Background: EGFR mutations are overrepresented in non-small cell cancer (NSCLC) patients from Asian descent and in female NSCLC patients. This, in combination with the general underutilization of NSCLC tumor genetic testing and targeted therapy will likely lead to undertreatment in sex and racial/ethnic minority patients.
Objectives: Using an electronic medical records (EMR) database for healthcare organizations worldwide, we aimed to investigate the proportion of US lung cancer patients per sex and racial/ethnic minority group treated with EGFR inhibitors.
Methods: NSCLC patients using EGFR inhibitors (afatinib, dacomitinib, erlotinib, gefitinib or osimertinib) were identified using RxNorm and ICD-10-CM codes. Proportions of sex and racial minority group patients were determined among all patients with lung cancer and those using EGFR inhibitors.
Results: In total, 11,025 of the 468,079 identified patients with malignant lung cancer were treated with ≥1 EGFR inhibitor (24%). Patients were most frequently treated with erlotinib (n=6,596), followed by osimertinib (n=4,875), afatinib (n=1,373), gefitinib (n=586) and dacomitinib (n=34). Across the top 3 used EGFR inhibitors (erlotinib, osimertinib and afatinib), 60-68% were female, 32-40% were male, 64-69% were White, 9-12% were Black or African American, 7-15% were Asian (with 10-17% of unknown race) and 3-5% were Hispanic (13-24% of unknown ethnicity). EGFR inhibitor users compared to all malignant lung cancer patients were more often female (60-68% [in line with earlier studies] vs 49%) and more often from Asian descent (7-15% vs 2%). The number of NSCLC patients from Asian descent on EGFR inhibitors is lower than expected given the high prevalence of EGFR mutations in this patient subgroup (30-70%). For other racial and ethnic groups, no differences were seen between EGFR inhibitor users and the overall group of malignant lung cancer patients, respectively, 63% vs 70% were White (US population ~72%), 11% vs 12% were Black/African American (US population ~13%) and 4% vs 3% were Hispanic (lower than the US population percentage of ~20%).
Conclusions: Identifying undertreatment in minority groups is crucial for improving access to drugs. However, undertreatment of certain minority groups will have consequences for establishing the risk and benefits of drugs in these groups from secondary data sources. Besides fewer patients being available for research, there will be an increased need for balancing baseline characteristics when comparing different minority groups due to an increased potential for selection bias. Future analyses will focus on treatment sequencing and specific EGFR mutations (exon 19 deletions or the missense mutation L858R).
