The significance of ferritin, lipid-associated sialic acid, CEA, squamous cell carcinoma (SCC) antigen, and CYFRA 21-1 levels in SCC of the head and neck. 
We investigated the value of some tumor markers in the diagnosis and treatment follow-up of squamous cell carcinoma of the head and neck.  Ferritin, lipid-associated sialic acid (LSA), carcinoembryonic antigen (CEA), squamous cell carcinoma (SCC) antigen and CYFRA 21-1 levels were determined in 28 patients with squamous cell carcinoma and in a control group of 20 patients with benign lesions of the head and neck.  The measurements were made before treatment and in the first and third months of treatment.  The sensitivity rates were as follows: 10.7% for ferritin, 89.3% for LSA, 21.4% for CEA, 42.9% for SCC antigen, and 14.3% for CYFRA 21-1.  The specificity was 100% for all the markers.  The sensitivity increased to 96.4% when CEA and LSA were used in combination.  Declines in the levels after treatment were significant for ferritin, CEA, SCC antigen, and LSA.  No significant relationship was found between the marker levels and lymph node metastasis, stage, and histologic differentiation of the tumors.  Only ferritin and LSA levels were correlated with tumor size.  Squamous cell carcinoma antigen was the only marker that manifested high levels in patients who developed locoregional recurrence and/or mortality.  Of the markers studied, LSA, CEA and SCC antigen may be of value in the evaluation of squamous cell carcinoma of the head and neck.  Sensitivity and specificity rates may increase when they are used in combination.