Aggregating Hispanic patients with cutaneous T-cell lymphoma obscures survival differences compared to non-Hispanic white patients

Summary: Comparisons of survival outcomes between Hispanic patients with cutaneous T-cell lymphoma (CTCL) and Non-Hispanic White (NHW) patients have yielded conflicting results. However, prior studies have classified all Hispanic populations as one group, despite considerable heterogeneity in national origin. To disaggregate Hispanic patients, we queried the National Cancer Database (NCDB) for patients diagnosed with CTCL from 2004-2020. Overall survival (OS) was compared using the log-rank test, and hazard ratios (HRs) were calculated using a multivariable Cox proportional hazard model. Missing data were handled with multiple imputation by chained equations. Out of 15,276 patients with CTCL, we identified 14,264 NHW and 1,012 Hispanic patients, of whom 111 were Mexican, 87 were South/Central American, 115 were Caribbean, and 699 were Other Hispanic. Compared to NHW patients, aggregated Hispanic patients had higher rates of OS (log-rank test, p < .001). In a multivariable Cox model, there were no differences in OS among aggregated Hispanic patients and NHW patients (HR 0.93; 95% CI, 0.80-1.10), but after disaggregation, Caribbean patients had significantly greater OS than NHW (HR 0.64; 95% CI, 0.41-0.99). There were no significant differences between other Hispanic populations and NHW patients. We demonstrate that Caribbean patients with CTCL in the NCDB may have significantly improved OS compared to NHW patients, even after adjusting for covariates. Our findings challenge the assumption that Hispanic populations with CTCL can be aggregated in clinical research. More studies are needed to investigate other potential contributors to survival differences not captured in NCDB, such as genetic ancestry, the immigrant health effect, and environmental mediators. Bryan L. Peacker^{1, 2}, Natalie Baker^{1, 2}, Natalie Braun^{1, 2}, Ghida El-Banna², Kevin Ma², Steven Chen^{1, 2} 1. Harvard Medical School, Boston, MA, United States. 2. Massachusetts General Hospital, Boston, MA, United States. Minoritized Populations and Health Disparities Research