Neurolymphomatosis in a patient with extranodal NK/T-cell lymphoma, nasal-type: a case report and literature review.

A 47-year-old man presented with a fever and lower extremity paresthesia. A physical examination revealed sensory deficits in the left hand, distal arm and right sole. A bone marrow aspiration demonstrated infiltration of extranodal NK/T-cell lymphoma, nasal type, and (18)F-fluoro-2-deoxyglucose positron emission tomography (FDG-PET) disclosed extensive involvement of the peripheral nerves. These findings were consistent with a diagnosis of neurolymphomatosis (NL). The lymphoma progressed soon after the patient underwent cord blood transplantation, and he died on day 33 after transplantation. NL is a rare manifestation of lymphoma characterized by infiltration of the peripheral nerves, leading to neuropathy. It is an increasingly recognized entity and can be the first indication of lymphoma.