Transdermal oestrogen therapy as a second-line hormonal intervention in prostate cancer: a bad experience

OBJECTIVE: To compare transdermal oestrogen with oral diethylstilbestrol (DES) as a second- or third-line hormonal therapy in the treatment of prostate cancer. PATIENTS AND METHODS: In all, 32 assessable patients who, having already had a relapse on at least one line of hormonal therapy, received transdermal oestrogen therapy as an alternative to oral DES, when DES became unavailable. RESULTS: Whereas DES had controlled the prostate-specific antigen (PSA) level for a median of 29 weeks in a group of 15 patients in remission, all but one had an increase in PSA level (median 86% increase above the starting PSA level) within a median of 8 weeks after introducing transdermal therapy. This increase was reversed in seven of the 12 patients who recommenced DES therapy. CONCLUSION: Although the use of transdermal oestrogen is currently attracting enthusiasm as a first-line treatment for prostate cancer, these results show that for second- or third-line therapy further cautious research with careful monitoring is necessary.