Slide 6 of 14

Foible No. 4. Benign Prostatic Hyperplasia (BPH) may affect serum PSA levels in at least 2 ways. First (A), as also indicated in Foible 1, serum PSA levels are in part determined by the volume of epithelial cells present. Large prostate glands generally contain more epithelial cells than small glands and thus contribute more PSA molecules to serum than small glands. Foible 4A, the BPH effect, means that in general, the larger the prostate, the higher the serum PSA level to be expected.