CEACAM5 and squamous cell carcinoma: Compared to traditional tumor markers, such as CEA (Carcino Embryonic Antigen), SCC (Squamous Cell Carcinoma Antigen), TPS (Tissue Polypeptide Specific Antigen), and CYFRA 21-1 34, 35, FOXD1 had a greater ability to discriminate patients with HNSCC from healthy individuals, which indicated that FOXD1 could serve as a potential early diagnostic biomarker for HNSCC, especially when combined with other efficient markers.