Once a remedy, later a disease

Radiation-induced lung injury (RILI) encompasses any lung toxicity induced by radiation therapy (RT). It manifests acutely as radiation pneumonitis (RP) and chronically as radiation pulmonary fibrosis. It is usually seen in patients who have undergone thoracic irradiation for the treatment of lung, breast, or hematologic malignancies. The volume of lung irradiated and the mean lung dose are important risk factors. The diagnosis is usually based on a combination of typical symptoms (e.g., cough, dyspnea, and occasionally fever), timing, dose, and location of radiation therapy, compatible imaging findings, and exclusion of other causes. We report a case of a patient with breast cancer, who had received locoregional radiotherapy (RT) and then palliative RT for metastasis in the rib, following which she developed symptoms and radiological manifestations consistent with RILI. The patient recovered clinically and radiologically with conservative management. It was important to accurately diagnose the entity early since RP with moderate-to-severe symptoms and impaired respiratory function needs to be treated early to prevent irreversible lung damage.