Department of Medical and Surgical Sciences, S. Orsola-Malpighi Hospital, University of Bologna, Bologna, Italy.
Digestive Endoscopy Unit, Division of Gastroenterology, Humanitas Research and University Hospital, Rozzano, Italy.
Gut. 2018 Aug;67(8):1464-1474. doi: 10.1136/gutjnl-2017-315103. Epub 2017 Dec 5.
Endoscopic submucosal dissection (ESD) aims to achieve en bloc resection of non-pedunculated colorectal adenomas which might be indicated in cases with superficial submucosal invasive cancers (SMIC), but the procedure is time consuming and complex. The prevalence of such cancers is not known but may determine the clinical necessity for ESD as opposed to the commonly used piecemeal mucosal resection (endoscopic mucosal resection) of colorectal adenomas. The main aim was to assess the prevalence of SMIC SM1 (ie, invasion ≤1000 µm or less than one-third of the submucosa) on colorectal lesions removed by ESD.
A literature review was conducted using electronic databases (up to March 2017) for colorectal ESD series reporting the histology of the dissected lesions.
51 studies with data on 11 260 colorectal dissected lesions were included. Most resected lesions (82.2%; 95% CI 78.8% to 85.3%) were adenomas (low- and high-grade dysplasia, 26.8% and 55.4%, respectively). Overall, 15.7% were submucosal cancers, but only slightly more than half (8.0%; 95% CI 6.1% to 10.3%) had an infiltration depth of ≤1000 µm, providing a number needed to treat (NNT) to avoid one surgery of 12.5. Estimating an oncologically curative (R0; G1/2; L0/V0) resection rate of 75.3% (95% CI 52.2% to 89.4%) for malignant lesions, the prevalence of curative resection lowered to 6% (95% CI 4.2% to 7.2%) with an NNT of 16.7.
The low prevalence of SMIC SM1 in lesions selected for ESD as well as the even lower rate of curative resection limits the clinical applicability of endoscopic en bloc resection. This calls for caution over an indiscriminate use of this technique in the resection of colorectal neoplasia.
内镜黏膜下剥离术（ESD）旨在整块切除非息肉状结直肠腺瘤，对于浅层黏膜下浸润癌（SMIC）患者可能需要进行这种手术，但该手术耗时且复杂。目前尚不清楚这类癌症的患病率，但它可能决定了 ESD 的临床必要性，而非通常使用的结直肠腺瘤分片黏膜切除术（内镜黏膜切除术）。本研究的主要目的是评估 ESD 切除的结直肠病变中 SMIC SM1（即浸润深度≤1000μm或小于黏膜下三分之一）的患病率。
对截至 2017 年 3 月的电子数据库中有关结直肠 ESD 系列报告的研究进行文献复习，以评估其组织学特征。
纳入了 51 项研究，共涉及 11260 例结直肠内镜下剥离病变。大多数切除的病变（82.2%；95%可信区间 78.8%至 85.3%）为腺瘤（低级别和高级别异型增生分别为 26.8%和 55.4%）。总体而言，15.7%为黏膜下癌，但仅有略多于一半（8.0%；95%可信区间 6.1%至 10.3%）的浸润深度≤1000μm，需要治疗 12.5 例患者才能避免一次手术。对于恶性病变，估计有 75.3%（95%可信区间 52.2%至 89.4%）的患者能获得治愈性（R0；G1/2；L0/V0）切除，当把治疗终点定义为治愈性切除（SMIC SM1）时，其患病率降至 6%（95%可信区间 4.2%至 7.2%），需要治疗 16.7 例患者。
在选择进行 ESD 的病变中，SMIC SM1 的低患病率，以及较低的治愈性切除率，限制了内镜整块切除术的临床应用。这表明在结直肠肿瘤的切除中，应慎重考虑这种技术的盲目使用。
