Paraneoplastic Yo Syndrome

Case Study A
A 65-year-old woman noted diplopia and an unsteady gait. Over a three-month period the symptoms progressed to where she could not walk without support and was forced to give up her hobby of painting because of incoordination of her hands. She had difficulty feeding herself without spilling food. She developed dysarthria sufficient to make it hard for people to understand her and she could not read or watch television easily because the images appeared to "jump."

Neurological evaluation revealed downbeating and lateral nystagmus, upper and lower extremity ataxia, and dysarthria. The remainder of the neurological examination was normal. Mammography was negative. CT and sonography of the pelvis were normal. Serum CA-125 was also normal. Colonoscopy revealed several polyps in the colon which were biopsied. One showed a well-differentiated adenocarcinoma arising in a tubulovillus adenoma. Despite the finding of cancer in the colon, the presence of the Yo autoantibody strongly suggested that she suffered paraneoplastic cerebellar degeneration associated with breast or gynecologic cancer. The patient underwent a D&C followed by total abdominal hysterectomy and bilateral salpingo-oophorectomy. The ovaries, uterus, and fallopian tubes appeared grossly normal. Frozen section analysis of left adenexal structures revealed an adenocarcinoma. The final histologic diagnosis was of a poorly differentiated adenocarcinoma limited to the left mesovarium.