These disorders are usually paraneoplastic mainly in adult patients, and a range of tumors have been found to be associated, as small cell lung cancer (anti-Hu, CRMP5, and amphiphysin), breast cancer (CRMP5, anti-Yo, and amphiphysin), testicular teratoma (MA2), Hodgkin lymphoma (Tr antibodies), and thymoma (CRMP5). This evidence concerns the gene AMPH and breast cancer.