Value of nerve biopsy in patients with latent malignant hemopathy and peripheral neuropathy: a case series

Abstract

Hematological malignancies include several diseases that may affect the peripheral nervous system (PNS) through various mechanisms. A common and challenging situation is represented by the occurrence of an active peripheral neuropathy in a patient with a supposed inactive hematological disorder.We report clinical, electrophysiological, biological, and pathological data of 8 patients with latent malignant hemopathies (most were considered in remission): B-cell chronic lymphocytic leukemia in 3 patients, B-cell lymphoma in 1 patient, low-grade non-Hodgkin's lymphoma in 1 patient, Waldenström's macroglobulinemia in 1 patient, smoldering multiple myeloma in 1 patient, and monoclonal gammopathy of undetermined significance in 1 patient.In all these cases, the nerve biopsy (NB) helped to diagnose the hematological relapse or detect a pathological mechanism linked to the hematological disorder: epineurial lymphocytic infiltration in 5 patients (including one with antimyelin-associated glycoprotein antibodies), cryoglobulin deposits in 1 patient, chronic inflammatory demyelinating polyneuropathy in 1 patient, and necrotizing vasculitis in 1 patient. In each case, pathological findings were crucial to select the adequate treatment, leading to an improvement in the neurological and biological manifestations.These observations illustrate the value of NB and the need for active collaboration between neurologists and hematologists in such cases.

FIGURE 1

(A) Frozen transverse section of the sural nerve of patient 1 stained with anti-CD20 antibody. Several vessels in the epineurium are surrounded by B-cell infiltrates. (B) Electron micrograph of tranverse section of the sural nerve of patient 1 showing the typical widening of the most external myelin lamellae. (C) Immunoelectron micrograph of patient 2. Anti-kappa light chain immunogold staining shows that the monoclonal protein of the patient has infiltrated the myelin sheath. (D) Frozen transverse section of the sural nerve of patient 3 stained with anti-CD20 antibody. There is a massive infiltrate of B-cells in the epineurium.

FIGURE 2

(A) Paraffin-embedded transverse section of the sural nerve of patient 4 stained with hematxylin-eosin, showing perivascular infiltrate of mononuclear cells in the epineurium. (B) Paraffin-embedded longitudinal section of the radial nerve of patient 5, showing massive infiltrates of mononuclear cells in the epineurium. (C) Frozen tranverse section of the sural nerve of patient 7 stained with anti-CD45 antibody, showing a perivascular epineurial T-cell infiltrate. (D) Paraffin-embedded transverse section of the sural nerve of patient 8, stained with hematoxylin-eosin. Two middle-size vessels of the epineurium display the typical aspect of necrotizing vasculitis.