Treatment of prostatic cancer with Estracyt (estramustine phosphate).

The experience gained with Estracyt, kindly supplied by AB LEO, Sweden, is reported. On the basis of former data in the literature we only used the drug in estrogen resistant and advanced cases. Estracyt (estramustine phosphate) is a nitrogen mustard derivative of the urethan type, attached to oestradiol-17-phosphate. In histologically verified cases, it was administered in daily doses of 300 mg intravenously for three weeks, followed by maintenance doses of 300 mg a week in tablets for three months. During treatment, liver and bone marrow function was checked systematically. The changes in morphological picture were studied by means of biopsies during and at the end of treatment. In agreement with the data in the literature a favourable effect was observed in estrogen resistant patients, with no toxic effect whatever on the bone marrow. At the same time GOT and GPT and BSP retention examinations demonstrated a hepatotoxic side effect. The pathological values returned to normal after withdrawal of the drug. Histological examinations showed that the tumour cells had changed but failed to disappear after treatment.