Radiation-induced acute pericarditis after palliative spine radiation in a non-small cell lung cancer patient on osimertinib: a case report

Radiation-induced acute pericarditis is a rare but life-threatening condition requiring prompt recognition. We report a case of acute pericarditis occurring immediately after palliative spine radiation in a 54-year-old male with non-small cell lung cancer (NSCLC) on Osimertinib. He initially presented with brain, liver, spleen, and bone metastases and was treated with erlotinib and whole-brain radiation. Disease progression prompted a switch to Osimertinib and palliative spine radiation for spinal cord compression. Two days post-radiotherapy, he developed acute chest pain, diagnosed as radiation-induced pericarditis, possibly exacerbated by Osimertinib. Symptoms improved with aspirin and colchicine, and Osimertinib was safely resumed. This case highlights the importance of early recognition of radiation-induced pericarditis, particularly in patients receiving concurrent thoracic radiation and Osimertinib, to ensure timely management and prevent complications.