Lung cancer is a condition that manifests in the lung tissue, often resulting from smoking. Symptoms are infrequent in lung cancer but can include progressively worse cough, difficulty breathing, weight loss and fatigue. There are many options for treating lung cancer, and its severity or stage determines treatment options as well as outcomes after treatment. Another factor that influences long-term outcomes is whether patients continue to smoke after surgery, which can further damage the lungs following treatment.
Physicians from Washington University School of Medicine in St. Louis Department of Surgery, Siteman Cancer Center, Saint Louis University School of Medicine and VA St. Louis Health Care System collaborated on a study to understand the long-term health impact of persistent smoking after surgery for lung cancer. The study, published in the chest medicine journal CHEST, found that when patients continue to smoke following surgery for early-stage non-small cell lung cancer (NSCLC), they experienced a lower survival rate. This conclusion provides valuable information for physicians who can strongly encourage patients to stop smoking to promote better health outcomes.
Research Background and Questions
Lung cancer occurs when abnormal cells begin to grow out of control in the lung tissue. These tumors can subsequently spread to lymph nodes and other organs in the chest as they progress. There are two main types of lung cancer, the most common of which is non-small cell lung cancer (NSCLC). Early-stage NSCLC is most often treated surgically.
Many patients with NSCLC undergo surgery to remove the cancerous tissue. The surgeon removes the cancerous tumor using a procedure that best matches its size and extent. Washington University surgeons at Siteman Cancer Center are skilled at using advanced techniques to limit the amount of tissue they must remove. A sleeve resection is one novel procedure for cancers located in the main bronchus, or air tube. To perform this surgery, the cancerous portion of the bronchus is removed, and the ends are reconnected. Siteman also offers minimally-invasive and robotic procedures that reduce stress on the body and allow patients to recover faster.
Smoking is the leading cause of lung cancer, a relationship in part first discovered and described by Dr. Evarts Graham, the first full-time chairman of the department of surgery at Washington University School of Medicine. A history of smoking, even if you’ve quit, can also increase the risk of developing NSCLC. Quitting smoking is incredibly beneficial to prevent lung cancer, even if someone has smoked long-term or frequently, as the lungs can start to heal.
Smoking at the time of surgical treatment for lung cancer increases the risk of patient death after the surgery, an event known as peri-operative mortality. There is less information, however, about the health impacts of persistent smoking after the operation period.
To better understand lung cancer patient survivorship, the research-physicians asked: “What is the relationship between persistent smoking and long-term outcomes in early-stage lung cancer following surgical treatment?”
Research Methods and Results
The research was performed “retrospectively,” meaning the data on this study group had already been gathered previously. Researchers compiled a dataset from the Veterans Health Administration (VHA) of patients who had clinical stage I non-small cell lung cancer (NSCLC) and had undergone surgical treatment between 2006 and 2016. The smoking history of these patients was then assessed. Patients who were defined as “persistent smokers” were individuals who continued smoking 1 year after surgery.
7489 patients were included in the study group. About 61% of patients were smoking at the time of surgery. Of these, 58% were still smoking 1 year after surgery. In comparison, the other 39% of patients were not smoking at the time of surgery. Of these, about 20% relapsed and were smoking at 1 year after surgery. Among both groups, persistent smoking at 1 year after surgery was significantly associated with shorter overall survival. However, persistent smoking did not influence the risk of cancer recurrence.
The researchers concluded persistent smoking after surgery for stage I NSCLC is associated with lower overall survival rates, suggesting that persistent smoking following lung cancer surgery is an important factor for long-term survival. Physicians should therefore feature smoking cessation as a key element of cancer survivorship plans.
Several factors likely contribute to lower long-term survival rates in patients who persistently smoke after surgery. First author Brendan T. Heiden, MD, MPHS, reports the reasons this may be:
“First, it is likely that persistent smoking contributes to accelerated cardiovascular and other smoking-related comorbidities. Second, persistent smoking is likely associated with higher risk for other smoking-related malignancies which may contribute to shorter survival in these patients. Third, prior studies have demonstrated that the benefits of smoking cessation, especially in reducing the risk of mortality, are relatively quickly realized. We hope that patients with lung cancer are encouraged by these findings and will renew their efforts to stop smoking.”
Washington University – Working Towards the Best Outcome
Lung cancer is the leading cause of cancer death in the United States, which makes regular screenings (if you are eligible), treatment and follow-up appointments vitally important. Understanding risk factors and attending screenings increases the likelihood of catching lung cancer in its earlier and more treatable stages. This is especially important for those who engage in smoking. It is also paramount that patients with lung cancer receive the most effective treatment from leading institutions like Siteman Cancer Center, a major contributor to cancer treatment in the region.
After treatment, patients with lung cancer must receive appropriate, long-term follow-up care and direction from their medical team to increase their likelihood of a successful recovery and long, healthy life. The data of this research supports that smoking cessation is an essential element of such care plans, given the strong relationship between persistent smoking and worse survival rates. Health care providers should continue to assess smoking habits after their patients with early-stage lung cancer undergo surgery due to its impact on long-term health outcomes.
Physicians responsible for this study include:
Daniel B Eaton Jr
Mayank R Patel
Publication citation: Heiden BT, Eaton DB Jr, Chang SH, Yan Y, Schoen MW, Chen LS, Smock N, Patel MR, Kreisel D, Nava RG, Meyers BF, Kozower BD, Puri V. The impact of persistent smoking after surgery on long-term outcomes following stage I non-small cell lung cancer resection. Chest. 2021 Dec 14: S0012-3692(21)05082-0.