大腸鋸歯状病変に対する内視鏡治療の進歩

Advances in Endoscopic Treatment of Colorectal Serrated Lesions

要旨●大腸癌発生過程としてserrated pathwayが新たに提唱され，大腸鋸歯状病変は大腸癌の前駆病変の一つとして注目を集めるようになってから久しい．検出された腺腫への内視鏡切除が大腸癌発症および癌死を抑制するのと同様に，大腸鋸歯状病変の内視鏡切除もその効果が期待されている．しかし，同病変に対する内視鏡切除の適応や切除手技の選択に関する各診療ガイドラインは，十分なエビデンスがない中で作成されており，内視鏡切除後サーベイランスに関する見解も十分ではない．本稿では，SSLを中心とした大腸鋸歯状病変に対する内視鏡切除の現状と筆者らの方針を述べたが，さらなる病態解明と内視鏡切除の大規模前向きコホート研究の実施およびその結果が望まれる．

　The “serrated pathway” has been proposed as the process by which colorectal cancer develops, and serrated lesions of the colorectum are one of the precursor lesions. Just as the endoscopic resection of colorectal adenomas reduces the incidence and mortality of colorectal cancer, endoscopic resection of serrated lesions may produce a preventive effect. However, clinical guidelines regarding the indications and technique for endoscopic resection of serrated lesions have been developed with limited evidence. Furthermore, there is a lack of consensus regarding post-endoscopic resection surveillance. In this review article, we have described the current state of endoscopic resection of colorectal serrated lesions, specifically sessile serrated lesions, and have outlined our approach. Further elucidation of the pathology and the implementation and outcomes of endoscopic resection in large-scale prospective cohort studies are required.