TOPLINE:

In a cohort of 13,282 patients with cancer, those who quit smoking within 6 months of their index visit showed nearly double the survival rate compared with those who continued smoking. Only 22.1% of current smokers successfully quit, but those who did demonstrated significantly improved overall survival across all cancer stages.

METHODOLOGY:

• Approximately 25% of patients with cancer report smoking at diagnosis, with up to 58% continuing to smoke during treatment. Evidence suggests that clinicians may be less likely to offer smoking cessation support to patients with advanced-stage cancer, often due to misconceptions about the benefits of quitting at this stage.
• Researchers conducted an observational cohort study of 13,282 patients diagnosed with cancer who were evaluated in outpatient oncology clinics between June and December 2018. The study included 2258 patients with tobacco-related head, neck, respiratory, or esophageal cancer; of those patients, 1412 had lung cancer. An additional 2806 patients had tobacco-related cervical, pancreatic, liver, stomach, or urinary cancer. The remaining participants had a solid tumor cancer not related to tobacco use (6326), a hematologic cancer that was related to tobacco use (66), or a hematologic cancer that was unrelated to tobacco use (1826).
• Analysis included prospective follow-up of smoking cessation rates over 6 months, with smoking status documented at each outpatient visit by the oncology care team.
• Investigators assessed the impact of index-visit smoking status and smoking cessation within 6 months on 2-year overall survival using multivariable Cox proportional hazards models and the Kaplan-Meier method.
• Patient population comprised 49.5% never smokers, 37.6% previous smokers, and 13.0% current smokers, with most patients having nontobacco-related malignancies and advanced-stage (III/IV) disease.

TAKEAWAY:

• Patients who continued smoking showed a significantly higher risk for all-cause mortality (adjusted hazard ratio [aHR], 1.97; 95% CI, 1.53-2.55) than those who quit smoking.
• Current smokers at the index visit demonstrated increased mortality risk (aHR, 1.35; 95% CI, 1.20-1.53) compared with never smokers, while previous smokers also showed elevated risk (aHR, 1.13; 95% CI, 1.03-1.25).
• Among patients with advanced-stage (III or IV) cancer, continued smoking was associated with doubled mortality risk (aHR, 2.11; 95% CI, 1.60-2.79).
• Estimated adjusted survival probabilities at 2 years were higher for never smokers (81.4%) than for previous smokers (79.4%) and current smokers (76.4%).

IN PRACTICE:

“Smoking cessation support should be provided to all cancer survivors who smoke, regardless of cancer type or stage, and should be viewed as an integral component of comprehensive oncology care,” wrote the authors of the study.

SOURCE:

The study was led by Steven Tohmasi, MD, MPHS, Washington University School of Medicine in St. Louis. It was published online in the Journal of the National Comprehensive Cancer Network.

LIMITATIONS:

According to the authors, tobacco use was not confirmed through biochemical testing, which may have led to misclassification of smoking status. The researchers note that changes in smoking status may have been missed for patients not seen in follow-up between January and June 2019, those who quit smoking at a later time, or those lost to follow-up. Additionally, the observed survival benefit associated with smoking cessation may be partially influenced by unmeasured patient-level factors, such as other healthy lifestyle habits, greater treatment adherence, or survival bias.

DISCLOSURES:

The study received support from the National Cancer Institute, National Institutes of Health, US Department of Defense Lung Cancer Research Program, and the Alvin J. Siteman Cancer Center Siteman Investment Program. The authors disclosed that they did not receive any financial consideration from any person or organization to support the preparation, analysis, results, or discussion of this article.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.