Correlation of digital rectal examination and serum prostate-specific antigen levels for detection of prostate cancer: Retrospective analysis results from a tertiary care urology center.

ABSTRACT

Objective: The objective of our study was to evaluate the detection rate of prostate cancer by digital rectal examination (DRE) and serum prostate-specific antigen (PSA) levels followed by standard 12-core transrectal ultrasound (TRUS)-guided prostate biopsy. Materials and Methods: After screening of patients presenting with lower urinary tract symptoms (LUTS) using DRE and serum PSA level, we enrolled patients for TRUS-guided 12-core prostate biopsy. Indications included PSA level ≥4 ng/ml and/or suspicious DRE findings. A retrospective analysis was done to find out the correlation between suspicious rectal examination and various serum PSA levels in detection of cancer prostate. Results: A total of 847 patients were screened for cancer prostate during our study period (May 2012-February 2020). Among them, 823 patients who underwent prostate biopsy were analyzed. Prostate cancer was detected in 330 cases (40.09%). Mean age of patient (years) with and without prostate cancer was 66.25 ± 9.45 and 64.3 ± 8.96 years, respectively. Median value of serum PSA in patients positive for cancer was 33 ± 260 ng/ml compared to patients without cancer, who had a median value of 9 ± 64 ng/ml (P-value of <0.0001). The detection rate of cancer based on suspicious DRE findings irrespective of PSA was 52.18% (251/481), compared to 45.46% (311/684) using a PSA cut-off of ≥4.0 ng/ml alone. Among 330 patients with positive biopsy, 19 (5.75%) had a PSA level <4 ng/ml and they were identified based on suspicious DRE alone. Conclusion: Suspicious DRE was significantly associated with detection of prostate cancer across all PSA levels. Patients with PSA <4 can harbor prostate malignancy and such cases can be detected by use of DRE in screening of all patients with LUTS.