“…Early studies reported very low sensitivity of various markers like CEA (carcinoembryonic antigen) (Silverman et al, 1976;Walther et al, 1990), Lipid associated sialic acid (Katopodis et al, 1982;Ropka et al, 1991) and SCC-marker (TA-4) (Calsen et al, 1990;Daver et al, 1990;Fichbach et al, 1990;Walther et al, 1990;Yoshimura et al, 1990;Ropka et al, 1991) in head and neck cancer patients. Cyfra 21-1 was reported as a new marker for non-small cell carcinoma of the lung (Pujol et al, 1993;Stieber et al, 1993;Rastel et al, 1994).…”