Biomarkers, Tumor/analysis; Carcinoma, Squamous Cell/enzymology; Head and Neck Neoplasms/enzymology; Isoenzymes/analysis; Matrix Metalloproteinase 9/analysis; Neoplasm Proteins/analysis; Neovascularization, Pathologic/enzymology; Adult; Aged; Aged, 80 and over; Biomarkers, Tumor/biosynthesis; Biomarkers, Tumor/genetics; Carcinoma, Squamous Cell/blood supply; Carcinoma, Squamous Cell/mortality; Carcinoma, Squamous Cell/pathology; Disease Progression; Endothelial Growth Factors/analysis; Endothelial Growth Factors/biosynthesis; Endothelial Growth Factors/genetics; Enzyme Induction; Female; Fibroblast Growth Factor 2/analysis; Fibroblast Growth Factor 2/biosynthesis; Fibroblast Growth Factor 2/genetics; Gene Expression Regulation, Neoplastic; Head and Neck Neoplasms/blood supply; Head and Neck Neoplasms/mortality; Head and Neck Neoplasms/pathology; Humans; Isoenzymes/biosynthesis; Isoenzymes/genetics; Life Tables; Lymphokines/analysis; Lymphokines/biosynthesis; Lymphokines/genetics; Male; Matrix Metalloproteinase 9/biosynthesis; Matrix Metalloproteinase 9/genetics; Middle Aged; Neoplasm Invasiveness; Neoplasm Proteins/biosynthesis; Neoplasm Proteins/genetics; Neovascularization, Pathologic/genetics; Prognosis; Survival Analysis; Vascular Endothelial Growth Factor A; Vascular Endothelial Growth Factors