Practice patterns and predictors of followup imaging after a negative bone scan in men with castration resistant prostate cancer: Results from the SEARCH database

Purpose: We investigated imaging practice patterns in men with nonmetastatic (M0) castration resistant prostate cancer.Materials and Methods: We analyzed data on 247 patients with documented M0 CRPC from the SEARCH database. Patients were selected regardless of primary treatment modality and all had a negative bone scan after a castration resistant prostate cancer diagnosis. Cox models were used to test associations of time to a second imaging test with several demographic and clinical factors.Results: During a median followup of 29.0 months (IQR 12.9–43.5) after a post-castration resistant prostate cancer bone scan was negative, 190 patients (77%) underwent a second imaging test. On univariable analysis patients with higher prostate specific antigen (HR 1.13, p = 0.016), shorter prostate specific antigen doubling time (HR 0.79, p <0.001) and faster prostate specific antigen velocity (HR 1.01, p <0.001) were more likely to undergo a second imaging test. Treatment center was also a significant predictor of...