[Paraneoplastic cerebellar degeneration as initial presentation of a pancreatic small-cell carcinoma]

Oat (small) cell carcinoma is the type of tumour most frequently associated to neurologic paraneoplastic syndromes. It is usually located in the lungs although it has been described in some other locations. Cerebellar symptoms may appear alone, associated to anti Yo antibodies ( Breast and gynaecologic carcinomas), or as manifestation of a more generalized paraneoplastic encephalopathy, associated to signs and symptoms of some other neurologic systems affected.

A 52 year old patient consulted due to a pancerebellar clinical picture, which started about two months before, and later associated to polineuropathy. Abdominal CT showed a 4 cm mass in the head of the pancreas. Pathologic evaluation demonstrated a poorly differentiated small cell pancreatic tumour. Anti Hu antibodies in high titres were found both in serum and cerebrospinal fluid.

The association of anti Hu immunity and paraneoplastic encephalomyelitis has been observed in patients with neuroblastoma, seminomas, colorectal, breast and prostate carcinomas and some types of sarcoma. Only about 1% of pancreatic malignancies correspond to small cell type. We have not found any previous report about the association between a paraneoplastic syndrome and pancreatic poorly differentiated small cell carcinoma.