Structure and per-rectal ultrasonography of prostatic disease using cadaver specimens

One hundred cadaver prostates were examined by per-rectal ultrasound and the findings correlated with the microradiographic and histopathological features of whole sections taken at the levels of scanning. The normal gland consists of both periurethral muscle and glands. The periurethral muscle has little structure on microradiography and is therefore hypoechoic (low amplitude echoes) on ultrasound scanning. The gland itself, both central and peripheral zones, has a lattice appearance on microradiography (reticular structure) and therefore produces mid-range amplitude echoes on ultrasound. Benign hypertrophy develops at the edge of the periurethral muscle and is microadenomatous in structure. This produces mid-range amplitude echoes which are coarser than in the normal gland. Associated calcification has a characteristic distribution around the adenomas. Cancer produces an amorphous structure resulting in loss of ultrasonic echoes (hypoechoic). In a few cancers irregular calcification is present, resulting in high echoes in the ultrasound scan (hyperechoic) which are not in the typical benign distribution. The internal structure of the prostate was therefore demonstrated in its histopathological states by the technique of microradiography and seen to relate to its representation by ultrasound.