ABSTRACT
The HER-2/neu gene is located on chromosome 17q21 and encodes a 185-kDa transmembrane glycoprotein with tyrosine kinase activity reported to be released in soluble form in various malignancies. To evaluate the clinical significance of soluble Her-2/neu as a diagnostic marker in lung cancer. Serum levels of soluble HER-2/neu were measured in 43 patients with lung cancer and 42 age and sex matched controls by an enzyme immunoassay method. Mean serum level of soluble Her-2/neu in cancer patients was 6.07 +/- 10.37 ng/ml which was significantly higher than the control group [P < 0.05]. Cigarette smoking had no effect on the level of soluble HER-2/neu. A cut off value of 6.1ng/ml revealed a high specificity [95%] for diagnosis of lung cancer, but a very low sensitivity [14%]. The results of this study show an increased level of soluble HER-2/neu in the sera of lung cancer patients with a high specificity but low sensitivity for diagnosis of lung cancers