The study performed a retrospective review of 82 African American men who underwent a radical prostatectomy between 2008 and 2017. PSA at diagnosis, prostate volume (PV) estimated by transrectal ultrasound (TRUS), pathologic T Stage (pT), pathologic Gleason Score (pGS), prostate weight at radical prostatectomy, and percentage of the prostate involved with cancer (%PCa) were collected from the record. PSAD was defined as the PSA at the time of surgery divided by the prostate volume obtained during TRUS evaluation. Low-risk prostate cancer was defined as a (1) Stage pT2, pGS 6, and ≤5%PCa and (2) Stage pT2, ≤pGS 3+4, and ≤5%PCa. They then utilized a receiver operator (ROC) curve to assess the ideal PSAD cut-off that identifies low-risk disease in AA men.
The median age for the cohort was 59 years, with median PSA, PV, and PSAD of 8.7 ng/mL,39 ccc , and 0.22 ng/mL/g, respectively. With low risk defined as Stage pT2 + pGS 6 + ≤5%PCa, ROC curve analysis demonstrated a PSAD cut off score of 0.118 ng/mL/gm, which had a sensitivity of 88.0% and specificity of 85.7%. With low risk defined as Stage pT2 + ≤pGS 3+4 + ≤5%PCa, the ROC curve demonstrated a PSAD cut off score of 0.133 ng/mL/gm, which had a sensitivity of 86.1% and specificity of 80.0%. AUC was 0.892 (p<0.001, 95% CI 0.813 - 0.970).
In summary, on a limited sample set PSAD appears to be a good discriminator for low-risk prostate cancer in African American men undergoing radical prostatectomy. A PSAD cut off score of 0.118 ng/mL/gm can be used to predict low risk prostate cancer with good sensitivity and specificity. The lack of a comparator group of non-AA men, and lack of any other oncological measures (biochemical recurrence rates) were significant limitations of the presentation.
Presented By: Kara Babaian, MD, Louisiana State University Shreveport
Written by: Andres F. Correa, Urologic Oncology Fellow , Fox Chase Cancer Center, Philadelphia, PA, Twitter: @UroCorrea, the 2018 AUA Annual Meeting - May 18 - 21, 2018 – San Francisco, CA USA