Light micrograph of an older human prostate gland showing benign glandular hyperplasia, with corpora amylaceae. Prostatic hyperplasia is the most common benign enlargement of the prostate gland. Half of all men have identifiable histology at age 60, and by 85 years the prevalence is about 90%. The increase in size of the prostate inside its capsule exerts pressure on the urethra, which passes through the capsule, resulting in obstruction to urine flow. Magnification:34x.