A recent study conducted by Harvard has observed that people who quit smoking before their lung cancer diagnoses have a much better chance of surviving. Compared to those that never smoked, current smokers being treated for non-small-cell lung cancer (NSCLC) have a 68 percent higher mortality rate. Former smokers, on the other hand, had a 26 percent higher mortality rate as compared to those who never smoked at all.
Moreover, the study found that the length of time a patient had refrained from smoking before their lung cancerdiagnosis had a direct impact on their odds of survival. The findings, published in JAMA Network Open, shed light on the vital importance of smoking cessation in the context of lung cancer.
Professor of environmental genetics at the Harvard T.H. Chan School of Public Health in Boston, and senior author, David Christiani, MD, MPH, explains that these findings prove that it’s critical to stop smoking as soon as possible.
“For former smokers, it is important to remain ‘former,’ and the longer one is away from smoking, the better the outcome of lung cancer treatment should you develop the disease,” Dr. Christiani says.
How Many People Have Lung Cancer?
Lung cancer stands as the second and most prevalent cancer among both men and women, according to the American Cancer Society. In 2023, it is estimated that nearly 240,000 new cases of lunch cancer will arise in the United States, resulting in approximately 125,000 deaths. The majority of these cases, approximately 80 to 85 percent fall under the category of non-small-cell lung cancer (NSCLC).
To better understand the beneficial impact of quitting smoking before an NSCLC diagnosis, researchers looked at data from over 5,594 individuals enrolled in the Boston Long Cancer Survival Cohort at Massachusetts General Hospital from 1992 to 2022. The participants included 795 individuals who had never smoked, 3,308 former smokers, and 1,491 current smokers.
These individuals completed questionnaires regarding their smoking habits and provided other health and demographic information at the outset. Researchers then tracked their survival every 12 to 18 months.
Prolonged Survival Has Significant Association with Doubled Years of Quitting Smoking
What made this study unique was its examination of mortality not only among current and never-smokers but also among former smokers. The study’s robust findings were strengthened by the diverse range of participants, some of whom had quit smoking only a few years before their diagnosis, while others had ceased smoking several decades earlier.
During the course of the study, 3,842 participants passed away, with 79.3 percent of current smokers, 66.8 percent of former smokers, and 59.6 percent of never-smokers succumbing to their conditions.
Here are some of the key findings from the study:
- Never smoking was associated with the highest odds of survival following a lung cancer diagnosis, but the study revealed significant correlations between lower mortality rates and quitting smoking before the diagnosis.
- The longer a patient had refrained from smoking, the more pronounced the health benefits. Among former smokers, doubling the years of smoking cessation before their lung cancer diagnosis was linked to significantly prolonged survival.
- Conversely, doubling of smoking pack years was linked to shorter survival rates among both current and former smokers.
Dr. Christiani says, “These results are consistent with the 2020 Surgeon General’s Report (SGR) demonstrating that quitting smoking even after a cancer diagnosis is associated with improved cancer treatment outcomes.”
He also explained that these recent discoveries indicate that the advantages of quitting smoking before a lung cancer diagnosis continue to be effective, even after the diagnosis, leading to improved responses to treatments like surgery, radiation, and chemotherapy.
“For those with curative treatment, the chances of remaining disease-free are much better, and, in more advanced disease, the chances of longer survival are better,” says Dr. Christiani.
Peter Shields, MD, a medical oncologist and the Julius F. Stone Chair in Cancer Research at the Ohio State University Comprehensive Cancer Center in Columbus, praised the study, emphasizing that it confirms the critical importance of quitting smoking before a lung cancer diagnosis. Dr. Shields, who was not involved in the research, pointed out that cessation at any age is valuable.
Will Quitting at Time of Lung Cancer Diagnosis Help Prolong Survival?
Dr. Shields explains, “The question that this study doesn’t address is the million-dollar question: Does quitting smoking at the time of lung cancer diagnosis improve your outcome and help you live longer? We have these patients who come in with lung cancer, and we tell them to stop smoking because we know that it reduces toxicity. But it would be nice if we actually knew that it also helped them live longer.”
He adds that while there’s a critical gap in the research, if the researchers manage to continue following the participants, they could have very helpful data in the future.
Quitting At Any Age Is a Good Idea
Choosing to quit smoking is always a good idea, and this study managed to reinforce this message. According to Dr. Shields, even before you’re diagnosed with lunch cancer, regardless of how old you may be, quitting smoking is beneficial because it’ll give you a better chance of survival.
“What’s a shame is that people who quit smoking still get lung cancer. There are some people who wrongly think that if you quit smoking for 10 or more years, that your risk goes down to the lung cancer risk for never-smokers. That’s not true,” he says.
He also highlighted that quitting smoking reduces the risk of lung cancer by 30 to 50 percent after 10 years compared to continued smoking. Additionally, quitting smoking cuts the risk of mouth or esophageal cancer in half within 5 years of quitting, says the National Cancer Institute.
However, Dr. Shields noted that it would have been interesting if the study had included data categorized by the type of lung cancer, mutation status, and treatment, as these factors could also influence survival rates.
The researchers acknowledged that the associations between survival and smoking history may differ based on the clinical stage at which lunch cancer is diagnosed, and the study did not account for the diverse treatments received by participants.
Are You Ready to Quit Smoking?
If you’re a smoker but you’re ready to quit, the Centers for Disease Control and Prevention (CDC) websiteprovides a number of resources to get you started.
In addition to counseling and support groups, there are a number of medications your doctor can prescribe that can help you double your chances of successfully quitting smoking, says the CDC.
Recommended For You
