New research published in the British Journal of Cancer concluded that common treatment for breast cancer works less well in patients who smoke, compared to non-smokers. The study followed 1,016 breast cancer patients in southern Sweden diagnosed between 2002 and 2012. At the time of surgery they were asked whether they were smokers or non-smokers and about one in five said they were a regular smoker or social smoker. The impact of smoking was evaluated based upon type of breast cancer treatment received after surgery.
Results showed that women over age 50 treated with aromatase inhibitors, were affected by smoking. The aromatase treatment prevents the body from generating estrogen in fatty tissue and thereby reduces the risk of recurrence in women with estrogen-receptive positive breast cancer. This treatment worked significantly better in non-smokers. Researchers said “Smokers who were treated with aromatase inhibitors had a three times higher risk of recurrence of breast cancer compared with the non-smokers who got the same treatment.” They also found that “the smokers also had an increased risk of dying, either from the breast cancer or from other illnesses, during the time we followed them.”
However, the researchers found little or no difference between smokers and non-smokers treated with the drug tamoxifen, radiotherapy, or chemotherapy. Despite telling patients of the importance of stopping smoking only ten perce of the 206 smokers stopped in the first year after surgery. Researchers said the number of smokers who stopper was too small to determine if that made a difference in their future risk. More research is needed.