GPR18 and head and neck squamous cell carcinoma: In this work, we present for the first time FABP4, GDNF, HMGA2, S100A10, SLC7A2, and GPR18 as potential prognostic biomarkers exclusively for HPV-positive HNSCC and ST6GALNAC1 only for HPV-negative HNSCC, which despite showing a significant prognostic value, need to be evaluated in different cohorts with characteristics inherent to the study population, in addition to the inclusion of other molecular techniques such as immunohistochemistry or PCR, which have shown great clinical utility.