Role of estrogens in the secondary hormonal manipulation of hormone refractory prostate cancer.

OBJECTIVE To evaluate the role of Estrogens (Honvan) in the secondary hormonal manipulation of patients with hormone refractory prostate cancer (HRCP). METHODS Twelve patients diagnosed as hormone refractory prostate cancer received intravenous estrogens for six days (Fosfestrol, a synthetic phosphorylated estrogen derivative), followed by a maintenance oral dose of 120 mg thrice daily as second line hormonal treatment. During the treatment they were given deep venous thrombosis prophylaxis. Their stage at initial presentation, primary treatment, mode of androgen ablation, prostate specific antigen (PSA) level, duration of remission prior of HRPC status, PSA doubling time before and after estrogen treatment were recorded. The morbidity and mortality of the treatment was also recorded. A drop in PSA of > 50% was classified as major responder. The drop of < 50% was defined as minor responders. Treatment failure was defined as a rise in PSA > the level prior to the start of treatment. RESULTS The mean age at diagnosis of prostate cancer was 66.6 + 5.4 years (range 57-73). At the time of initial diagnosis only 3 patients (25%) had localized disease and 9 (75%) had metastatic prostate cancer. Six patients each opted for surgical or medical castration (LHRH analogs) as the mode of androgen ablation. The mean initial PSA at diagnosis was 340 + 728.1 ng/ml (range 4.1-2375, Median 94). After development of HRPC, six patients (50%) had major response, four (33%) had minor response to estrogen administration. Two patients (17%) did not respond to estrogens. The mean PSA before receiving Fosfestrol was 60.5 + 82 ng/ml (range 0.013-246). The PSA (nadir) after treatment was 24.3 +/- 33.2 ng/ml (range 0.9-81.3). One patient developed gynaecomastia and one had congestive cardiac failure. Two patients died of non cancer related deaths and one patient died of cancer related death. CONCLUSION Synthetic estrogens are well tolerated, in-expensive agents and could be considered for palliative use against hormone resistant prostate cancer.