Comparison Of Prostate-Specific Antigen Ratios - Resolving The Urologist’s Dilemma In Nigerian Men With Prostate Cancer And Benign Prostatic Hyperplasia.

Abstract

Background
Differentiating prostrate diseases using PSA is difficult because PSA changes are not prostate disease-specific which is the Urologist's dilemma in the diagnosis of prostate cancer (PCa) making it necessary to find ways of improving PSA sensitivity.

Objective
The study analyzed the molecular forms of PSA and compared the ability of their ratios to differentiate between BPH and PCa in Nigerian men.

Materials and method

A cross-sectional descriptive multi-centred study that consecutively recruited 120 patients from the urology clinics of Lagos University and University of Calabar Teaching Hospitals in Nigeria. Thirty participants each with BPH and PCa were recruited from each centre over one year. Treatment-naive Patients were histological confirmed for PCa and their Sera analyzed for cPSA, fPSA, and tPSA using WKEA ELISA kits and read off with 2100 STAT FAX microplate reader.

Results
The interquartile ranges were 0.53-0.85 and 0.04- 0.20 with medians of 0.67 and 0.14 for PCa and BPH respectively. p-Value= .001. On the other hand fPSA to tPSA ratios for PCa and BPH had interquartile ranges of 0.03-0.26 (median 0.16) and 0.63-0.88 (median 0.74) respectively. cPSA to total PSA ratio ROC AUC was 0.68 at a cutoff of less than/equal to 33%, with a sensitivity of 57.6% and specificity of 71.2% against fPSA to tPSA ratio which had ROC AUC of 0.66 at a
cutoff of less than/equal to 26% with a sensitivity of 80.3% and specificity of 52.5% to differentiate between PCa and BPH.

Conclusion
Both cPSA to tPSA ratio and fPSA to tPSA ratioare good parameters that improve the early differentiation of PCa from BPH. However, cPSAto tPSA ratio outperformed fPSA to tPSA ratio in terms of specificity and therefore may improve the differentiation of PCa from BPH.