结直肠无蒂锯齿状病变的诊疗进展

A Review of Progress in Diagnosis and Therapy of Colorectal Sessile Serrated Lesions

摘要: 结直肠无蒂锯齿状病变是结直肠癌锯齿状通路的关键前驱病变，具有高度恶变潜能，是导致间期结直肠癌的重要原因，近年来临床重要性日益凸显。因此，本文系统综述了无蒂锯齿状病变的最新研究进展。在分子层面，其特征主要为BRAF突变、CpG岛甲基化表型和微卫星不稳定性；在诊断方面，其内镜下常表现为扁平、边界不清、覆盖黏液帽的形态，诊断挑战巨大，而窄带成像、联动彩色成像等图像增强内镜以及新兴的人工智能技术有望显著提升其检出率与诊断准确性。在治疗上，应根据病变大小个体化选择切除方式，如冷圈套息肉切除术适用于<10 mm的病变，内镜下黏膜切除术及其衍生技术适用于更大病变，内镜下黏膜剥离术则用于复杂疑难病例。术后需根据病变大小、数量及是否伴异型增生制定风险分层随访策略。未来研究需致力于深化无蒂锯齿状病变的分子机制探索、优化内镜诊疗技术并推动人工智能的临床整合、规范切除后随访，从而最终有效降低由其引发的结直肠癌负担。

Abstract: Colorectal sessile serrated lesions are critical precursor lesions in the serrated pathway of colorectal cancer, characterized by high malignant potential and recognized as a significant cause of interval colorectal cancer. Their clinical importance has become increasingly prominent in recent years. Therefore, this article provides a systematic review of the latest research advances in sessile serrated lesions. At the molecular level, sessile serrated lesions are primarily characterized by BRAF mutations, the CpG island methylator phenotype, and microsatellite instability. Regarding diagnosis, sessile serrated lesions often present endoscopically as flat, ill-defined lesions covered by a mucus cap, posing significant diagnostic challenges. However, image-enhanced endoscopic techniques such as narrow-band imaging and linked color imaging, along with emerging artificial intelligence technologies, show great promise in significantly improving their detection rate and diagnostic accuracy. For treatment, the choice of resection technique should be individualized based on lesion size. Cold snare polypectomy is suitable for lesions <10 mm, endoscopic mucosal resection and its derivatives for larger lesions, and endoscopic submucosal dissection for complex and difficult cases. Postoperative risk-stratified follow-up strategies should be established based on lesion size, number, and the presence of dysplasia. Future research should focus on elucidating the molecular mechanisms of sessile serrated lesions, optimizing endoscopic diagnosis and treatment techniques, promoting the clinical integration of artificial intelligence, and standardizing post-resection follow-up. These efforts are essential to ultimately reduce the burden of colorectal cancer attributable to these lesions.