Abstract: Objective To evaluate the value of anti-oncogene hypermethylation in bronchial lavages fluid （BLAF） for the diagnosis of primary lung cancer. MethodsSeventy-eight patients with lung tumors (containing 51 patients with lung cancer and 27 patients with benign pulmonary lesions) from Beijing Tuberculosis and Thoracic Tumor Research Institute were selected. DNAs from supernate and cell in bronchial lavages were extracted, quantified, and detected promoter hypermethylation of three target genes, including p16, MGMT and RASSF1A. Using final clinical diagnosis as control, the sensitivity and specificity of promoter hypermethylation in the diagnosis of lung cancer were analyzed. ResultsDNA concentrations from supernate of bronchial lavages had not significant difference among central lung cancer, peripheral lung cancer and pulmonary benign lesions group. The sensitivity and specificity of anti-oncogene hypermethylation from the bronchial lavages cells for the diagnosis of central lung cancer were 85.2% and 81.5% respectively; for peripheral lung cancer were 54.2% and 81.5%, respectively. Combining with the detection of bronchial lavages supernates, the sensitivity and specificity for the diagnosis of central lung cancer were 88.9% and 70.4% respectively, for peripheral lung cancer were 75.0% and 70.4% respectively.ConclusionsHypermethylation of anti-oncogene might be an useful marker for the diagnosis of lung cancer.

Key words: lung neoplasms, Bronchoalveolar lavage fluid, O(6)-Methylguanine-DNA methyltransferase, tumor suppressor proterins, methylation