Bilateral phrenic nerve dysfunction: a late complication of mantle radiation

Area of Science:

• Neurology
• Oncology
• Radiotherapy

Background:

• Neurologic complications from radiotherapy can manifest immediately or years later.
• Brachial plexus neuropathy is a known complication of radiotherapy to supraclavicular and axillary lymph nodes.
• Phrenic nerve dysfunction is an uncommon but reported complication associated with radiation-induced brachial neuropathy.

Observation:

• This report details a patient who developed asymmetric diaphragmatic weakness.
• The weakness resulted from phrenic nerve paralysis, occurring 37 years post-mantle radiation for Hodgkin lymphoma.
• The patient presented without concurrent brachial plexus neuropathy or phrenic nerve involvement from secondary malignancy.

Findings:

• The patient's diaphragmatic weakness was attributed to radiation-induced phrenic nerve injury.
• This case represents a very late-onset neurologic complication of radiotherapy.
• The absence of brachial plexus involvement or malignancy suggests isolated phrenic nerve damage.

Implications:

• This case underscores the potential for extremely delayed neurologic sequelae from radiotherapy.
• It highlights the importance of considering radiation-induced nerve injury in patients with unexplained diaphragmatic dysfunction long after cancer treatment.
• Further investigation into the mechanisms of late-onset radiation-induced neuropathies is warranted.