切除不能Ⅲ期非小細胞肺癌における化学放射線療法

Radiotherapy for unresectable stage Ⅲ non-small cell lung cancer

切除不能Ⅲ期非小細胞肺癌（non-small cell lung cancer：NSCLC）に対する現在の標準治療は化学放射線療法である。かつて予後不良の代表とされていた肺癌は，免疫療法や分子標的薬をはじめとする新規薬剤の開発と臨床導入により，近年大きく予後が改善している。これに伴い，切除不能Ⅲ期NSCLCの治療における放射線治療の位置づけや役割も，この数年間で急速に変化しつつある。

The PACIFIC trial showed that consolidation durvalumab after concurrent chemoradiotherapy prolongs overall survival in unresectable stage Ⅲ non-small cell lung cancer（NSCLC）, changing clinical practice. The LAURA trial found that in unresectable stage Ⅲ EGFR-mutant NSCLC, osimertinib improved progression-free survival, indicating that molecularly targeted strategies in stage Ⅳ NSCLC are now being introduced in stage Ⅲ NSCLC as well. Reducing toxicity after chemoradiotherapy has become increasingly critical：pulmonary toxicity was the most important adverse event and the main reason patients cannot proceed to consolidation therapy. Recently, concerns about cardiotoxicity has also increased. These consolidations have driven wider adoption of IMRT to decrease toxicities. With advances such as machine learning-assisted treatment planning, adaptive radiotherapy, and high-precision particle therapy, further improvement in loco-regional control and safety are expected.