Usefulness of Prostate Specific Antigen Density in Prostate Cancer Detection among Men with PSA of 4-10 ng/ml

Author(s):

Agbo CA*, Ramyil VM, Dakum NK, Shuaibu SI, Akpayak IC, Ofoha CG, Onowa VE, Nabasu LE and Galam ZZ

Background: Prostate cancer (CaP) is a common malignancy in men and late presentation is still an issue. The discovery of PSA has revolutionized the diagnosis of CaP however has difficulties in discriminating malignant and benign prostatic status especially in patients with grey zone of 4.0-10.0ng/ml. Prostate specific antigen density is useful in this group of individuals. Aims and Objectives: To determine the usefulness of prostate specific antigen density (PSAD) in detection of prostate cancer in native African men with intermediate prostate specific antigen (4.0-10.0ng/ml). Design of the study: It was a cross-sectional, prospective study. Setting: This study took place at the Jos University Teaching Hospital, Urology Division, Department of Surgery, Jos, Nigeria. Materials and Methods: Men who presented at the urology clinic of Jos University Teaching Hospital with intermediate PSA of 4-10ng/ml that had either abnormal DRE findings or PSA density ≥0.15ng/ml² were recruited. Prostate volume was measured using ellipsoid formula through transabdominal ultrasound scan (a GE logic S expert 052128 model ultrasound). The PSA density was calculated by dividing PSA by prostate volume. They subsequently had digitally guided transrectal prostate biopsy. Results were recorded in a structured proforma. Statistical analysis was done using SPSS(R) version 20 (SPSS, IBM, Chicago, IL, USA). Appropriate test statistics were used with p-value < 0.05 considered as significant. Results: Seventy-two (72) men aged 47-99 years were enrolled in the study. The mean age at presentation was 65.4 ± 10.4 years. The cancer prevalence was 26.4%. The commonest age group with cancer was 60-69 years with a mean age of 68.4 years. At a cut-off of 0.15ng/ml2, the cancer detection rate, sensitivity and specificity of PSAD was 51.5%, 89.5% and 69.8% respectively (p <0.001). However, at cut-off of 0.12 ng/ml2, the PSAD had a sensitivity and specificity of 95.0% and 62.0% respectively with AUC 0.84 on ROC (p <0.001). Conclusion: PSAD showed statistical significance in cancer detection (p <0.001) with a detection rate, sensitivity and specificity of 51.5%, 89.5% and 69.8% respectively. It showed a higher sensitivity (95%) at a cut-off of 0.12. PSAD is thus useful in prostate cancer detection among men with PSA 4-10 ng/ml.