Mayo Clinic and North Central Cancer Treatment Group hot flash studies: a 20-year experience.

Objective: This project was designed to provide an overview of hot flash studies conducted over the past two decades at the Mayo Clinic and in the North Central Cancer Treatment Group.

Design: Prospective clinical trials performed by these investigators are illustrated, described, and discussed.

Results: Ten randomized, controlled (eight placebo controlled), double-blind clinical trials were conducted involving a total of 1,581 women and three placebo-controlled, double-blind clinical trials involving a total of 329 men were conducted. In addition, 14 pilot trials, having involved more than 325 participants to date, were conducted.

Conclusions: Data from the pilot trials have given direction for substances that ought to be further explored in more definitive studies. In men, randomized studies demonstrate that hot flashes are markedly decreased by low doses of megestrol acetate, moderately decreased by gabapentin, but not substantially decreased by clonidine. Results from the randomized trials in women demonstrate that hot flashes are markedly decreased by relatively low doses of progestational agents (megestrol acetate and medroxyprogesterone acetate), moderately decreased by venlafaxine, mildly to moderately decreased by fluoxetine, mildly decreased by clonidine, but not substantially decreased by vitamin E, a soy phytoestrogen product, or black cohosh. Last, the data investigated in these studies support the hypothesis that, for the treatment of hot flashes in women, the results of therapeutic maneuvers are similar regardless of whether the patient has a history of breast cancer and/or is taking tamoxifen.