There are nearly 30 different antibodies associated with PCD [84]; these include anti-Yo (PCA-1), anti-Hu, anti-Ri, anti-Tr, anti-VGCC, anti-Ma, anti-CRMP5 (anti-CV2), and anti-mGluR [27] These antibodies are found in 80% of PCDs [15] and each one of them correlates with specific tumour types [16], thus guiding the search for the causative cancer. This evidence concerns the gene CDR2 and cancer.