Breast cancer survivors who quit smoking after their diagnosis reduced their risk for death 33%, according to findings from a population-based prospective observational study.
The 2014 Report of the Surgeon General on the consequences of smoking suggested that there may be a relationship between breast cancer and smoking. Further, previous research indicated that risk for breast cancer in smokers was affected by the initiation of a smoking habit and how long a patient had been smoking.
“Our study shows the consequences facing both active and former smokers with a history of breast cancer,” Michael N. Passarelli, PhD, MPH, MS, cancer epidemiologist at University of California San Francisco School of Medicine, said in a press release. “About one in 10 breast cancer survivors smoke after their diagnosis. For them, these results should provide additional motivation to quit.”
Passarelli and colleagues used data from the Collaborative Breast Cancer and Women’s Longevity Study to evaluate the association between smoking status — before and after diagnosis — and mortality in 20,691 women aged 20 to 79 years who were diagnosed between 1988 and 2008. Researchers recontacted a subset of 4,562 women from that population at a median of 6 years following diagnosis.
During a median of 12 years, 6,778 women had died, including 2,894 who died of breast cancer.
Women who were active smokers 1 year prior to their diagnosis (20%) were more likely to die of breast cancer (HR = 1.25; 95% CI, 1.13-1.37), cardiovascular disease (HR = 2.08; 95% CI, 1.8-2.41), respiratory cancer (HR = 14.48; 95% CI, 9.89-21.21) or other respiratory disease (HR = 6.02; 95% CI, 4.55-7.97) than never smokers.
The 10% of the women who continued to smoke after diagnosis were more likely to die of breast cancer than never smokers (HR = 1.72; 95% CI, 1.13-2.6).
Women who quit smoking after diagnosis had a 33% (HR = 0.67; 95% CI, 0.38-1.19) reduced risk for dying of breast cancer and a 61% (HR = 0.39; 95% CI, 0.16-0.95) reduced risk for dying of respiratory cancer when compared with women who continued to smoke after diagnosis.
“Smoking cessation programs should be considered part of cancer therapy,” Passarelli said in the release. “Recent policy statements from leading research and clinical organizations are now urging oncologists to be as aggressive in getting their patients to stop smoking as they are in treating the cancer.” – by Anthony SanFilippo
Disclosure: Passarelli reports no relevant financial disclosures. One other researcher reports holding use patents for the chemopreventive use of calcium and the colorectal chemopreventive use of aspirin.