Abstract: Single reagent chromometric analysis for the measurement of serum sialic acid (SSA) levels has been used.This test has been applied to human sera of which came from normal in dividuals and patients with lung cancer, pneumonia and pulmonary tuberculosis.Track observing result of the level from 41 patients with lung cancer before and after treatment is especially interesting.It' s demonstrated that: ① SSA concentrations were found to be very significantly increased (P<0.01) in the group of lung cancer patients as compared to those of normal groups.There is a significant difference between SSA levels in the group with lung cancer and both those with pneumonia and pulmonary tuberculosis also (P<0.05).②SSA levels were found to be increased in both groups of pneumonia and pulmonary tuberculosis patients comparing with those of normal groups (P<0.05),but it' s not so obviously as those with lung cancer.③ With the remission by the surgery and chemotherapy,SSA levels were found to be reduced obviously(P<0.01) in 30 patients with lung cancer as compared to those before treatment.The other 11 patients were determination after treatment.Their SSA concentrations became higher obviously than those before treatment (P<0.01).Here we show that determination of SSA has important value for diagnosis of lung cancer.

Key words: serum sialic acid (SSA), lung cancer, pulmonary tuberculosis, pneumonia