Although commercial line blot kits for antibody detection are useful for the initial screening of patients, the number of false-positive and -negative results is particularly high for line blots assessing Yo, Ma2, CV2/CRMP5, and SOX1 antibodies.e21-e25 Unexpected antibody results based on the type of neurologic phenotype, tumor, or patient's age and sex should raise concern for false-positive results and be reassessed with additional studies, preferably in research laboratories. This evidence concerns the gene PNMA2 and neoplasm.