Necrotizing brainstem leukoencephalopathy six weeks following radiotherapy

Area of Science:

• Neurology
• Radiation Oncology
• Pathology

Background:

• Pituitary macroadenomas can cause significant mass effect.
• Radiotherapy is a treatment option for pituitary adenomas, particularly those unresponsive to medication or surgery.
• Understanding the risks and timelines of radiation-induced injury is crucial for patient management.

Observation:

• A 71-year-old male received peripituitary radiotherapy for a null cell pituitary macroadenoma.
• Six weeks post-treatment, the patient experienced rapid onset of severe neurological symptoms including vision loss, diplopia, ataxia, cranial nerve palsy, somnolence, and respiratory distress.
• These deficits were fixed and ultimately required life support, leading to death within one year.

Findings:

• Autopsy revealed extensive brainstem necrosis with dystrophic axonal calcification.
• Mild focal vascular hyalinization was noted, but without evidence of fibrinoid necrosis, telangiectasias, or large vessel abnormalities.
• The pathological findings are consistent with an unusual case of early delayed radiation injury.

Implications:

• This case highlights the potential for severe, early-onset delayed radiation injury following pituitary radiotherapy.
• The findings underscore the importance of recognizing and monitoring for delayed neurological complications after radiation treatment.
• Further research into the mechanisms and risk factors for early delayed radiation injury is warranted to improve patient outcomes.