A 70-year-old man having a mass lesion on his right lower abdomen for 2 months was admitted to our hospital for diagnosis. Upon admission, the patient experienced bilateral upper and lower limb weakness, which aggravated. He underwent nerve conduction study and was diagnosed with axonal neuropathy. Diagnosis of diffuse large B-cell lymphoma (DLBCL) was accomplished via biopsy of the mass lesion, with positive laboratory tests for anti-ganglioside antibodies. Based on these results, immune-mediated DLBCL-induced polyneuropathy was suspected, and chemotherapy (R-CHOP) was immediately started. Limb weakness improved and completely resolved. After six courses of R-CHOP, no evidence of DLBCL was observed on PET/CT (i.e., complete metabolic remission). The patient lived without DLBCL relapse or neurological symptoms after remission. Only few reports regarding immune-mediated polyneuropathy induced by malignant lymphoma are available in the literature, which, together with this case, suggest that prompt control of malignant lymphoma is crucial for favorable prognosis of neuropathy.
Keywords: Anti-ganglioside antibody; Diffuse large B-cell lymphoma; Guillain-Barre syndrome; Paraneoplastic neuropathy.