Women are Underrepresented in Non-small Cell Lung Cancer Clinical Trials: A Systematic Review

Purpose. To perform a systematic review of clinical trials examining non-small cell lung cancer (NSCLC) to better understand the equity afforded to women in the study of lung cancer. Methods. An electronic search was conducted for all NSCLC clinical trials published between 2010 and 2020 with included words "carcinoma, non-small cell, lung" and "non-small cell lung cancer." Studies from PubMed, Cochrane, and SCOPUS were included and were uploaded into Covidence to assist with systematic review. All articles were screened by two separate individuals and reviewed for location, study type, cancer stage, field of study of the research team, and percentage of females included. Student's t-test was used to compare the means of males and females. Results. Across the 269 studies that met inclusion criteria, fewer females than males were enrolled (38.7% vs. 61.1%; p < 0.0001). Compared with studies from 2010 to 2015, those from 2016 to 2020 had greater representation of females (36.7% vs. 41.4%, p = 0.0091, respectively). Both nonsurgical and surgical studies enrolled fewer female than male patients (38.1% vs. 61.7%, p < 0.0001; 43.1% vs. 57.2%, p = 0.0002, respectively). Clinical trials from the USA had the least difference between sexes with an average of 46.7% females enrolled. Less females compared with males were enrolled in early-stage NSCLC (37.6% female vs. 62.6% male, p < 0.0001) and late-stage NSCLC trials (37.6% female vs. 62.0% male, p < 0.0001). Conclusions. Despite recent improvement, there continues to be significant underrepresentation of females compared with males in NSCLC clinical trials.