Urologist Practice Affiliation and Intensity-modulated Radiation Therapy for Prostate Cancer in the Elderly

Abstract

Background: Prostate cancer treatment is a significant source of morbidity and spending. Some men with prostate cancer, particularly those with significant health problems, are unlikely to benefit from treatment.

Objective: To assess relationships between financial incentives associated with urologist ownership of radiation facilities and treatment for prostate cancer.

Design, setting, and participants: A retrospective cohort of Medicare beneficiaries with prostate cancer diagnosed between 2010 and 2012. Patients were further classified by their risk of dying from noncancer causes in the 10 yr following their cancer diagnosis by using a mortality model derived from comparable patients known to be cancer-free.

Intervention: Urologists were categorized by their practice affiliation (single-specialty groups by size, multispecialty group) and ownership of a radiation facility.

Outcome measurements and analysis: Use of intensity-modulated radiation therapy (IMRT) and use of any treatment within 1 yr of diagnosis. Generalized estimating equations were used to adjust for patient differences.

Results: Among men with newly diagnosed prostate cancer, use of IMRT ranged from 24% in multispecialty groups to 37% in large urology groups (p<0.001). Patients managed in groups with IMRT ownership (n=5133) were more likely to receive IMRT than those managed by single-specialty groups without ownership (43% vs 30%, p<0.001), regardless of group size. Among patients with a very high risk (> 75%) of noncancer mortality within 10 yr of diagnosis, both IMRT use (42% vs 26%, p<0.001) and overall treatment (53% vs 44%, p<0.001) were more likely in groups with ownership than in those without, respectively.

Conclusions: Urologists practicing in single-specialty groups with an ownership interest in radiation therapy are more likely to treat men with prostate cancer, including those with a high risk of noncancer mortality.

Patient summary: We assessed treatment for prostate cancer among urologists with varying levels of financial incentives favoring intervention. Those with stronger incentives, as determined by ownership interest in a radiation facility, were more likely to treat prostate cancer, even when treatment was unlikely to provide a survival benefit to the patient.

Keywords: Cancer; Prostate; Treatment.