Gerber, G.S., Zagaja, G.P., Ray, P.S., & Rukstalis, D.B. (2000). Transdermal estrogen in the treatment of hot flushes in men with prostate cancer. Urology, 55, 97–101.

The study evaluated the efficacy of transdermal estrogen in men in moderating hot flashes after hormonal therapy for prostate cancer.

• Intervention: Estrogen patch
  • Low dose (0.05 mg)
  • High dose (0.5 mg)
• Description of protocol:
  • Daily log maintained
  • Participants randomized to low-dose or high-dose of transdermal estrogen, then switched after four week washout to other dose

The study enrolled 12 men with advanced prostate cancer who were receiving leuprolide injections every one or three months. They were experiencing at least three hot flush episodes daily for at least three months.

This was a randomized, multi-dose, crossover trial.

Treatment response was assessed indaily logs. Questionnaires were completed every four weeks, including visual analog assessment. Serum luteinizing hormone (LH), follicle stimulating hormone (FSH), testosterone, and estradiol levels were taken every four weeks.

Key outcomes of the study included:

• Significant reduction in overall severity of hot flushes with both the low-dose and high-dose patches in 10 of the 12 men (83%) 
• Significant decrease in daily frequency of hot flushes with high-dose patch 
• Overall moderate to major improvement in symptoms at both doses (p = 0.04)
• FSH levels decreased significantly with both doses; estradiol levels increased with both doses. No significant change in serum testosterone or LH.

Study limitations included small sample size, absence of placebo arm, short duration.