Prostate-specific antigen, digital rectal examination, and prostate cancer detection: A study based on more than 7000 transrectal ultrasound-guided prostate biopsies in Ghana

Abstract

Purpose of the study

This study aims to determine the role of serum prostate-specific antigen (PSA) levels and digital rectal examination (DRE) in predicting the histological outcomes of prostate biopsies by analyzing a database of over 7000 patients who underwent transrectal ultrasound (TRUS)-guided prostate biopsies.

Methods

We conducted a retrospective analysis of men who underwent TRUS-guided prostate biopsies at Korle Bu Teaching Hospital, a tertiary referral center in Accra, Ghana, from July 2005 to December 2022. The biopsies, which included 10 to 12 core samples, were prompted by PSA levels greater than 4.0 ng/mL, abnormal DRE findings, or both. We then correlated histopathology results with PSA and DRE findings.

Results

Out of 7,338 patients who presented for biopsy, 76.3% were between the ages of 60 and 79. Histology reports were available for 5,289 patients, of whom 2,564 (48.5%) were diagnosed with prostate cancer. Cancer detection rates based on PSA levels were as follows: 21.6% for PSA <4 ng/mL, 21.7% for PSA 4-10 ng/mL, 32.7% for PSA 10-20 ng/mL, 53.0% for PSA 20-50 ng/mL, 71.5% for PSA 50-100 ng/mL, and 92.0% for PSA >100 ng/mL. When DRE findings were classified according to the 2016 TNM System (AJCC 8th Edition) as T1, T2, T3, and T4, cancer detection rates were 26.8%, 51.8%, 87.6%, and 95.7%, respectively. The overall cancer detection rate was significantly higher with abnormal DRE findings (64.6% vs. 26.7%, p < 0.001). Additionally, 78.2% of the detected cancers were high-grade (Gleason score of 7 or more).

Conclusion

This extensive study of Ghanaian men undergoing TRUS biopsies reveals a high prostate cancer detection rate, with nearly 80% of the detected cancers being high-grade. These findings underscore the importance of PSA and DRE in the early detection of prostate cancer and should be considered in patient counseling and discussions regarding the implementation of prostate cancer screening programs in this population.