Nerve block cuts hot flashes after breast cancer
NEW YORK (Reuters Health) - Blocking parts of the nervous system that regulate body temperature can reduce hot flashes and improve sleep in survivors of breast cancer, researchers reported on Thursday.
With the experimental nerve blocker therapy, the average number of hot flashes per week fell from about 80 to just 8. Very severe hot flashes were almost totally abolished and a marked drop in nighttime awakenings was also seen, according to a report in the online issue of the Lancet Oncology.
Hot flashes and sleep dysfunction are common in breast cancer survivors, particularly those who use anti-estrogen agents like tamoxifen. Conventional treatments, such as hormone therapy or herbal remedies, have proven either ineffective or have been linked to important side effects.
Blocking the function of "stellate cells" -- star-shaped nerve cell bodies found at the base of the neck -- has been used to treat various conditions for more than 60 years. Dr. Eugene G. Lipov, from Advanced Pain Centers in Hoffman Estates, Illinois, and colleagues hypothesized that this treatment may provide a safe and effective alternative to current therapies used to treat hot flashes and sleep dysfunction in breast cancer survivors.
The new study involved 13 survivors of breast cancer with severe hot flashes and night awakenings who received targeted delivery of a stellate cell blocker. Women were given one block, but during the course of the study they were permitted to have another if they thought that the beneficial effects were waning. Five women had one block and eight had two blocks. Symptoms were assessed one week before treatment and then every week after treatment for 12 weeks.
With treatment, the average number of hot flashes per week fell from 80 to 8, as mentioned, and severe hot flashes virtually disappeared. Night awakenings dropped from 19.5 per week prior to treatment to just 1.4 per week.
The findings of this study suggest that this type of nerve blockade can provide survivors of breast cancer with relief from hot flashes and sleep dysfunction "with few or no side-effects," the investigators conclude.
"Long-term relief of symptoms has the potential to improve overall quality of life and increase compliance with anti-estrogen medications for breast cancer," they say.
SOURCE: The Lancet Oncology, May 15, 2008.
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What breastcancer.org says about this article…
Nerve block cuts hot flashes after breast cancer
The very small study reviewed here found that an experimental nerve blocking therapy, called stellate nerve block, helped relieve hot flashes and sleep problems in 13 women having these side effects because of breast cancer treatment.
Three months after having one or two injections in a group of nerves at the base of the neck (the stellate ganglion), the number of hot flashes the women had dropped by 90%, from about 80 per week to only 8 per week. The number of times they woke up at night dropped about the same amount, from about 20 times per week to less than 2 times per week.
Hormonal therapy medicines are often used in breast cancer treatment to lower the risk of the cancer coming back. Hot flashes and sleep problems are an unpleasant and fairly frequent side affect of hormonal therapy medicines. Bothersome hot flashes also may happen during and after chemotherapy. These side effects can severely affect the quality of life of some women.
The stellate ganglion nerves affect a number of the sensations and experiences your body has, including sweating and blushing. Doctors have known for many years that injecting the stellate nerves with a long-acting anesthetic type of medicine (similar to what dentists use) can ease several troublesome conditions, including extreme facial sweating (hyperhydrosis). So studying a stellate nerve block to ease treatment-related hot flashes makes sense.
Because the stellate nerves have direct connections to the eye, people who have a stellate nerve block often will temporarily have what's called Horner's syndrome. Symptoms of Horner's syndrome include drooping eyelids, narrowed pupils, and loss of the ability to sweat on the side of the face where the nerve block was given. This article didn't mention Horner's syndrome, but some of the women in this study did have these symptoms after they got the nerve block. But the symptoms went away soon afterward. None of the women had any other troubling side effects from the nerve block.
The results of this very small study are quite promising. Still, it's important to remember that the study was VERY small and preliminary. Stellate nerve block shouldn't be used routinely until more is known about the benefits and risks of this approach. The researchers who did this study wanted to see if stellate nerve block would help at all, and if so, how much. Based on this positive experience, stellate nerve block treatment is being studied in a larger group of women. Researchers also are looking at using different approaches to block the stellate nerves.
If you're experiencing troublesome hot flashes and sleep disturbances because of breast cancer treatment, you might want to talk to your doctor about this study. Until more is known, your doctor may not recommend a stellate nerve block. Still, there are other techniques you can use to ease hot flashes. Visit the Breastcancer.org All About Hot Flashes page and the Research News on Menopause and HRT section to learn more about hot flashes, how to avoid them, and how to manage them.