High ALK autoantibody levels (defined in this study as an O.D. value greater than three standard deviations above the mean among ALK negative NSCLC cases, i.e. > O.D. 871.5) were detected in 9 of 53 (17.0%) ALK-positive NSCLC cases and 0 of 38 (0%) ALK-negative NSCLC cases (P < 0.01). The gene discussed is ALK; the disease is non-small cell lung carcinoma.