食道SM癌の治療選択—根治的CRTの立場から

Treatment Options for Esophageal Submucosal Cancer, from the Viewpoint of Curative CRT

要旨●cStage I（cT1b）食道癌に対する根治的化学放射線療法（CRT）は，標準治療である外科的切除術を行わない場合に食道温存を図ることができる治療選択肢として食道癌診療ガイドラインで推奨されている．近年報告されたJCOG0502の結果，5年生存割合は食道切除術と差はなく，根治的CRTの大きな利点である5年食道温存生存割合が80.4%であることがわかった．課題として遅発性有害事象を増加させることなく，所属リンパ節領域の再発抑制が挙げられる．現在，予防的リンパ節領域照射（JCOG1904），強度変調放射線治療，陽子線治療や重粒子線治療などの粒子線治療，新規抗癌薬併用の治療開発が行われている．

　Definitive chemoradiotherapy for managing cStage I（cT1b）esophageal cancer is recommended in the esophageal cancer practice guidelines as a treatment option for preserving the esophagus in the absence of surgical resection, which is the standard treatment. The recently reported results of JCOG0502 demonstrated that the 5-year survival rate of those receiving definitive chemoradiotherapy was no different from that of patients undergoing esophagectomy. The 5-year esophageal preservation survival rate was 80.4%, a major advantage of definitive chemoradiotherapy. However, the challenge is to prevent the regional recurrence without increasing the number of late adverse events. Elective nodal irradiation（JCOG1904）, intensity-modulated radiotherapy, particle therapies such as proton beam therapy and carbon-ion beam therapy, and the combined use of novel anticancer agents are currently being explored.