Hodgkin Lymphoma With Diplopia and Nystagmus: A Paraneoplastic Cerebellar Degeneration With Ectopic Expression of DNER Antigen on Reed-Sternberg Cells.

Abstract Paraneoplastic neurological syndromes (PNS) are a wide spectrum of diseases characterized by an immune disregulation that lead to nervous tissue damage driven by the presence of concomitant neoplasm. In fact, PNS are usually accompanied by the presence of antibodies against some antigens (so called onconeural) that usually exhibit ectopic expression by neoplastic cells. In the case of Hodgkin's lymphoma, the most common subtype of PNS are paraneoplastic cerebellar degenerations (PCDs), the majority of which is linked to liquoral or serological detection of antibodies against DNER antigen (previously known as anti-Tr antibodies). In this setting, the neoplastic ectopic expression has always played a marginal role according to previous literature. Here we report a case of HL with clinico-radiological evidence of PCD, serological detection of anti-DNER antibodies and ectopic cytoplasmatic expression of DNER antigen at level of Reed-Sternberg cells. This exceptionality could provide the basis for further investigation aimed at deepen the pathogenesis of these particular paraneoplastic neurological syndromes considering the complex HL-related microenvironment.