The panel also acknowledges that the present criteria do not identify as definite PNS neurologic syndromes associated with cancer and low-risk antibodies even if tumor cells express the neuronal antigen recognized by the antibody (e.g, neuromyelitis optica with aquaporin 4 antibodies and concurrent lung adenocarcinoma that expresses aquaporin 4). This evidence concerns the gene AQP4 and neuromyelitis optica.