Persistent Ethnicity-Associated Disparity in Antitumor Effectiveness of Immune Checkpoint Inhibitors Despite Equal Access

Abstract

We reviewed response to immune checkpoint inhibitors (ICI) of 207 patients with diagnoses of lung or head and neck cancer treated with chemotherapy/ICI combination therapy and ICI monotherapy between 2015 and 2020 at one of three clinical pavilions associated with the Dan L. Duncan Comprehensive Cancer Center at Baylor College of Medicine. Two of these pavilions (Harris Health System and the Michael E. DeBakey Veterans Affairs Medical Center) serve large minority populations and provide equal access to care regardless of means. 174 patients had a diagnosis of lung cancer (non-small cell or small cell) and 33 had a diagnosis of head and neck squamous cell carcinoma (HNSCC). 38% self-identified as Black, 45% as non-Hispanic White, and 18% as Hispanic. The objective response rate (ORR) was similar for lung cancer (35.057%) and HNSCC patients (30.3%) (p=0.894). The ORR for Hispanic and Black patients was lower compared to non-Hispanic White patients (H 27.0%, B 32.5%, W 38.7%; H vs. W p=0.209; B vs. W p=0.398). When considering only patients treated with ICI monotherapy, the ORR for Hispanic patients dropped further to 20.7% while the ORR of Black and non-Hispanic White patients remained about the same (B 29.3% and W 35.9%, H vs. W p=0.133; B vs. W p=0.419). Immune related adverse events were the lowest in the Hispanic population occurring in only 30% of patients compared to 40% of patients in the Black cohort and 50% of the non-Hispanic White cohorts.

Real-World Survival of First-Line Immune Checkpoint Inhibitor Treatment Versus Chemotherapy in Older Patients With Non–Small-Cell Lung Cancer and Synchronous Brain Metastases

“…A review study reporting ORRs of ICIs in patients with lung cancer stratifying by race and ethnicity reported comparable antitumor effects of ICIs regardless of race/ethnicity; however, the study included patients with NSCLC and small-cell lung cancer and did not separately report findings for NSCLC. 56 Our study provides novel insights because, to our knowledge, no studies have reported sex or race differences in immunotherapy efficacy in patients with NSCLC and BM. However, neither previous studies nor our study are designed to test immunotherapy efficacy by sex or race/ethnicity.…”

Complete Metabolic Response to Combined Immune Checkpoint Inhibition after Progression of Metastatic Colorectal Cancer on Pembrolizumab: A Case Report

“…Possibly, the patient's good performance status at most points of the therapy, limited pre-existing illnesses (ischemic stroke without remains, hyperlipidemia), and the limited co-medication (ASS, rosuvastation, ezetimib) have contributed to an undelayed therapy administration and might have, thus, also contributed to this excellent therapeutic response. Moreover, the ethnicity of our patient might have influenced the response to ICI therapy, as non-Hispanic white patients are known to show higher response rates [50,51]. Hence, demographics and treatment characteristics might have impacted the therapy response.…”

Challenges and Future Directions in the Management of Tumor Mutational Burden-High (TMB-H) Advanced Solid Malignancies

“…Thus, a more accurate classification of tumor-only TMB estimation may be achieved by taking into account the genetic ancestry data, especially given the evidence of variation in the germline mutational burden across diverse racial groups [161,162]. It is possible that intracellular factors exhibit variations influencing the response to ICIs across diverse racial groups [163,164]. There is a need for the development of race/ethnicity-based algorithms for tissue-agnostic TMB estimation.…”