PSA surveillance following radical prostatectomy: What we know and why it matters

Abstract

Disease recurrence is common after initial therapy for prostate cancer, but little is known about how well men receive follow-up surveillance after initial treatment or how patterns of follow-up care may influence choice of initial treatment. The overall objectives of this dissertation were (1): to examine patterns of prostate-specific antigen (PSA) test receipt among elderly men treated with radical prostatectomy for non-metastatic prostate cancer, (2): to validate the radiation therapy variable in Surveillance, Epidemiology, and End Result (SEER) data by comparing treatment receipt with Medicare claims, and (3): to compare through a decision model a "wait and see" approach to radiation therapy in which radiation therapy is initiated only after evidence of disease recurrence to an approach of treating all qualifying men with radiation therapy adjuvant to surgery. This dissertation used population-based SEER-Medicare data to examine the first two aims. The decision model was constructed as a Markov cohort model and populated with data from clinical trials, retrospective studies, surveys, and Medicare fee schedules.

Time from treatment was the dominant factor in predicting whether a man received a PSA surveillance test in a given year following surgery. In all men, test receipt decreased as time from surgery increased. I also found some evidence of racial/ethnic disparities in test receipt as well as evidence that test receipt is influenced by access to care and social support. I found that although there is some disagreement across SEER and Medicare in terms of documentation of adjuvant radiation therapy (ART) receipt, overall agreement is very high. This lends support to previous studies using SEER alone to study ART. The results from the decision model suggest that most men will benefit more from a wait and see approach to radiation therapy than ART. However, if men do not receive appropriate PSA surveillance testing, ART may be a better option. This research highlights the need for long-term follow-up care plans for men treated with radical prostatectomy for prostate cancer.