Managing Hot Flashes in Breast Cancer Patients

SAN FRANCISCO—One of the most perplexing issues for healthcare providers caring for breast cancer patients is the management of hot flashes, both natural and induced by treatment, because estrogen replacement therapy is not considered wise.

“The consequences of estrogen deprivation are complex, and its symptoms are significant, debilitating, and can directly impact quality of life,” said Michael Krychman, MD, a gynecologist, certified sex therapist, and cancer survivorship specialist who is executive director of the Southern California Center for Sexual Health and Survivorship Medicine in Newport Beach.

“Comprehensive care of these symptoms will enhance quality of life and increase medication compliance for breast cancer patients,” Krychman said at the 2011 Breast Cancer Symposium, where he shared practice advice on managing hot flashes.

Severe hot flashes are reported by over half of all breast cancer patients and are most common among younger patients and those who take tamoxifen. Young patients tend to be “hit hard” by treatment- induced menopause, not only with the physical symptoms themselves but the idea they are “growing older prematurely,” he noted.

Take a “Conservative Aggressive” Approach First

Treatment options are plentiful, but few are based on evidence. Krychman starts with counseling and education, instructing patients in nonmedication interventions—behavioral, lifestyle, and commonsense approaches—and adding medications as needed.

Observational and nonrandomized studies show benefits for exercise, smoking cessation, cooler ambient temperatures (drinking cold water, air conditioning, fans), the “chillow” (a cooling pillow), and “menopausal pajamas.” Some women respond to dietary interventions: avoiding caffeine, alcohol, and spicy foods and adding basic vitamin and mineral supplements.

Pharmacologic Aids

“Estrogen is not my treatment of choice, though I do prescribe it to a few select patients and follow them closely,” Krychman said. For most patients, he tries the following nonhormonal agents, often in low doses and in combination: antihypertensives (clonidine and methyldopa), megestrol acetate (synthetic progestin), antidepressants, and antiepileptics.

Randomized trials have shown benefits for clonidine and megestrol acetate. A Cochrane review concluded that clonidine, selective serotonin reuptake inhibitors (SSRIs), selective norepinephrine reuptake inhibitors (SNRIs), such as venlafaxine, and gabapentin all have mild-to-moderate effects on reducing hot flashes in breast cancer patients.

“Many women find the SSRI paroxetine very helpful in small doses,” Krychman observed, “but others who may be very sensitive to this class of drugs may have negative sexual side effects. This is concerning because their baseline sexuality may already be in a fragile state due to the breast cancer diagnosis.”

The SSRI escitalopram, however, is not effective in treating hot flashes, he added. There are also concerns that SSRIs interfere with CYP2D6 metabolism, which could affect the efficacy of tamoxifen. “I advise you to continue to exercise caution with regard to the use of potent CYP2D6 inhibitors in women on tamoxifen,” he said.

A newer SNRI, desvenlafaxine, is showing promise and is under review by the US Food and Drug Ad ministration. “Because this medication is nonhormonal and has no effect on the CYP2D6 system, it may offer breast cancer survivors a novel treatment,” he said.

Herbs and Supplements Not Backed by Data

Complementary medicine and alternative therapies are popular, but few are supported by evidence. The Cochrane review did not find efficacy for vitamin E, soy isoflavones, or black cohosh. The American College of Obstetricians and Gynecologists Task Force on Hormone Therapy also examined the scientific evidence for soy, black cohosh, red clover, and Mexican progesterone yam cream and found no significant effects on hot flashes.

Other compounds have been studied even less, and some may “act like estrogens,” which is undesirable, he advised. Altogether, the medical literature does not conclusively support the use of herbs and supplements as a treatment for hot flashes.

Two new compounds are touted as being less estrogenic and possibly of some help. A novel serum estrogen receptor modulator, DT56a (Femarelle, Tofupill) is thought to affect the estrogen receptor only in specific sites and has relieved hot flashes in 75% of users. AUS 131, a synthetic S-equol, is a soy isoflavone that is a nonhormonal selective estrogen receptor agonist being evaluated for hot flashes as well. Efficacy and safety data on these are limited and should “be taken with a grain of salt,” he said.

Mindfulness training and acupuncture are both backed by randomized trials, and may have health effects that extend beyond a reduction in hot flashes, Krychman added