Abstract
A 31-year-old man presented with a subacute cerebellar syndrome of unknown aetiology. Investigations including a paraneoplastic antibody screen were negative and a working diagnosis of possible vasculitis was concluded. After 1 month, he re-presented with worsening of his symptoms and a neck lump. He was diagnosed with anaplastic lymphoma kinase, negative non-Hodgkin's lymphoma and paraneoplastic cerebellar syndrome. A more extensive paraneoplastic antibody screen found patient to be Tr (delta/notch-like epidermal growth factor-related receptor) antibody positive. After a period of chemotherapy and steroid treatments, his symptoms are now stable in terms of cerebellar function. This case report summarises a very rare diagnosis of paraneoplastic cerebellar degeneration with a positive onconeuronal antibody associated with anaplastic non-Hodgkin's lymphoma.