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 night time 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.

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