Association of anti-Yo (type I) antibody with paraneoplastic cerebellar degeneration in the setting of transitional cell carcinoma of the bladder: Detection of Yo antigen in tumor tissue and fall in antibody titers followingtumor removal

Anti-Yo (type I) autoantibodies reactive with Purkinje cell cytoplasmic ant igens of 34 and 62 kd are found in the serum and cerebrospinal fluid of pat ients with paraneoplastic cerebellar degeneration associated with cancer of the ovary, uterus, adnexa, or breast. Anti-Yo antibody response is rarely associated with Other tumors. Here, we present a patient who developed para neoplastic cerebellar degeneration and anti-Yo antibody response in associa tion with transitional cell carcinoma of the bladder. The presence of anti- Yo antibodies was confirmed by immunofluorescence assay and by Western blot analysis against both Purkinje cell lysates and the CDR62 fusion protein. Yo antigen was demonstrated in sections of the patient's tumor. Antibody ti ters fell after tumor removal. Transitional cell carcinoma should be consid ered in patients presenting with subacute cerebellar degeneration and anti- Yo antibody response in whom ovarian, adnexal, uterine, or breast cancer ca nnot be detected.