Clinical, serological, and electrophysiological differences in chronic inflammatory demyelinating polyradiculoneuropathy patients with and without malignancy - real-life evidence.

INTRODUCTION

Malignancies may coexist in patients with chronic inflammatory demyelinating polyradiculoneuropathy (CIDP), possibly indicating shared immune mechanisms or risk factors. This study aimed to assess the frequency of cancer in patients with CIDP and the clinical characteristics of CIDP subgroups with and without cancer.

MATERIAL AND

METHODS

The study included 61 patients with CIDP (mean age 61.6 ± 11.8 years). Cancer was diagnosed after CIDP in 14 cases (23%). Diagnostic parameters: clinical, biochemical and electrophysiological, and their correlations were analyzed in patients with and without cancer.

RESULTS

At chronic inflammatory demyelinating polyradiculoneuropathy diagnosis, the mean inflammatory neuropathy cause and treatment (INCAT) score was 2.29 ± 1.68 in the cancer group and 2.21 ± 1.81 in the non-cancer group (p = 0.891). At cancer diagnosis, the scores were 2.79 ± 1.81 vs. 2.40 ± 1.73, respectively (p = 0.489). Immunoglobulin levels were more variable in cancer patients, especially immunoglobulin M (IgM), although the differences were not significant. Cerebrospinal fluid (CSF) protein levels averaged 102.04 mg/dL in cancer patients and 92.67 mg/dL in those without cancer. In CIDP patients with cancer, a strong negative correlation was found between peroneal nerve motor latency and the INCAT score (r = -0.58). In those without cancer, CSF protein levels positively correlated with compound muscle action potentials (CMAP) latency and negatively with conduction velocity in both the ulnar and peroneal nerves.

CONCLUSIONS

While not statistically significant, trends indicate that malignancy in CIDP may be linked to a more aggressive disease course, distinct immune profiles, and alternative pathogenic mechanisms, warranting further investigation into targeted therapies.