Hypoalbuminemia and hypercalcemia are independently associated with poor treatment outcomes of anti-PD-1 immune checkpoint inhibitors in patients with recurrent or metastatic head and neck squamous cell carcinoma

Abstract Background Recent randomized phase III trials have demonstrated the efficacy of anti-programmed cell death 1 (PD-1) immune checkpoint inhibitors (ICIs) in treating patients with recurrent or metastatic head and neck squamous cell carcinoma (RMHNSCC). However, a large proportion of such patients still have poor response. This study aimed to identify biomarkers for predicting anti-PD-1 ICI treatment outcomes . Methods We retrospectively analyzed 144 patients with RMHNSCC who received anti-PD-1 ICIs after progression to platinum-based chemotherapy between January 2017 and December 2022 at Kaohsiung Chang Gung Memorial Hospital. Data on clinicopathological parameters, albumin levels, calcium levels, and other pretreatment peripheral blood biomarkers, including total lymphocyte count, neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), lymphocyte-to-monocyte ratio (LMR), and prognostic nutritional index (PNI) were collected and correlated with the treatment outcome of anti-PD-1 ICIs. Results Low tumor proportion score (TPS), low combined positive score (CPS), NLR ≥ 5, PLR ≥ 300, hypercalcemia, hypoalbuminemia, and PNI