内镜黏膜下剥离术后食管狭窄的防治研究进展

正华中科技大学同济医学院附属同济医院丁强田德安*,武汉430030     

激素预防食管早癌内镜黏膜下剥离术后食管狭窄效果的Meta分析

目的探讨激素预防食管早癌内镜黏膜下剥离术(ESD)术后食管狭窄的效果。 方法检索截止2017年11月发表在CBM、Pubmed、Embase、Cochrane Library数据库中有关激素预防食管早癌ESD术后食管狭窄效果的相关研究,采用RevMan5.3软件对数据进行Meta分析。 结果共有12项研究535例患者纳入分析。Meta分析结果显示,局部注射激素可降低食管早癌ESD术后食管狭窄发生率(RR＝0.41,95%CI：0.27～0.63,P<0.0001),口服激素可降低非全环周ESD术后食管狭窄发生率(RR＝0.25,95%CI：0.11～0.54,P＝0.000 4),而对于降低全环周ESD术后食管狭窄发生率无明显效果(RR＝0.54,95%CI：0.16～1.84,P＝0.33)。口服激素(RR＝－10.73,95% CI：－15.47～－5.98,P<0.0001)和局部注射激素(RR＝－3.22,95% CI：－5.11～－1.34,P＝0.0008)均可减少食管狭窄后EBD扩张次数。 结论激素对于预防食管早癌ESD术后的食管狭窄是安全有效的;口服激素可以降低非全环周ESD术后食管狭窄的发生率,但对于预防全环周ESD术后食管狭窄无明显效果;口服激素和局部注射激素均可以减少ESD术后食管狭窄的EBD扩张次数,并且口服激素减少的效果优于局部注射激素。     

老年食管早癌内镜黏膜下剥离术后狭窄的高危因素分析

[目的]分析食管早癌内镜黏膜下剥离术后狭窄的高危因素。[方法]选择行内镜黏膜下剥离术治疗的老年食管早癌患者239例,观察内镜黏膜下剥离术后狭窄发生情况。对患者性别、年龄、病变分型、操作时间、糖尿病史、高血压史、吸烟史、饮酒史、病灶部位、病变直径、病变形态、浸润深度、血小板淋巴细胞比值(PLR)、中性淋巴细胞比值(NLR)与术后狭窄的关系采用多因素Logistic回归分析。[结果]239例中术后狭窄37例(狭窄组),发生率为15.48%;202例属无狭窄组。经单因素分析表明,狭窄组与无狭窄组性别、年龄、病变分型、操作时间、糖尿病史、高血压史、吸烟史、饮酒史、病灶部位和浸润深度比较差异无统计学意义(P>0.05);狭窄组与无狭窄组病变直径、病变深度、PLR和NLR比较差异有统计学意义(P<0.05)。经多因素Logistic回归分析显示,病变直径>5 cm、病变深度m3+sm、高PLR和高NLR为影响术后狭窄高危因素。[结论]食管早癌内镜黏膜下剥离术后狭窄发生率较高,其中病变直径>5 cm、病变深度m3+sm、高PLR和高NLR为其高危因素。     

内镜黏膜下剥离术后食管狭窄预防的研究进展

内镜黏膜下剥离术(ESD)是治疗食管黏膜良恶性病变的常用手段,已成为食管癌前病变和早期食管癌的首选治疗方法.早期食管癌ESD术后5年生存率＞95％,但术后食管狭窄严重影响患者的生存质量.食管非环周病变切除后狭窄的发生率为56％～76％,环周病变切除后狭窄率更是高达100％.目前局部注射类固醇激素和口服类固醇激素是预防食...     

组织工程学方法在预防食管早癌内镜黏膜下剥离术后管腔狭窄中的应用

<正>内镜黏膜下剥离术(endoscopic submucosal dissection,ESD)能够对≥2cm消化道黏膜早癌进行整块切除,并获得准确的病理分期,目前已成为食管早癌及癌前病变的首选治疗方法。但对大面积食管黏膜早癌进行ESD可能存在一定的并发症,其中食管管腔狭窄是其中之一^[1-2]。     

内镜下经多隧道黏膜下剥离术和内镜黏膜下剥离术治疗消化道早癌及癌前病变的疗效及安全性

目的比较内镜下经多隧道黏膜下剥离术(ESMTD)和内镜黏膜下剥离术(ESD)治疗消化道早癌及癌前病变的疗效及安全性,探讨ESMTD和ESD在消化道早癌及癌前病变的治疗价值。方法选取消化道早癌及癌前病变患者140例。依据手术方式不同,分为ESMTD组(38例)和ESD组(102例)。比较两组术后病灶整块切除率、根治性切除率、操作时间、住院时间、并发症、疼痛程度及随访3、6、12个月的复发率、生活质量核心30问卷调查(QLQ-C30)评分。结果ESMTD组患者术后在整块切除率、根治性切除率明显高于ESD组,在操作时间、住院时间明、术后疼痛程度显著低于ESD组,差异有统计学意义(P<0.05)。ESMTD组术后并发症发生率显著低于ESD组,差异有统计学意义(P<0.05)。ESMTD组和ESD组在术后3个月均无复发病例,ESMTD组在术后6、12个月复发率低于ESD组,差异没有统计学意义(P>0.05);ESMTD组在术后3、6、12个月QLQ-C30量表评分均显著高于ESD组,差异有统计学意义(P<0.05)。结论ESMTD和ESD治疗消化道早癌及癌前病变疗效显著,且ESMTD在术后病灶整块切除率、根治性切除率、操作时间、住院时间、并发症、疼痛程度及复发率、QLQ-C30评分方面明显优于ESD,安全性较好。     

内镜黏膜下剥离术后食管狭窄的预防

内镜黏膜下剥离术（ESD）已成为食管早期肿瘤的标准治疗方法之一。随着治疗器械和操作技术的不断发展,ESD导致的出血及穿孔并发症也逐渐减少,但术后出现狭窄的概率仍较高。因此有必要分析ESD术后出现狭窄的原因,有针对性地提出预防措施,以此扩大食管ESD 的适应证,使大面积的食管浅表肿瘤能在内镜下被切除,且不引起食管狭窄。此文就目前各种预防ESD术后食管狭窄方法的机制及其优缺点作一综述。     

食管癌内镜黏膜下剥离术后激素预防狭窄

目的 探讨激素对食管癌内镜黏膜下剥离术(endoscopic submucosal dissection, ESD)后狭窄预防的疗效,同时评估激素的治疗方案,并确定狭窄的危险因素。方法 回顾性分析2018年3月至2022年8月于重庆医科大学附属第二医院因早期食管癌接受ESD治疗的56例患者,其食管黏膜周长缺损大于50%,但不累及全周。患者分为四组,包括单纯ESD组(n=13)、口服激素组(n=28)、激素注射组(n=10)和激素联合治疗组(n=5)。进行Logistic回归分析,以评估食管狭窄的危险因素。结果 单纯ESD组、口服激素组、激素注射组和激素联合治疗组的狭窄率分别为53.8%、17.9%、30.0%和20.0%。使用激素治疗患者的狭窄率明显低于单纯ESD组(20.9%vs 53.8%,P=0.035)。此外,口服激素组的狭窄率显著低于单纯ESD组(P=0.029)。多因素分析显示,食管黏膜周长缺损的程度是ESD后狭窄的重要危险因素(OR=20.67,95%CI:2.35～182.00,P=0.006)。使用激素(OR=0.14,95%CI:0.03～0.67,P=0.014)...     

食管全周浅表癌内镜黏膜下剥离术后长期保留胃管对食管狭窄的预防及治疗作用

为探讨食管全周浅表癌行内镜黏膜下剥离术（endoscopic submucosal dissection,ESD）后长期保留胃管对食管狭窄预防及治疗的影响,回顾性分析2018年1月—2021年12月在南京医科大学第一附属医院行ESD的食管全周浅表癌患者,术后置入胃管患者15例（胃管置入组）,无胃管置入患者23例（无胃管置入组）,比较两组患者基础情况、病变位置、病理分期、术后并发症、食管狭窄程度（进水情况）、疼痛情况、住院次数及医疗费用等资料。结果显示,两组患者在年龄、性别、病变位置及术后病理分期的构成方面差异无统计学意义（P>0.05）。与无胃管置入组相比,胃管置入组患者可进水率较高（11/15比6/23,P<0.05）,发生疼痛次数较少［（7.3±3.1）次比（10.7±3.6）次,t=3.00,P<0.05］,ESD后至食管支架置入前及置入后的住院次数和医疗总费用均明显低于无胃管置入组（P<0.05）。ESD后迟发性出血率、穿孔率以及首次狭窄出现时间,两组差异均无统计意义（P>0.05）。研究结果初步表明食管全周病变患者行ESD后长期保留胃管可减轻食管狭窄程度,具有较良好的安全性。     

糖皮质激素预防食管内镜黏膜下剥离术后狭窄的临床观察

目的评估口服醋酸泼尼松和口服醋酸泼尼松联合局部注射曲安奈德预防食管早期癌及癌前病变内镜黏膜下剥离术（endoscopic submucosal dissection,ESD）术后食管狭窄的疗效和安全性。方法回顾性分析2014年12月—2019年2月在东南大学附属中大医院就诊的52例食管早期癌或癌前病变患者的病例资料,其中对照组20例（ESD术后未采取任何预防狭窄的措施）,口服组17例,口服联合局部注射组15例。主要观察：狭窄率、难治性狭窄率、ESD术后内镜下扩张次数、ESD术后首次内镜下扩张距ESD完成的间隔时间;以及是否有手术和糖皮质激素相关不良事件,是否有内镜下扩张的不良反应。结果对照组、口服组和口服联合局部注射组ESD术后狭窄率分别为85.0%（17/20）、47.1%（8/17）和46.7%（7/15）,ESD术后难治性狭窄率分别为75.0%（15/20）、23.5%（4/17）和20.0%（3/15）,内镜下扩张次数分别为3.50（2.25,6.00）次,0.00（0.00,2.50）次和0.00（0.00,2.00）次,ESD术后首次内镜下扩张距ESD完成的间隔时间分别为（27.7±9.4）d、（110.1±46.0）d和（147.4±9.4）d,上述四个指标口服组和口服联合局部注射组均明显低于或少于对照组（P＜0.05）,并且口服组与口服联合局部注射组比较,ESD术后狭窄率、难治性狭窄率和内镜下扩张次数方面差异均无统计学意义（P＞0.05）,但ESD术后首次内镜下扩张距ESD完成的间隔时间方面差异有统计学意义（P＜0.01）。仅对照组有2例发生穿孔,其余患者均未发生ESD、糖皮质激素、内镜下扩张相关的严重不良事件。结论口服泼尼松或者口服泼尼松联合局部注射曲安奈德均可有效且安全地预防食管ESD术后的狭窄,且口服联合局部注射激素可延长ESD术后首次内镜下扩张距ESD完成的间隔时间,有利于患者术后的心理恢复和生活质量的提高。     

内镜黏膜下隧道法剥离术治疗早期食管癌伴黏膜下层纤维化的临床观察

目的评价内镜黏膜下隧道法剥离术（endoscopic submucosal tunnel dissection,ESTD）治疗早期食管癌伴黏膜下层纤维化的效果和安全性。方法2015年6月—2018年2月间,在江苏省苏北人民医院消化内科采用ESTD或内镜黏膜下剥离术（endoscopic submucosal dissection,ESD）治疗,术后病理证实病灶＜1/3食管管周,且伴有黏膜下层纤维化的早期食管癌病例87例纳入回顾性分析,按纤维化程度分成轻度纤维化60例（ESTD 31例、ESD 29例）和重度纤维化27例（ESTD 16例、ESD 11例）,比较同一纤维化程度时两种手术方式的剥离速度、整块切除率、完全切除率,以及出血、肌层损伤、穿孔、颈部皮下气肿和术后狭窄的发生率。结果对于伴有轻度黏膜下层纤维化的早期食管癌患者,ESTD的整块切除率[96.8%（30/31）比82.8%（24/29）,P＜0.05]和完全切除率[96.8%（30/31）比75.9%（22/29）,P＜0.05]明显高于ESD,固有肌层损伤发生率明显低于ESD[6.5%（2/31）比17.2%（5/29）,P＜0.05],剥离速度、术中出血发生率、穿孔发生率、术后狭窄发生率与ESD比较差异均无统计学意义（P均＞0.05）,两种手术方式均无术后迟发性出血和颈部皮下气肿发生。对于伴有重度黏膜下层纤维化的早期食管癌患者,ESTD的剥离速度快于ESD[（12.3±2.8）mm2/min比（7.1±3.2）mm2/min],整块切除率、完全切除率、术后狭窄发生率与ESD相近,术中出血发生率[12.5%（2/16）比54.5%（6/11）]、固有肌层损伤发生率[18.8%（3/16）比54.5%（6/11）]、穿孔发生率[6.3%（1/16）比27.3%（3/11）]、颈部皮下气肿发生率[6.3%（1/16）比27.3%（3/11）]低于ESD,两种手术方式均无术后迟发性出血发生。术后12个月2例行ESD和1例行ESTD患者局部复发,术后24个月1例行ESTD患者发生异时癌。结论ESTD能安全、有效切除伴有黏膜下层纤维化的早期食管癌。对于伴有轻度黏膜下层纤维化者,ESTD的优势主要体现在治疗效果方面;对于伴有重度黏膜下层纤维化者,ESTD的优势主要体现在治疗安全性方面。     

聚乙醇酸网片联合口服激素对巨大早期食管癌内镜黏膜下剥离术后食管狭窄的预防作用

为了评估聚乙醇酸网片（polyglycolic acid sheet,PGA）联合口服激素用于巨大早期食管癌内镜黏膜下剥离术（endoscopic submucosal dissection,ESD）后食管狭窄的预防作用,收集2013年1月至2024年3月间在华中科技大学同济医学院附属同济医院行ESD治疗,术后病理证实为早期食管癌,术后缺损≥3/4食管管周,采用单纯口服激素（单纯口服激素组,n=27）或PGA联合口服激素（PGA联合口服激素组,n=18）预防术后食管狭窄的45例病例纳入回顾性研究,对比分析发现：PGA联合口服激素组术后食管狭窄率明显低于单纯口服激素组［44.4%（8/18）比74.1%（20/27）,χ2=4.034,P=0.043］,且≥3/4管周的非环周型食管缺损病例中,PGA联合口服激素组仅有1例［9.1%（1/11）］发生术后食管狭窄,而单纯口服激素组有10例［62.5%（10/16）］发生术后食管狭窄;在随访过程中,未观察到激素使用的严重并发症,也未观察到与PGA使用相关的不良事件。以上结果初步说明,PGA联合口服激素预防巨大早期食管癌ESD术后食管狭窄安全、有效,且预防效果优于单纯口服激素。     

Q法自牵引技术在大范围早期食管癌内镜 黏膜下剥离术中的应用研究（含视频）

目的初步报告Q法自牵引辅助内镜黏膜下剥离术(Q-ESD)应用于大范围早期食管癌(EEC)的临床效果。方法回顾性分析2015年1月至2018年12月间在福建省立医院接受ESD治疗的82例大范围EEC(单发病灶>1/2周径或纵径长度>5 cm)患者病例资料,按治疗方案不同分为传统ESD组(n=44)和Q-ESD组(n=38),比较两组操作面积、操作时间、操作速度、整块切除率、完整切除率、并发症情况。结果82例病灶均于内镜下成功整块切除。Q-ESD组和传统ESD组在操作面积[779.8(329.9~2552.5)mm^2比875.7(417.8~1914.8)mm^2,U=155,P=0.636]、操作时间[63(41~177)min比59(42~169)min,U=171,P=0.167]、完整切除率[94.7%(36/38)比93.2%(41/44),χ^2=0.086,P=0.769]方面比较差异无统计学意义。但Q-ESD组操作速度快[14.9(5.4~20.8)mm^2/min比9.0(5.0~19.5)mm^2/min,U=142,P=0.035],固有肌层损伤发生率低[7.9%(3/38)比27.3%(12/44),χ^2=5.123,P=0.023],术后狭窄发生率低[5.3%(2/38)比20.5%(9/44),χ^2=4.051,P=0.044]。除传统ESD组有1例穿孔外,未发生其他不良事件。结论Q-ESD是治疗大范围EEC安全有效的可选策略。     

Feasibility of same-day discharge following endoscopic submucosal dissection for esophageal or gastric early cancer

BACKGROUNDEndoscopic submucosal dissection (ESD) is an established technique for the treatment of early gastrointestinal neoplasia. Generally, multi-day (M-D) admission is required for patients undergoing ESD due to potential complications.AIMTo evaluate the feasibility of a same-day (S-D) discharge strategy for ESD of the esophagus or stomach.METHODSThe data of patients who underwent esophageal or gastric ESD were retrospectively collected from January 2018 to December 2021 at Peking University Cancer Hospital. The propensity score matching (PSM) method was applied to balance the unevenly distributed patient baseline characteristics between the S-D and M-D groups. Intraoperative and postoperative parameters were compared between the matched groups.RESULTSAmong the 479 patients reviewed, 470 patients, including 91 in the S-D group and 379 in the M-D group, fulfilled the inclusion and exclusion criteria. Following PSM, 78 patients in each group were paired using the 1:1 nearest available score match algorithm. No significant difference was found between groups with respect to intraoperative and postprocedural major adverse events (AEs). Tumor size, complete resection rate, and procedural duration were comparable between the groups. The S-D group demonstrated a significantly shorter length of hospital stay (P < 0.001) and lower overall medical expenses (P < 0.001) compared with the M-D group.CONCLUSIONThe S-D discharge strategy may be feasible and effective for esophagogastric ESD, and the procedural-related AEs can be managed successfully.     

Predictive factors for esophageal stenosis after endoscopic submucosal dissection for superficial esophageal cancer

Endoscopic submucosal dissection (ESD) has been utilized as an alternative treatment to endoscopic mucosal resection for superficial esophageal cancer. We aimed to evaluate the complications associated with esophageal ESD and elucidate predictive factors for post‐ESD stenosis. The study enrolled a total of 42 lesions of superficial esophageal cancer in 33 consecutive patients who underwent ESD in our department. We retrospectively reviewed ESD‐associated complications and comparatively analyzed regional and technical factors between cases with and without post‐ESD stenosis. The regional factors included location, endoscopic appearance, longitudinal and circumferential tumor sizes, depth of invasion, and lymphatic and vessel invasion. The technical factors included longitudinal and circumferential sizes of mucosal defects, muscle disclosure and cleavage, perforation, and en bloc resection. Esophageal stenosis was defined when a standard endoscope (9.8 mm in diameter) failed to pass through the stenosis. The results showed no cases of delayed bleeding, three cases of insidious perforation (7.1%), two cases of endoscopically confirmed perforation followed by mediastinitis (4.8%), and seven cases of esophageal stenosis (16.7%). Monovalent analysis indicated that the longitudinal and circumferential sizes of the tumor and mucosal defect were significant predictive factors for post‐ESD stenosis (P < 0.005). Receiver operating characteristic analysis showed the highest sensitivity and specificity for a circumferential mucosal defect size of more than 71% (100 and 97.1%, respectively), followed by a circumferential tumor size of more than 59% (85.7 and 97.1%, respectively). It is of note that the success rate of en bloc resection was 95.2%, and balloon dilatation was effective for clinical symptoms in all seven patients with post‐ESD stenosis. In conclusion, the most frequent complication with ESD was esophageal stenosis, for which the sizes of the tumor and mucosal defect were significant predictive factors. Although ESD enables large en bloc resection of esophageal cancer, practically, in cases with a lesion more than half of the circumference, great care must be taken because of the high risk of post‐ESD stenosis.     

体外自助式扩张球囊预防食管大面积病变内镜黏膜下剥离术后狭窄的长期疗效分析

目的 评估体外自助式扩张球囊预防食管大面积病变内镜黏膜下剥离术（endoscopic submucosal dissection,ESD）后食管狭窄的长期有效性和安全性。方法 前瞻性纳入2018年1月—2019年12月在解放军总医院第一医学中心行ESD且术后黏膜缺损≥5/6食管环周、长度30～100 mm的早期食管癌或癌前病变患者,术后使用体外自助式扩张球囊预防食管狭窄。ESD术后食管黏膜缺损分为2级:1级为≥5/6环周但未累及全环周;2级累及全环周。观察术后狭窄发生率,狭窄出现时间,内镜下球囊扩张（endoscopic balloon dilations,EBD）或放射状切开（radial incision and cuttings,RIC）治疗狭窄的次数,以及其他不良事件发生率。结果 共27例患者纳入研究,随访14～38个月,其中术后黏膜缺损范围1级的患者3例,2级24例。术后黏膜缺损长度（73.7±18.4）mm,球囊放置时间（92.0±20.0）d;总狭窄发生率为18.5%（5/27）,其中术后黏膜缺损2级的患者狭窄发生率为16.7%（4/24）。球囊取出到发生狭窄的中位时间为17 d,其中2例狭窄患者分别进行了3次EBD治疗,其余3例患者分别接受了2次、1次和2次RIC治疗。所有患者在佩戴球囊过程中未出现穿孔和迟发性出血。结论 对于ESD术后黏膜缺损≥5/6食管环周且长度≤100 mm的食管大面积病变患者,体外自助式扩张球囊是一种安全有效的预防术后狭窄的方法。     

Endoscopic submucosal tunnel dissection salvage technique for ulcerative early gastric cancer

Endoscopic submucosal dissection is an effective treatment modality for early gastric cancer (EGC), though the submucosal fibrosis found in ulcerative EGC is an obstacle for successful treatment. This report presents two cases of ulcerative EGC in two males, 73- and 80-year-old, with severe fibrosis. As endoscopic ultrasonography suggested that the EGCs had invaded the submucosal layer, the endoscopic submucosal tunnel dissection salvage technique was utilized for complete resection of the lesions. Although surgical gastrectomy was originally scheduled, the two patients had severe coronary heart disease, and surgeries were refused because of the risks associated with their heart conditions. The endoscopic submucosal tunnel dissection salvage technique procedures described in these cases were performed under conscious sedation, and were completed within 30 min. The complete en bloc resection of EGC using endoscopic submucosal tunnel dissection salvage technique was possible with a free resection margin, and no other complications were noted during the procedure. This is the first known report concerning the use of the endoscopic submucosal tunnel dissection salvage technique salvage technique for treatment of ulcerative EGC. We demonstrate that endoscopic submucosal tunnel dissection salvage technique it is a feasible method showing several advantages over endoscopic submucosal dissection for cases of EGC with fibrosis.     

Useful strategies to prevent severe stricture after endoscopic submucosal dissection for superficial esophageal neoplasm

The minimal invasiveness of endoscopic submucosal dissection (ESD) prompted us to apply this technique to large-size early esophageal squamous cell carcinoma and Barrett’s adenocarcinoma, despite the limitations in the study population and surveillance duration. A post-ESD ulceration of greater than three-fourths of esophageal circumference was advocated as an important risk factor for refractory strictures that require several sessions of dilation therapy. Most of the preoperative conditions are asymptomatic, but dilatation treatment for dysphagia associated with the stricture has potential risks of severe complications and a worsening of quality of life. Possible mechanisms of dysphasia were demonstrated based on dysmotility and pathological abnormalities at the site: (1) delayed mucosal healing; (2) severe inflammation and disorganized fibrosis with abundant extracellular matrices in the submucosa; and (3) atrophy in the muscularis proper. However, reports on the administration of anti-scarring agents, preventive dilation therapies, and regenerative medicine demonstrated limited success in stricture prevention, and there were discrepancies in the study designs and protocols of these reports. The development and consequent long-term assessments of new prophylactic technologies on the promotion of wound healing and control of the inflammatory/tumor microenvironment will require collaboration among various research fields because of the limited accuracy of preoperative staging and high-risk of local recurrence.     

Efficacy and safety of endoscopic submucosal tunnel dissection for superficial esophageal squamous cell carcinoma and precancerous lesions

AIM To evaluate the clinical outcomes of patients who underwent endoscopic submucosal tunnel dissection(ESTD) for esophageal squamous cell carcinoma(ESCC) and precancerous lesions.METHODS ESTD was performed in 289 patients. The clinical outcomes of the patients and pathological features of the lesions were retrospectively reviewed.RESULTS A total of 311 lesions were included in the analysis. The en bloc rate, complete resection rate, and curative resection rate were 99.04%, 81.28%, and 78.46%, respectively. The ESTD procedure time was 102.4 ± 35.1 min, the mean hospitalization time was 10.3 ± 2.8 d, and the average expenditure was 3766.5 ± 846.5 dollars. The intraoperative bleeding rate was 6.43%, the postoperative bleeding rate was 1.61%, the perforation rate was 1.93%, and the postoperative infection rate was 9.65%. Esophageal stricture and positive margin were severe adverse events, with an incidence rate of 14.79% and 15.76%, respectively. No tumor recurrence occurred during the follow-up period. CONCLUSION ESTD for ESCC and precancerous lesions is feasible and relatively safe, but for large mucosal lesions, the rate of esophageal stricture and positive margin is high.