A real-world study on biomarker retesting among patients with non-small cell lung cancer and disparity in outcomes

Prior studies revealed sociodemographic disparities in biomarker testing among patients (pts) with advanced/metastatic non-small cell lung cancer (a/mNSCLC). However, the association of testing disparities with clinical outcomes among real-world pts requires further characterization.

This retrospective study used ConcertAI Patient360™ US dataset to assess biomarker testing disparities and their association with median overall survival (mOS) among adults with a/mNSCLC (2017–2022) who received ≥1 line of therapy with ≥90-day follow-up. Analyses were conducted in pts who initiated first-line (1L) treatment and stratified by setting (community vs academic) and race. Biomarker testing is a curated data element in this database, leveraging structured and unstructured electronic medical record data and includes the following biomarkers ALK, BRAF, EGFR, KRAS, MET amp, MET exon 14, NTRK, PD-L1, RET, and ROS1. Biomarker testing to inform 1L decision was defined as testing before 1L start. Testing to inform second-line (2L) decision was defined as testing after 1L start and before 2L start. Variables were compared using chi-square or ANOVA tests. Unadjusted and adjusted OS using multivariate Cox proportional hazards are reported.

Of 3678 pts included in the 1L cohort, 3127 (85%) received 1L testing. In community settings, 22% of Black pts vs 15% of White pts did not receive 1L testing (P=0.002), whereas 1L testing rates between races were similar in academic settings (Table). In 2L community setting among pts who received 1L but not 2L testing, mOS was 5.9 vs 9.9 months in Black (n=54) vs White (n=529) pts, respectively (P=0.35). In 2L community setting among pts who were and were not tested prior to 1L and not tested at 2L, mOS was 5.9 vs 10.1 months in Black (n=62) vs White (n=613) pts, respectively (P=0.27). Accounting for recorded sociodemographic and clinical characteristics at baseline, differences in OS by testing setting and status start to normalize to the reference group. Disparities within groups appear to potentially exist despite no statistical significance (except for ECOG score of 2+).

Despite small 2L sample sizes and lack of significance, disparities in testing rates and outcomes were observed, which may be overcome by normalizing testing across race and treatment setting to potentially improve pt outcomes. Further analysis can be performed across census regions. Further research is needed to confirm the impact of lack of biomarker testing on pt outcomes on a broader scale, particularly around characteristics that may impact outcomes but were undetected in this dataset.