A study from The University of Texas MD Anderson Cancer Center reveals quitting smoking soon after a cancer diagnosis significantly improved survival rates. Published in JAMA Oncology, the study found that smokers who quit within six months of their cancer diagnosis had a 22–26% reduction in cancer-related death compared to those who continued smoking, with the most pronounced benefit in patients who stopped smoking within three months of starting a tobacco treatment program.
The study followed 4,526 cancer patients aged 47–62 who were receiving smoking cessation treatment through MD Anderson’s Tobacco Research and Treatment Program. Treatment involved six to eight counseling sessions and ten to twelve weeks of pharmacotherapy. Participants’ smoking status was monitored over time, with self-reported abstinence confirmed at three-month, six-month, and nine-month intervals.
While smoking cessation at any point post-diagnosis was beneficial, quitting earlier provided the most substantial gains in life expectancy. Over a 15-year period, cancer patients who earlier had the most significant benefits in survival. Specifically, people who stopped smoking within three months saw a 26% drop in their risk of death from cancer. Those who quit within six months had a 22% drop, and those who quit within nine months had a 16% drop.
Patients who began cessation treatment within six months of their cancer diagnosis and successfully abstained from smoking had a nearly doubled median survival rate. Their average survival spanned 3.9 years, compared to 2.1 years for those who continued smoking. Patients who started treatment later—within six months to five years after their diagnosis—also saw benefits, though to a lesser extent. The study also found that the positive impact of quitting smoking shortly after a cancer diagnosis is consistent across multiple cancer types.
“Our research underscores the critical role of early smoking cessation as a key clinical intervention for patients undergoing cancer treatment,” says Paul Cinciripini, PhD, the study’s principal investigator and executive director of MD Anderson’s Tobacco Research and Treatment Program.
The authors highlight that their study emphasizes the need to make tobacco cessation a standard component of cancer care. Following a cancer diagnosis, continued smoking not only increases the risk of cancer progression but also raises the likelihood of developing tobacco-related secondary cancers, such as lung, throat, and esophageal cancer. However, many oncologists do not routinely integrate smoking cessation into their treatment protocols, a gap this study hopes to address.
Previous research has consistently shown the dangers of smoking after a cancer diagnosis. The 2014 Surgeon General’s report on tobacco noted that continued smoking increased the risk of overall mortality by 50% and cancer-specific mortality by 61%. However, until now, studies had not clearly examined the optimal timing for smoking cessation post-diagnosis.
The authors further advocate that smoking cessation should be viewed as an essential first-line intervention that complements conventional cancer treatments. “The results of this study suggest that early entry into tobacco treatment is associated with the best survival outcomes and justifies the need to prioritize tobacco cessation as a core element of first-line cancer care,” they write.