[A case of neurolymphomatosis: peripheral neuropathy induced by diffuse large B-cell lymphoma without any abnormal accumulation observed on early positron emission tomography-computed tomography].

A 64-year-old woman with diffuse large B-cell Lymphoma (DLBCL) complained of double vision and pain sensation in her limbs after eight cycles of chemotherapy. F-fluorodexyglucose-positron emission tomography (FDG-PET) 7 days after the onset of double vision showed no abnormal accumulation and confirmed remission of DLBCL according to the international criteria. However, she developed limb weakness and severe paresthesia. The second FDG-PET 41 days after onset showed increased uptake at the both the brachial and lumbar plexuses, suggesting neurolymphomatosis. Although FDG-PET appears to be a highly sensitive diagnostic method for neurolymphomatosis, it is sometimes difficult to detect neurolymphomatosis in early diagnose, such as with this case. Therefore, multiple examinations are necessary to determine neurolymphomatosis.