Radiation-Associated Angiosarcoma as a Presentation of Disease Progression in a Patient on Immunotherapy for Metastatic Non-small Cell Lung Cancer

Non-small cell lung cancer (NSCLC) is the dominant form of lung cancer, comprising around 85% of cases. Stage 4 NSCLC has a grim prognosis; however, immunotherapy and radiation therapy have become vital treatments for advanced-stage NSCLC, despite the risk of inducing a second primary malignancy. This case report focuses on a 45-year-old female diagnosed with NSCLC and metastasis to the 11th thoracic vertebral body. After various treatments, including radiation, a potential radiation-associated secondary malignancy, epithelial angiosarcoma, was discovered. Following treatment modification, the patient achieved complete metabolic remission, highlighting the importance of clinicians being cautious about secondary primary cancers in NSCLC patients with a history of radiation therapy. Accurate diagnosis through biopsy and continuous surveillance are essential in managing NSCLC patients effectively.