiology, and End Results program and Medicare claims for hospital and physician services. To identify patients receiving additional cancer treatment, we searched the claims for the presence of RP, RT (palliative radiation not included), or ADT. RESULTS. The study population consisted of 12 711 patients: as initial treatment, 3940 (31.0%) had RP, 3950 (31.1%) RT, 1209 (9.5%) ADT, and 3612 (28.4%) WW. The RP group had a less favorable distribution of tumor differentiation than the RT group. Only 54.6% of men who had initial RP had localized cancer. In men who had initial RP, 8.1% had RT and 12.4% ADT during the follow-up period, which was 6-66 months after the initial therapy ended. Among patients who had initial RT or WW, 22.8% and 22.1%, respectively had ADT during the follow-up period. CONCLUSION. Older American men with prostate cancer who are initially treated with RT or simply observed (WW) are more likely than men who undergo RP to receive ADT as a follow-up treatment.