Paraneoplastic Motor Neuropathy in Nodular Sclerosis Hodgkin's Lymphoma: Case Report

Paraneoplastic neurological syndromes (PNS) are an uncommon complication of malignancy, characterized by autoantibody generation against neuronal structures, causing a spectrum of neurological syndromes affecting the central, peripheral, and/or autonomic nervous systems. PNS in lymphoma is exceedingly rare and there is limited evidence on the features, incidence, and severity of these neurological sequelae secondary to malignancy. Here, we report on a case of isolated diffuse motor neuropathy secondary to underlying nodular-sclerosis classical Hodgkin's lymphoma (cHL) in a 71-year-old male. This patient initially presented to the hospital with 3 months of progressive generalized weakness, weight loss, gait instability, and a rash. A broad workup revealed evidence of diffuse lymphadenopathy, which was characterized as nodular-sclerosis cHL on biopsy. Concurrent neurological workup demonstrated generalized axonal motor neuropathy on nerve conduction studies with negative serologies for a panel of paraneoplastic autoantibodies, but positive Asialo-GM1 titers, a marker of autoimmune myopathy. The patient was initiated on doxorubicin, vinblastine, and dacarbazine (AVD) for their lymphoma and received two doses of IVIg for their motor neuropathy, which did not reoccur. The patient was transitioned to brentuximab + nivolumab for 4 cycles, followed by nivolumab + AVD for 6 cycles with a complete response and no evidence of disease. Asialo-GM1-associated isolated diffuse motor neuropathy in Hodgkin's lymphoma has not been previously reported in the literature. In this case report, we review the 2021 updated diagnostic criteria for the diagnosis of paraneoplastic neurological syndromes in the context of this patient presentation to highlight an instance where these guidelines do not fully capture the wide spectrum of PNS.