Which feature best distinguishes prostate-specific antigen (PSA) elevation in benign prostatic hyperplasia (BPH) from prostate cancer in a 65-year-old Indian male with PSA 8 ng/mL?

Explanation

## PSA Elevation: BPH vs. Prostate Cancer **Key Point:** PSA density (PSA concentration per unit prostate volume) is the most specific discriminator. High density (>0.15) suggests cancer; low density suggests benign hypertrophy. | Feature | BPH | Prostate Cancer | Discriminatory Value | |---------|-----|-----------------|----------------------| | **PSA density >0.15** | Rare | Common (70–80%) | **Best discriminator** | | **Absolute PSA >10** | Common | Common | Non-specific | | **PSA velocity >0.75** | Slow rise | Rapid rise | Moderately useful | | **PSA >4 ng/mL** | Frequent | Frequent | Poor specificity | **High-Yield:** PSA density corrects for prostate size. Large benign prostates produce more PSA; cancer produces PSA disproportionate to gland size. A PSA of 8 ng/mL in a 50 cm³ gland (density 0.16) suggests cancer; in a 100 cm³ gland (density 0.08) suggests BPH. **Clinical Pearl:** PSA density requires transrectal ultrasound (TRUS) measurement of prostate volume. PSA velocity requires serial measurements over ≥1.5 years and is less reliable in a single cross-sectional assessment.