Role of PSA Kinetics in Hormone-refractory Prostate Cancer

Objective: To demonstrate the predictive effect of PSA derivatives and time markers that is prostate-specific antigen (PSA) doubling time (PSADT) and PSA velocity (PSAV) on survival in men with hormone-refractory prostate cancer (HRPCa). Study Design: Descriptive, analytical study. Place and Duration of Study: Department of Urology, Erciyes University, Faculty of Medicine, Kayseri, Turkey, between 2012 and 2020. Methodology: One hundred patients, who were treated with prostate cancer, were subjected. The PSA values were noted, nadir PSA values were detected, times to nadir PSA, HRPCa, and follow-up times were recorded. PSADT and PSAV were calculated. The relationships between the groups were analyzed. Kaplan-Meier curves were used to estimate overall survival between the groups. Results: The patients were grouped according to the mean PSADT, median PSAV, median nadir PSA, and mean time to HRPCA. The survival of those with high PSADT, low PSAV and low nadir PSA were found to be significantly longer (p=0.006, p<0.001, p<0.001). High PSAV was also associated with significantly increased PSA, nadir PSA and death (p<0 001p=0.47, and p<0.001, p=0.52, respectively). The survival of those with a longer time to HPRCa was found to be significantly longer (p<0.001). There was no statistically significant difference in terms of survival between patients who received chemotherapy after HRPCa and those who did not (p=0.477). PSAV (p=0.007 HR: 1.004 95% CI: 1.001 - 1.007), bone metastasis at diagnosis (p=0.001 HR: 0.357 95% CI: 0.197 - 0.645) and time to HRPCa development (p=0.001 HR: 0.936 95% CI: 0.900 - 0.974) were significantly effective to the survival. Conclusion: PSADT, PSAV, and nadir PSA serve as independent prognostic markers for survival in patients with HRPCa. These three PSA derived calculation products, with the help of other parameters, could work as prognostic factors, and help clinicians predict survival in men with HRPCa