Metastasic Prostate Cancer: Predictive Factors of Earlier Progression to Castration-Resistance.

Introduction: Prostate cancer (PCa) can progress to the lethal phenotype of metastatic castration resistance (mCRPC), either from initially localized disease or metastatic cancer. New drugs improving overall survival are now the cornerstone of treatment. Nevertheless, there are no defined sequences or established timing to initiate or discontinue treatments; besides, not all patients end in CRPC or reach this stage at the same time.

Objective: To evaluate characteristics of patients who progress to mCRPC and establish an association with time to mCRPC diagnosis.

Material And Methods: Retrospective, descriptive and observational study of 35 mCRPC patients, performed from 2013 to 2017. Variables analyzed were age, Gleason score and prostate-specific antigen (PSA) at diagnosis, initial stage, response time to androgen deprivation therapy (ADT), PSA nadir on ADT and time until mCRPC progression. Statistical analysis comparing variables with time to mCRPC diagnosis was performed.

Results: Average age at diagnosis was 68.9 years; PSA values were classified into 3 categories: <20 ng/ml, 20-50 and >50. Gleason score was 7 in 50%, and 8-9 in the rest. Tumor was initially localized in 46% of the patients and metastatic in the rest. PSA nadir on ADT was <1 ng/ml in 67%. Average time to androgen deprivation: 5.5 years, time to mCRPC diagnosis: 6.9 years. Significant associations between time to mCRPC and time of androgen deprivation, PSA nadir during ADT and stage at diagnosis were found.

Conclusion: Response time to ADT <1 year, PSA nadir value >5 ng/ml during treatment and metastatic stage at diagnosis were associated with earlier progression to mCRPC.