RESUMEN
BACKGROUND: Immune checkpoint inhibitors (ICI) have profoundly impacted survival among patients with metastatic non-small cell lung cancer (NSCLC). However, population-based studies evaluating this impact on survival by race and socioeconomic factors are lacking. METHODS: We utilized the SEER-Medicare database to identify patients with metastatic NSCLC diagnosed between 2015 and 2019. The primary study outcomes were the receipt of an ICI and overall survival (OS). Chi-square tests and logistic regression were utilized to identify demographic factors associated with receipt of ICI. The Kaplan-Meier method was used to calculate 2-year OS rates, and log-rank tests were used to compared survival by race/ethnicity. RESULTS: Out of 17,134 patients, approximately 39% received an ICI. Those diagnosed with cancer recently (in 2019), who are relatively younger (<85 years old), non-Hispanic white, non-Hispanic Asian, or Hispanic, living in high socioeconomic status or metropolitan areas, not Medicaid eligible, and with adenocarcinoma histology were more likely to receive ICI. The 2-year OS rate from diagnosis was 21% for the overall population. The 2-year OS rate from ICI initiation was 30%, among those who received at least one cycle and 11% among those who did not receive ICI. The 2-year OS rates were higher among non-Hispanic whites (22%) and non-Hispanic Asians (23%) compared to non-Hispanic Blacks (15%) and Hispanics (17%). There was no significant racial differences in survival for those who received ICI. CONCLUSION: ICI utilization rates and the resulting outcomes were inferior for certain vulnerable groups, mandating the need for strategies to improve access to care.
RESUMEN
BACKGROUND: African Americans have higher incidence and mortality from lung cancer than non-Hispanic Whites, but investigations into differences in immune response have been minimal. Therefore, we compared components of the tumor microenvironment among African Americans and non-Hispanic Whites diagnosed with non-small cell lung cancer (NSCLC) based on PD-L1 or tertiary lymphoid structure (TLS) status to identify differences of translational relevance. METHODS: Using a cohort of 280 NSCLC patients from the INHALE study (non-Hispanic White: n=155; African American: n=125), we evaluated PD-L1 tumor proportion score (<1% vs. ≥1%) and TLS status (presence/absence), comparing differences within the tumor microenvironment based on immune cell distribution and differential expression of genes. RESULTS: Tumors from African Americans had a higher proportion of plasma cell signatures within the tumor microenvironment than non-Hispanic Whites. In addition, gene expression patterns in African American PD-L1 positive samples suggest these tumors contained greater numbers of γδ T-cells and resting dendritic cells, along with fewer CD8+ T-cells after adjusting for age, sex, pack-years, stage, and histology. Investigation of differential expression of B-cell/plasma cell related genes between the two patient populations revealed that two immunoglobulin genes (IGKV2-29 and IGLL5) were associated with decreased mortality risk in African Americans. CONCLUSIONS: In the first known race-stratified analysis of tumor microenvironment components in lung cancer based on PD-L1 expression or TLS status, differences within the immune cell composition and transcriptomic signature were identified that may have therapeutic implications. IMPACT: Future investigation of racial variation within the tumor microenvironment may help direct the use of immunotherapy.
RESUMEN
PURPOSE: Non-small-cell lung cancer (NSCLC) with STK11mut has inferior outcomes to immune checkpoint inhibitors (ICIs). Using multiomics, we evaluated whether a subtype of STK11mut NSCLC with a uniquely inflamed tumor immune microenvironment (TIME) harboring TP53 comutations could have favorable outcomes to ICIs. PATIENTS AND METHODS: NSCLC tumors (N = 16,896) were analyzed by next-generation sequencing (DNA-Seq/592 genes). A subset (n = 5,034) underwent gene expression profiling (RNA-Seq/whole transcriptome). Exome-level neoantigen load for STK11mut NSCLC was obtained from published pan-immune analysis. Tumor immune cell content was obtained from transcriptome profiles using the microenvironment cell population (MCP) counter. ICI data from POPLAR/OAK (n = 34) and the study by Rizvi et al (n = 49) were used to model progression-free survival (PFS), and a separate ICI-treated cohort (n = 53) from Dana-Farber Cancer Institute (DFCI) was used to assess time to treatment failure (TTF) and tumor RECIST response for STK11mutTP53mut versus STK11mutTP53wt NSCLC. RESULTS: Overall, 12.6% of NSCLC tumors had a STK11mut with the proportions of tumor mutational burden (TMB)-high (≥10 mut/Mb), PD-L1 ≥50%, and microsatellite instability-high being 38.3%, 11.8%, and 0.72%, respectively. Unsupervised hierarchical clustering of STK11mut (n = 463) for stimulator of interferon-gamma (STING) pathway genes identified a STING-high cluster, which was significantly enriched in TP53mut NSCLC (P < .01). Compared with STK11mutTP53wt, tumors with STK11mutTP53mut had higher CD8+T cells and natural killer cells (P < .01), higher TMB (P < .001) and neoantigen load (P < .001), and increased expression of MYC and HIF-1A (P < .01), along with higher expression (P < .01) of glycolysis/glutamine metabolism genes. Meta-analysis of data from OAK/POPLAR and the study by Rizvi et al showed a trend toward improved PFS in patients with STK11mutTP53mut. In the DFCI cohort, compared with the STK11mut TP53wt cohort, the STK11mutTP53mut tumors had higher objective response rates (42.9% v 16.7%; P = .04) and also had longer TTF (14.5 v 4.5 months, P adj = .054) with ICI. CONCLUSION: STK11mut NSCLC with TP53 comutation is a distinct subgroup with an immunologically active TIME and metabolic reprogramming. These properties should be exploited to guide patient selection for novel ICI-based combination approaches.