Association of pre-treatment hemoglobin level as a prognostic factor for survival outcomes in head and neck cancer patients treated with definitive radiation.

Abstract

e18114 Background: Anemia may be associated with worse clinical outcomes in patients with head and neck squamous cell carcinoma (HNSCC), which may be related to tumor hypoxia and decreased sensitivity to radiation therapy. However, the prognostic role of baseline hemoglobin (Hgb) is not well established. To build on prior evaluations of Hgb cutoff values, we examined the association between baseline Hgb and clinical outcomes in patients with HNSCC who were treated with definitive radiation-based therapy. Methods: We conducted a retrospective analysis of patients with HNSCC who were treated with definitive radiation therapy, with or without chemotherapy, at The Ohio State University Comprehensive Cancer Center between 2011 and 2023. Baseline Hgb was categorized using a data-driven cutoff of 12.9 g/dL, and Cox proportional hazard regression was conducted to derive the effect of Hgb on overall (OS) and progression-free (PFS) survival with consideration for outcome-model covariates. Nearest-neighbor propensity score matching and subclass-stratified Cox regression were utilized to control for confounding variables. Factors contributing to low Hgb were then identified via multivariable logistic regression. Results: Stratified survival analysis found low Hgb was associated with worse OS (aHR 2.09, 95% CI 1.26–3.48; p < 0.01) and PFS (aHR 1.96, 95% CI 1.25–3.10; p < 0.01). Prognostic, multivariable covariate regression reported low baseline Hgb was associated with worse OS (aHR 1.49; p < 0.05) but not PFS (aHR 1.29 ; p = 0.12). Additional factors independently associated with worse OS and PFS included ECOG performance status ≥1 (OS aHR 1.89, p < 0.001; PFS aHR 1.63, p < 0.001) and age ≥65 (OS aHR 1.51, p < 0.05; PFS aHR 1.60, p < 0.01), while HPV-positive disease was associated with significantly improved survival outcomes (OS aHR 0.37, p < 0.001; PFS aHR 0.37, p < 0.001).. Male sex and nodal involvement was also associated with worse survival in multivariable analyses. Conclusions: In this retrospective study, a higher baseline Hgb was associated with improved overall survival in patients with HNSCC treated with definitive radiation therapy. This finding was consistent across in propensity score–matched analyses and regressions of relevant covariates. These findings support baseline Hgb as a readily available prognostic biomarker. This study provides additional data on baseline Hgb cutoffs that may help inform clinically relevant thresholds for patients with HNSCC undergoing definitive radiation-based therapy.