An LH-RH analogue (Zoladex) in the management of carcinoma of the prostate: a preliminary report comparing daily subcutaneous injections with monthly depot injections.

The luteinizing hormone releasing hormone, Zoladex, has been used in three centres, Pontefract, Antwerp and Mistelbach, to treat carcinoma of the prostate. An initial protocol using a soluble daily injection has been followed by a second study employing a monthly administered depot preparation. After an initial stimulation it has been shown that both daily and monthly injections reduce plasma testosterone to castrate levels. Circulating luteinizing hormone levels are also initially stimulated and then suppressed. Treatment toxicity has been minimal and in these short term studies reduction of acid phosphatase and subjective and objective tumour responses have been similar to those expected from effective hormonal therapy of prostatic cancer.