Radiation Pneumonitis
Acute inflammatory lung reaction following thoracic radiation therapy, typically occurring 1-6 months post-treatment.
Full Definition
Radiation pneumonitis is an acute inflammatory condition of the lungs that develops as a consequence of thoracic radiation therapy, typically manifesting 1-6 months after treatment completion. The condition is characterized by inflammation of the alveoli and interstitial tissues within the radiation field, presenting clinically with dyspnea, cough, and radiographic changes. Risk factors include larger lung volumes receiving high doses, concurrent chemotherapy, and pre-existing lung disease. Severe cases may progress to radiation fibrosis, making dose-volume constraints for lung tissue critical in treatment planning.
Usage
Usage note: Distinguish from chronic radiation fibrosis which develops later.
In Context
- "The patient developed grade 2 radiation pneumonitis requiring corticosteroid therapy." — Toxicity assessment report
- "Treatment planning constraints limited mean lung dose to reduce radiation pneumonitis risk." — Plan evaluation summary