Lung Cancer Treatment: Weight Affects Post-surgery Outcomes; Obese Patients Less Likely to die

A new study from the researchers at University of Chicago reveals that lung cancer surgery patients have a higher risk of complications and death if they are underweight or overweight, Healthday reports. For the study, researchers analyzed more than 41,000 lung cancer surgery patients between 2009 and 2014 and categorized them according to their body mass index (BMI).

Researchers noted that this study could not prove cause and effect, but showed, however, that patients who were underweight or severely obese were at highest risk of complications and death after their surgery. Another interesting discovery, however, is that overweight and slightly obese patients had a decreased risk for complications compared to their normal weight counterparts.

According to study co-lead author Dr. Mark Ferguson of the University of Chicago, patients who are overweight or are slightly obese need not be afraid of undergoing lung surgery, because based on this study, they are the group that has the best outcomes following lung surgery. However, he still recommends exercise for proper health maintenance.

"[Weight] is associated with a patient's overall physiology and health, but overweight people need to have more muscle to carry the extra weight around," study co-leader Dr. Trevor Williams of the University of Chicago said in a society news release, as per WebMD. Underweight individuals would also be frail, "which is associated with impaired strength, reduced activity and being easily fatigued. There also may be an association with immune system impairment. All of these factors adversely affect outcomes after lung surgery."

"Both very thin and [very] obese patients have higher rates of complications following removal of part of the lung. [Obese patients] had the highest risk for complications, likely a result of associated conditions like diabetes, hypertension [high blood pressure] and heart disease," Dr. Len Horovitz, a pulmonary specialist at Lenox Hill Hospital in New York City, commented.

In 2015, there were an estimated 221,200 new cases of lung cancer in the United States alone, and 158,040 deaths were linked to the disease, the American Cancer Society reports. According to the CDC, African-Americans were more likely to die from lung cancer than any other race or ethnicity. Additionally, lung cancer often occurs in older people and two out of three individuals found to have lung cancer are 65 years old or older.

According to Cancer Research UK, lung cancer treatment highly depends on the type of cancer an individual has. Small cell lung cancer, which accounts for 10% to 15% of all lung cancers, beings in the bronchi and spreads widely through the body in the early stages of the disease. Nonsmall-cell lung cancer, which accounts for 85% to 90% of all lung cancers, on the other hand, is subdivided into three more categories based on the size, shape, and chemical composition of the cell.

Because of these differences, treatment also differs. Small cell lung cancer is often treated with chemotherapy, while nonsmall-cell lung cancer is treated with surgery, chemotherapy, radiotherapy, or a combination of such treatments.