Improved Survival for Patients Diagnosed With Lung Cancer Who Have Never Smoked
The results of a recent study published in the journal Chest indicate that patients who have never smoked and have been diagnosed with adenocarcinoma have improved survival compared to patients who are current smokers.
Lung cancer is the leading cause of cancer-related deaths in the United States and Europe. Non-small cell lung cancer is a malignancy that arises from the cells within the lung. Adenocarcinoma is one of 5 types of non-small cell lung cancer. Other types of non-small cell lung cancer include squamous cell, adenosquamous carcinoma, large cell carcinoma, and undifferentiated carcinoma. Each type of non-small cell lung cancer is defined by the physical characteristics of the cells and how they appear under the microscope. Smoking can be attributed to 85% of diagnosed cases of lung cancer due to the damage of lungs caused by cigarettes. Factors determining a smokerâ€™s risk include the number of years the person has been smoking, as well as the number of cigarettes smoked each day.
In this recent study, data were gathered at the H. Lee Moffit Cancer Center regarding 132 never smokers and 522 current smokers, all diagnosed with adenocarcinoma of the lung. Former smokers were not included in the study. Detailed demographic information was compiled for survival information. When compared, the age at diagnosis was higher for patients who had never smoked compared to the current smokers. In addition, there was an increased percentage of women among those who had never smoked (78% vs. 54%). Finally, 5-year survival was 23% for the patients who had never smoked compared to 16% for current smokers.
Researchers concluded that patients who had never smoked and were diagnosed with adenocarcinoma were largely female, were diagnosed at a higher age and had improved survival when compared to current smokers. The survival benefit may be partly attributed to the health status of the non-smoker, who is less likely to have other chronic conditions often associated with smoking, such as heart disease or chronic obstructive pulmonary diseases. Future studies of non-smokers will be necessary in order to learn more about the differences in non-smokers diagnosed with lung cancer and such studies may be useful for determining the characteristics of cancer in this specific population.
Reference: Nordquist L, Simon G, Cantor A, et al. Improved survival in never-smokers vs. current smokers with primary adenocarcinoma of the lung. Chest. 2004; 126: 347-351.