The Association between Serum Cancer Antigen 125 (CA 125) and Risk of Lung Cancer in Females: Assessing the Possibilities for Early Detection

Abstract

Background: Few studies have closely examined the relationship between CA 125 and lung cancer. This study is expected to provide more understanding about CA 125 and its role as a potential predictor for lung cancer risk. Objectives: To evaluate: i) the association between CA 125 and lung cancer; ii) if the associations differ by potential effect modifier (smoking status); and iii) if the association between CA 125 and lung cancer differs by lung cancer stage (early vs. advanced). Methods: The present research was conducted using secondary data from the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial (PLCO) randomized controlled trial (RCT). The associations between explanatory variables and lung cancer were evaluated using multivariable logistic regression. Each multivariable logistic regression model was adjusted for age, education, current body mass index (BMI), family history of lung cancer, personal history of cancer, chronic obstructive pulmonary disease (COPD), average number of cigarettes smoked per day and number of years smoked. Results: The study demonstrated that CA 125 is significantly and independently associated with lung cancer and that CA 125 is associated with early-stage lung cancer. It was found that an elevated CA 125 level was associated with a higher risk of lung cancer in individuals who smoked. Although the study demonstrated promising results, CA 125 did not have a large effect on the study’s lung cancer risk prediction models. Conclusion: CA 125 is not a strong enough predictor to be used as an indicator in lung cancer screening alone, however it may be useful in a panel of complimentary biomarkers. Future research is needed to explore whether a panel of complimentary biomarkers including CA 125 can improve lung cancer risk prediction.