The inflammatory response from stereotactic body proton therapy versus stereotactic body radiation therapy: implications from early stage non-small cell lung cancer

Abstract

Lung cancer is the second most common noncutaneous cancer and the deadliest cancer in the United States (US) with 228,150 estimated new cases in 2019 (1). About 87% of lung cancers diagnosed in the US are non-small cell lung cancer (NSCLC), which currently has a 5-year overall survival (OS) rate of 23% across all stages, ranging from 57% for stage I to 4% for stage IV diseases (2). Radiation therapy (RT) is heavily utilized in the treatment of NSCLC. In early stage NSCLC (ES-NSCLC), stereotactic body radiation therapy (SBRT) delivered with photon radiotherapy has been shown to have high a local control rate and low incidence of severe treatment related toxicities (3), making it a standard of care curative option especially in medically inoperable patients (4). In stage III or locally advanced NSCLC (LA-NSCLC), radiation is used in approximately 60% of cases, often as part of bimodality treatment in conjunction with chemotherapy or as part of trimodality treatment delivered concurrently with chemotherapy followed by surgical resection (2). In stage IV or metastatic NSCLC, radiation is being increasingly used to palliate symptomatic lung or distant metastases and in specific settings, such as oligometastatic NSCLC, may be utilized with curative intent to target both the primary tumor and all metastatic disease sites (5)