Physician visits and the timing of skeletal-related events among men newly diagnosed with metastatic prostate cancer: A cohort analysis

Introduction

Men diagnosed with metastatic prostate cancer (PCa) are at increased risk for skeletal complications which are associated with significant morbidity and mortality. Although both the urologist and the medical oncologist play important roles in the management of patients with advanced PCa, there is limited information regarding their role in the context of skeletal complications. The current study investigated these relationships among newly diagnosed metastatic patients with PCa.

Methods and materials

This retrospective cohort study used Surveillance, Epidemiology and End Results cancer registry data for incident stage IV metastatic (M1) cases diagnosed from 2000 to 2007 with linked Medicare claims. Postdiagnosis urologist and medical oncologist visits were identified using billing codes. We considered skeletal-related events (SREs) that occurred after the urologist or medical oncologist visit. We used Cox proportional hazards models to examine the relationship between a physician visit and the timing of the first SRE with and without propensity-score matching to account for observable selection.

Results

The sample included 5,572 patients with stage IV M1 prostate cancer. Seventy-six percent of the patients were non-Hispanic White, 16% were non-Hispanic African American, and 8% were of other races; 75% of patients saw a urologist (median time to first visit = 19 days) and 44% saw an oncologist (median = 80 days), whereas 41% experienced at least one SRE (median = 309 days). Covariate-adjusted Cox models showed a longer time to an SRE for patients with only a medical oncologist visit (hazard ratio [HR] = 0.53, 95% CI: 0.45–0.61), only a urologist visit (HR = 0.35, 95% CI: 0.31–0.39) or both a urologist and medical oncologist visit (HR = 0.34, 95% CI: 0.31–0.38), compared to individuals without these visits. Among men with a urologist visit, a medical oncologist visit was not associated with the time to the first SRE (HR = 0.97, 95% CI: 0.90–1.05). Among those without a urologist visit a medical oncologist visit was associated with a longer time to an SRE (HR = 0.54, 95% CI: 0.46–0.64). Results were comparable using propensity-score matched samples.

Conclusion

Among men newly diagnosed with metastatic PCa, 4 of 10 patients experienced an SRE. Patients experienced a delay in skeletal complications when managed by a urologist or a medical oncologist compared to patients who did not see either specialist.