Bortezomib-induced motor neuropathy: A case report

Area of Science:

• Oncology
• Neurology
• Pharmacology

Background:

• Bortezomib is a proteasome inhibitor utilized in treating multiple myeloma and certain lymphomas.
• Common bortezomib adverse effects include fatigue, thrombocytopenia, GI issues, and sensory peripheral neuropathy.
• This report details a rare instance of motor neuropathy following bortezomib treatment.

Observation:

• An 87-year-old male with multiple myeloma developed severe lower extremity weakness after five cycles of bortezomib, dexamethasone, and lenalidomide (VRd).
• Electromyography confirmed a demyelinating polyneuropathy with active denervation, attributed to bortezomib.
• Neuropathy symptoms persisted after bortezomib discontinuation.

Findings:

• The patient's motor neuropathy gradually resolved with steroids and intravenous immunoglobulin (IViG).
• Restarting lenalidomide and dexamethasone alone did not cause recurrence of the neuropathy.
• This suggests bortezomib as the likely causative agent for the motor neuropathy.

Implications:

• Clinicians should be vigilant for bortezomib-induced motor neuropathy, especially in older patients or those with pre-existing neuropathy.
• Prompt monitoring, dose modification, or discontinuation of bortezomib may be necessary.
• Treatment with steroids or IVIG can be effective in managing bortezomib-induced motor neuropathy.