Histopathological changes in human prostatic adenoma following neodymium:YAG laser ablation therapy.

Transurethral laser ablation of the prostate is a procedure currently under evaluation as an alternative to transurethral resection of the prostate in the management of benign prostatic hyperplasia. Removal of prostatic tissue by endoscopic resection or open surgical techniques from 7 patients in whom prostatic laser ablation was previously attempted offered an opportunity to evaluate the sequential effects of such energy upon the human prostate at varying intervals after treatment. A progressive inflammatory and necrotic response, initially akin to that demonstrated after a thermal burn, together with evolving vascular changes within the residual viable prostatic tissue were demonstrated. Our study demonstrates the changes in the human prostate whereby neodymium:YAG laser energy causes a deep coagulative necrosis and arterial thrombosis in the prostatic adenoma. These changes differ significantly from those noted in canine studies. A slower cavitation effect is observed in the human compared with the canine, and this finding mirrors the continuing clinical improvement in voiding parameters with time.