GAD2 and breast cancer: GAD65 is rarely associated with paraneoplastic TM.[12,13] It is more frequently found in patients with non-neurological autoimmune diseases.[12] Neurological autoimmune conditions linked to GAD65 include conditions such as stiff person syndrome and limbic encephalitis.[12] The few malignancies associated with GAD65 have been lung/breast cancers and thymomas.[13]