Anti-Yo positive paraneoplastic cerebellar degeneration: a report of three cases and review of the literature.

Anti-Yo is an anti-Purkiney cell cytoplasmic antibody found in approximately 50% of patients with parancoplastic cerebellar degeneration (PCD). We report three patients with anti-Yo positive PCD (one ovarian carcinoma and two poorly differentiated adenocarcinomas consistent with breast origin). Two were treated with chemotherapy and plasmapheresis but died within months of the diagnosis from progressive neurological disease. The other was given gamma-globulin and has remained table at 6 months follow up. Anti-Yo antibodies are highly specific with almost all patients having breast or gynaecological malignanies. Commonly the tumour is of small volume and asymptomatic. Attempts at treatment are usually unsuccessful but there are a number of reports of stabilisation or improvement when treatment is begun before the development of severe neurological disability. The detection of anti-Yo antibodies is very useful for the diagnosis of PCD allowing early tumour detection and prompt institution of treatment.