Diffuse large B-cell lymphoma presenting with neurolymphomatosis and intravascular lymphoma: a unique autopsy case with diverse neurological symptoms

A 78-year-old Japanese male noticed a difficulty in the beginning of standing up, followed by 7a progressive numbness of extremities with pain, Bell’s palsy, dysarthria, and difficulty in swallowing. A clinician had suspected cancer of unknown primary origin, accompanied by the diverse and elusive neurological symptoms, likely presenting as painful mononeuropathy simplex and cranial neuropathy. He developed dysbasia over weeks and died 1 month after the symptom onset. At autopsy, an ill-defined large and soft tumor mass in the right lobe of the liver with direct invasion into the right adrenal gland was observed. The left adrenal gland or right iliopsoas muscle was also involved. Microscopic findings showed a monotonous proliferation of medium-sized to large atypical lymphoid cells, which were diffusely positive for CD20 in immunohistochemistry, consistent with diffuse large B-cell lymphoma (DLBL). Furthermore, the lymphoma cells aggressively infiltrated endoneurial and subperineurial spaces not only in the peripheral nerves and plexuses, but partly in the spinal nerve roots, and intravascular spaces in various tissues. Therefore, systemic lymphoma (DLBL) complicated with neurolymphomatosis (NL) and intravascular lymphoma (IVL) was diagnosed. Very early diagnosis and treatment are necessary for the NL patients with poor prognosis.