CDR2 and neoplasm: More recent studies of ovarian tumors from patients with paraneoplastic cerebellar degeneration and anti-Yo antibodies, the major antibodies associated with the condition, have demonstrated that, although ovarian tumors from anti-Yo–positive and anti-Yo–negative patients were histologically similar, ovarian tumors from anti-Yo–positive patients differ from tumors from patients without anti-Yo antibodies by high rates of genetic alterations in key CDR and, to a greater extent, CDR2L (CDR2-like) Yo antigens and by intense tumor infiltration by plasma cells and cytotoxic CD8+ lymphocytes11,12.