PROSTATIC CAPSULE - A COMPARATIVE-STUDY OF HISTOLOGICAL AND ULTRASONIC APPEARANCES

The histological and transrectal ultrasound (TRUS) appearances at corr esponding sites of the periphery of the prostate gland have been compa red in 30 benign and 27 malignant glands taken at autopsy. In the beni gn series, the histological capsule was frequently absent and correlat ed poorly with the consistent TRUS findings of a regular, well-defined 'ultrasonic capsule'. It is concluded that 'the capsule' should be re placed as a tumour-staging landmark by a more realistic terminology. C arcinoma may be described as intra- or extraprostatic, or confined or unconfined with respect to the gland. In the malignant glands, there w as no correlation between morphologically unconfined cancers and irreg ular or absent ultrasound 'capsule' when corresponding areas were comp ared. This disparity must contribute to an underestimation of tumour e xtent with TRUS.