ENDOSCOPIC SUBMUCOSAL DISSECTION FOR THE RELIABLE EN BLOC RESECTION OF COLORECTAL MUCOSAL TUMORS

Scheduled piecemeal resection has been actively conducted for granular type laterally spreading tumor (LST‐G) in Japan, as long as a definite preoperative diagnosis is made. However, en bloc resection is desirable for depressed lesions (e.g. IIc lesion) as well as non‐granular type laterally spreading tumor (LST‐NG) since they have considerable high risk for submucoasl invasion and require precise histopathological evaluation. Endoscopic submucosal dissection (ESD) has been developed for the en bloc resection of mucosal tumors of gastrointestinal tract and widely applied especially in gastric lesions. Although the large intestine involves structural and technical difficulties, we conducted en bloc resection by ESD while exercising sorts of ingenuity for preparation; endoscopes, instruments, local injections, and others. ESD is a reliable technique that allows en bloc resection of gastrointestinal mucosal lesions, and even has a splendid possibility for the treatment of early stage colorectal cancer.     

Clinical outcomes of endoscopic submucosal dissection and endoscopic mucosal resection for laterally spreading tumors larger than 20 mm

Background and Aims: Colorectal laterally spreading tumors (LST) > 20 mm are usually treated by endoscopic submucosal dissection (ESD) or endoscopic mucosal resection (EMR). Endoscopic piecemeal mucosal resection (EPMR) is sometimes required. The aim of our study was to compare the outcomes of ESD and EMR, including EPMR, for such LST. Methods: A total of 269 consecutive patients with a colorectal LST > 20 mm were treated endoscopically at our hospital from April 2006 to December 2009. We retrospectively evaluated the complications and local recurrence rates associated with ESD, hybrid ESD (ESD with EMR), EMR, and EPMR. Results: ESD and EMR were performed successfully for 89 and 178 LST, respectively: 61 by ESD; 28 by hybrid ESD; 70 by EMR; and 108 by EPMR. Between‐group differences in perforation rates were not significant. Local recurrence rates in cases with curative resection were as follows: 0% (0/56) in ESD; 0% (0/27) in hybrid ESD; 1.4% (1/69) in EMR; and 12.1% (13/107) in EPMR; that is, significantly higher in EPMR. No metastasis was seen at follow up. The recurrence rate for EPMR yielding ≥ three pieces was significantly high (P < 0.001). All 14 local recurrent lesions were adenomas that were cured endoscopically. Conclusions: As for safety, ESD/hybrid ESD is equivalent to EMR/EPMR. ESD/hybrid ESD is a feasible technique for en bloc resection and showed no local recurrence. Although local recurrences associated with EMR/EPMR were seen, which were conducted based on our indication criteria, all local recurrences could obtain complete cure by additional endoscopic treatment.     

Colorectal endoscopic submucosal dissection: present status and future perspective,including its differentiation from endoscopic mucosal resection

Endoscopic submucosal dissection (ESD) allows en bloc resection of a lesion, irrespective of the size of the lesion. ESD has been established as a standard method for the endoscopic ablation of malignant tumors in the upper gastrointestinal (GI) tract in Japan. Although the use of ESD for colorectal lesions has been studied via clinical research, ESD is not yet established as a standard therapeutic method for colorectal lesions because colorectal carcinoma has unique pathological, organ specific characteristics that differ radically from those of the esophagus and stomach, and scope handling and control is more difficult in the colorectum than in the upper GI tract. Depending on the efficacy of endoscopic mucosal resection (EMR) and the clinicopathological characteristics of the colorectal tumor, the proposed indications for colorectal ESD are as follows: (1) lesions difficult to remove en bloc with a snare EMR, such as nongranular laterally spreading tumors (particularly the pseudo depressed type), lesions showing a type VI: pit pattern, and large lesions of the protruded type suspected to be carcinoma; (2) lesions with fibrosis due to biopsy or peristasis; (3) sporadic localized lesions in chronic inflammation such as ulcerative colitis; and (4) local residual carcinoma after EMR. Colorectal ESD is currently in the development stage, and a standard protocol will be available in the near future. We hope that colorectal tumors will be efficiently treated by a treatment method appropriately selected from among EMR, ESD, and surgical resection after precise preoperative diagnosis based on techniques such as magnifying colonoscopy.     

RISK MANAGEMENT OF THERAPEUTIC COLONOSCOPY (HOT BIOPSY,POLYPECTOMY, ENDOSCOPIC MUCOSAL RESECTION AND ENDOSCOPIC SUBMUCOSAL DISSECTION)

The concept of an adenoma–carcinoma sequence has been widely accepted in the colon and rectum, contrary to that in gastric cancer. Consequently, most target lesions for endoscopic resection using these newly developed techniques are histologically assessed as adenoma or intramucosal carcinoma in adenoma. Based on results in conventional endoscopic mucosal resection (EMR), almost all remnant or recurrent tumors can be successfully managed by salvage EMR, and all materials resected by salvage EMR also showed adenoma or intramucosal cancer. These results suggest that en bloc resection is not always clinically necessary to obtain complete cure for all colorectal neoplasia. However, larger lesions tend to be resected in a piecemeal fashion; it is difficult to confirm whether EMR has been completed or not. For precise histopathological assessment of the resected specimen, endoscopic submucosal dissection (ESD) for en bloc resection is desirable, although further experience is needed to establish its safety and efficacy. The present review contains a summary of the risk management of therapeutic colonoscopy including ESD for large colorectal mucosal neoplasia, debated at the Endoscopic Forum Japan 2006, Hakone, and discussion of the problems and future prospects of these procedures.     

ENDOSCOPIC SUBMUCOSAL DISSECTION FOR RECURRENT GASTRIC TUMORS

Endoscopic resection has been accepted as the standard treatment for intramucosal gastric tumors of differentiated type. However, the indication was limited to small tumors to achieve en bloc resection and prevent local recurrence in cases of conventional endoscopic mucosal resection (EMR) such as the strip biopsy and the cap technique. To avoid multi‐fragmental resection, we have developed endoscopic submucosal dissection (ESD) as a new endoscopic resection technique. ESD is a remarkable technique, because we make it possible to remove the lesions en bloc regardless of size, shape, coexisting ulcer, and location. However, it is difficult or impossible to resect recurrent tumors en bloc in conventional EMR owing to hard fibrosis, and some patients need laparotomy. Using ESD, we can dissect the submucosal layer as we directly look at the submucosa, and remove the lesion safely and reliably even in cases of hard fibrosis. The key to treatment of recurrent tumors in ESD are as follows: (i) using enough submucosal injection solution (we use a mixture of Glyceol and 1% 1900 kDa hyaluronic acid preparation); (ii) incising the mucosa without fibrosis; (iii) understanding characteristics of various cutting devices, and changing other devices in difficult situations. In these ways we can remove the majority of the recurrent tumors en bloc. Hence, we consider that ESD is a very effective treatment which achieves excellent en bloc and complete resection rates and enables patients with intramucosal gastric tumors to a recurrent‐free survival even in recurrent tumors.     

CURRENT TECHNIQUES AND DEVICES FOR SAFE AND CONVENIENT ENDOSCOPIC SUBMUCOSAL DISSECTION (ESD) AND KOREAN EXPERIENCE OF ESD

Conventional endoscopic mucosal resection (EMR) technique has limitations in its capacity of achieving en bloc resection and, for lesions greater than 20 mm, removal in a piecemeal resection is often required. This leads to uncertainty as to whether or not the lesion has been completely removed and to an increase in local recurrence. To overcome this limitation, a new technique using specifically designed cutting devices, termed endoscopic submucosal dissection (ESD) has been developed. The present article discuss the current indication, new diagnostic, cutting and hemostatic devices and long‐term outcomes of EMR and ESD in early gastric cancer in Korea.     

Impact of endoscopic submucosal dissection for the therapeutic strategy of large colorectal tumors

Background and Aims: The change of therapeutic strategy for large colorectal tumors after the introduction of endoscopic submucosal dissection (ESD) has not yet been clarified. The aim of this study was to estimate the impact of ESD as an initial treatment strategy. Methods: A questionnaire was administered to nine expert panelists in colorectal ESD. The questionnaire used retrospective data from consecutive case series. Forty‐seven cases of early colorectal tumors (≥ 20 mm) were included. Endoscopic growth types were 25 laterally‐spreading tumors (LST) of granular type (G), 15 LST of non‐granular types (NG), and seven protruded types. Pathological diagnoses included 15 adenomas (Ad), 18 intramucosal cancers (M), three submucosally‐shallow invasive cancers (< 1000 µm) (SMs), and 11 submucosally‐deep invasive cancers (≥ 1000 µm) (SMd). The expert panelists completed questionnaires about recommended initial treatment under suppositions of before and after the introduction of ESD. Over‐surgery was defined as surgery for Ad, M, and SMs. Non‐curative endoscopic resection (ER) was defined as ER for SMd. Results: After the introduction of ESD, the reduction in the over‐surgery rate was estimated at 10.8% for Ad, M, and SMs, and the increase in the non‐curative ER rate was estimated at 27.2% for SMd. By endoscopic growth type, the reduction of over‐surgery rates for LST–NG, LST–G, and protruded type was 15.5%, 10.5%, and 2.2%, respectively. Conclusions: The endoscopists changed their therapeutic strategy for large colorectal tumors to reduce over‐surgery, especially in LST–NG, demonstrating the impact of ESD.     

Risk factors for incomplete resection and complications in endoscopic mucosal resection for lateral spreading tumors

Aim: Lateral spreading tumors (LST) are relatively large flat lesions with diameters exceeding 10 mm in length. Endoscopic mucosal resection (EMR) is a commonly used technique for removing LST. We aimed to evaluate the risk factors for incomplete resection and complications of EMR for LST. Method: Between January 2004 and December 2010, 497 patients who underwent EMR for LST were retrospectively reviewed. Risk factors for endoscopic and histopathological complete resection, complications, and clinical outcomes were investigated. Results: Risks for incomplete resection by piecemeal resection and en bloc resection of a lesion ≥30 mm were higher than for en bloc resection of a lesion <30 mm (OR = 2.688, CI 1.036–6.993; OR = 4.982, CI 1.894–13.101). Risks of post‐EMR bleeding for piecemeal resection and en bloc resection for a lesion ≥40 mm were higher than for en bloc resection of a lesion < 40 mm (OR = 15.231, CI 1.816–127.744; OR = 43.043, CI 4.306–430.314). Conclusion: We found risk factors of EMR for LST and tentatively suggest a protocol for EMR adapted to the size of LST and resection methods. (i) Following piecemeal resection and en bloc resection for LST ≥ 40 mm, hospitalize patients for 36 h and note risk for incomplete resection and delayed bleeding. (ii) After en bloc resection for 40 mm > LST ≥ 30 mm, hospitalize patients for 12 h and note risk for incomplete resection. (iii) Following en bloc resection for LST < 30 mm, hospitalize the patient for 12 h and expect complete resection.     

Endoscopic mucosal resection with a ligation device or endoscopic submucosal dissection for rectal carcinoid tumors: An analysis of 24 consecutive cases

Aims: Endoscopic submucosal dissection (ESD) has several advantages over conventional endoscopic mucosal resection, including a higher en bloc resection rate and more accurate pathological estimation. However, ESD is a complex procedure that requires advanced endoscopic skills. The aim of our study is to evaluate the efficacy of endoscopic mucosal resection with a ligation device (EMR‐L) compared to ESD for rectal carcinoid tumors. Methods: Between September 2003 and April 2011, 24 rectal carcinoid tumors in 24 patients treated by ESD or EMR‐L were retrospectively analyzed. The indications for endoscopic treatment were node‐negative rectal carcinoid tumors. We compared the therapeutic outcomes of the ESD group (n = 13) and the EMR‐L group (n = 11). Results: Both groups had similar mean tumor sizes (ESD: 5.5 ± 2.1 mm; EMR‐L: 4.4 ± 2.2 mm). The rates of en bloc and complete resection were, respectively, 100% and 92.3% for ESD, and 100% and 100% for EMR‐L. Perforations did not occur in either group. Postoperative bleeding occurred in one EMR‐L case, and it was endoscopically managed. However, there were no differences in therapeutic outcomes between the two groups. The mean procedure time was longer in the ESD group (28.8 ± 16.2 min) than in the EMR‐L group (17.4 ± 4.4 min), without a significant difference. The mean hospitalization period was significantly shorter in the EMR‐L group (1.8 ± 3.1 day) than in the ESD group (6.2 ± 2.1 day), and eight EMR‐L cases were treated in an outpatient setting. Conclusions: EMR‐L is a simple and effective procedure that compares favorably to ESD for small rectal carcinoid tumors.     

TECHNIQUES AND PITFALLS OF ENDOSCOPIC SUBMUCOSAL DISSECTION FOR COLORECTAL TUMORS

Endoscopic submucosal dissection (ESD) for colorectal tumors is steadily being developed. Safety and standardization of ESD for colorectal tumors have not been yet established because of the technical difficulties and the unsuitable anatomical characteristics of the colon and rectum. The authors mainly use a Flex knife for mucosal incision and a Hook knife for submucosal dissection to perform ESD safely. Skillful colonoscopic control, selection of scope, distal attachment tip hood, adequate high‐frequency generator and correct approach strategy should all be considered for safe performance of ESD. However, the incidence of indicative lesions is rare because the majority of colorectal tumors are adenomatous large laterally spreading tumors, which can be cured by intentional endoscopic piecemeal resection. At present, ESD for colorectal tumors should be performed only at central facilities that have expert colonoscopists. With the development of new devices and associated techniques, technical standardization of ESD for colorectal tumors is expected in the near future.     

Matched case-control study comparing endoscopic submucosal dissection and endoscopic mucosal resection for colorectal tumors

Background and Aim: For large colorectal tumors, the en bloc resection rate achieved by endoscopic mucosal resection (EMR) is insufficient, and this leads to a high rate of local recurrence. As endoscopic submucosal dissection (ESD) has been reported to achieve a higher rate of en bloc resection and a lower rate of local recurrence in the short‐term, it is expected to overcome the limitations of EMR. We conducted a matched case‐control study between ESD and EMR to clarify the effectiveness of ESD for colorectal tumors. Methods: Between April 2005 and February 2009, a total of 28 colorectal tumors in 28 patients were resected by ESD and were followed up by colonoscopy at least once. As a control group, 56 EMR cases from our prospectively completed database were matched. En bloc resection, complication and recurrence rates were compared between the two groups. Results: The mean sizes of the lesions were 27.1 mm in the ESD group and 25.0 mm in the EMR group. The en bloc resection rate was significantly higher in the ESD group (92.9% vs 37.5% with ESD vs EMR), and the rate of perforation was also significantly higher (10.7% vs 0%). All cases of perforation were managed conservatively. No recurrence was observed in the ESD group, whereas local recurrences were detected in 12 EMR cases (21.4%). Eleven of the 12 recurrences (91.7%) were managed endoscopically, and one required surgical resection. Conclusions: Endoscopic submucosal dissection is a promising technique for the treatment of colorectal tumors, giving an excellent outcome in comparison with EMR.     

Beyond the snare: technically accessible large en bloc colonic resection in the West: an animal study

Background: Endoscopic submucosal dissection (ESD) and circumferential submucosal incision endoscopic mucosal resection (CSI‐EMR) are techniques for en bloc excision of large sessile colonic lesions. Our aims were to compare the efficacy, safety and learning curve of colonic hybrid knife (HK) ESD versus CSI‐EMR for en bloc excision of 50 mm diameter hemi‐circumferential artificial lesions in a porcine model. Patients and Methods: Two separate 50 mm diameter areas of normal recto‐sigmoid mucosa were marked out in each of ten pigs. One was excised with HK‐ESD using succinylated gelatin (SG) submucosal injection. The other was isolated with CSI with the Insulated Tip Knife 2 followed by SG submucosal injection then EMR with a large snare. Euthanasia and colectomy was performed at 72 h followed by blinded histopathology assessment. Results: En bloc excision rates were: HK‐ESD 100% versus CSI‐EMR 20% (P = 0.008). The mean number of resections per lesion was HK‐ESD 1 versus CSI‐EMR 3 (P = 0.001). The mean dimensions of the largest specimen per technique were HK‐ESD 63 × 54 mm versus CSI‐EMR 49 × 41 mm (P = 0.005). Procedure duration mean was HK‐ESD 54 min versus CSI‐EMR 22 min (P < 0.001). When procedure duration was adjusted for the size of the resected en bloc specimen, a statistically significant and accelerated learning effect was noted for HK‐ESD (r = ?0.83, P = 0.003). There were no perforations and no significant bleeding. Conclusions: HK‐ESD with SG submucosal injection is superior to CSI‐EMR for en bloc excision of 50 mm diameter lesions in a porcine model. The technique is rapidly learnt. This novel approach may lower the barrier to colonic ESD for Western endoscopists.     

Indications for and Technical Aspects of Colorectal Endoscopic Submucosal Dissection

Due to the widespread acceptance of gastric and esophageal endoscopic submucosal dissections (ESDs), the number of medical facilities that perform colorectal ESDs has grown and the effectiveness of colorectal ESD has been increasingly reported in recent years. The clinical indications for colorectal ESD at the National Cancer Center Hospital, Tokyo, Japan include laterally spreading tumor (LST) nongranular type lesions >20 mm and LST granular type lesions >30 mm. In addition, 0-IIc lesions >20 mm, intramucosal tumors with nonlifting signs and large sessile lesions, all of which are difficult to resect en bloc by conventional endoscopic mucosal resection (EMR), represent potential candidates for colorectal ESD. Rectal carcinoid tumors less than 1 cm in diameter can be treated simply, safely, and effectively by endoscopic submucosal resection using a ligation device and are therefore not indications for ESD. The en bloc resection rate was 90%, and the curative resection rate was 87% for 806 ESDs. The median procedure time was 60 minutes, and the mean size for resected specimens was 40 mm (range, 15 to 150 mm). Perforations occurred in 23 (2.8%) cases, and postoperative bleeding occurred in 15 (1.9%) cases, but only two perforation cases required emergency surgery (0.25%). ESD was an effective procedure for treating colorectal tumors that are difficult to resect en bloc by conventional EMR. ESD resulted in a higher en bloc resection rate as well as decreased invasiveness in comparison to surgery. Based on the excellent clinical results of colorectal ESDs in Japan, the Japanese healthcare insurance system has approved colorectal ESD for coverage.     

Treatment strategy for laterally spreading tumors in Japan: Before and after the introduction of endoscopic submucosal dissection

Background and Aims:  Laterally spreading tumors (LST) in the colorectum are considered good candidates for endoscopic resection (ER). Because LST-non-granular (NG) tumors show multifocal invasion into the submucosal layer, en bloc resection is necessary for adequate histopathological evaluation. Therefore, surgical resection has been recommended when a lesion is suspected to be an invasive cancer and too large to resect en bloc. The aim of the present study was to evaluate whether the introduction of colorectal ESD, which was developed for en bloc resection of early gastric cancers, could improve the en bloc resection rate of large LST-NG-type tumors and reduce the surgical resection rate.
Methods:  Between January 1999 and December 2005, a total of 166 LST-NG-type tumors measuring ≥ 20 mm in 161 patients were included in this study. The en bloc resection rate and the surgical resection rate were historically compared between two periods, before and after the introduction of ESD.
Results:  The en bloc resection rate for ER lesions was significantly higher in the latter period (35.0% [14/40] vs 76.5% [75/98]; P  < 0.001), and the rate of surgery for adenomas and intramucosal or sm minute cancers was significantly lower in the latter period (20.0% [10/50] vs 1.1% [1/89]; P  < 0.001).
Conclusions:  The introduction of colonic ESD was able to change our treatment strategy for LST, improving the en bloc resection rate and reducing the surgical resection rate.     

Endoscopic submucosal dissection of early gastric cancer

The purpose of this review was to examine a remarkable technical advance regarding the indications for and the technique of endoscopic resection of early gastric cancer. Endoscopic mucosal resection (EMR) of early gastric cancer with no risk of lymph node metastasis has been a standard technique in Japan, probably owing to the high incidence of gastric cancer in Japan and the fact that more than half of Japanese gastric cancer cases are diagnosed at an early stage. Very recently, several EMR techniques have become increasingly accepted and regularly used in Western countries. Although these minimally invasive techniques are safe, convenient, and efficacious, they are unsuitable for large lesions in particular. Difficulty in correctly assessing the depth of tumor invasion and an increase in local recurrence when standard EMR procedures are used have been reported in cases of large lesions, because such lesions are often resected piecemeal owing to the technical limitations of standard EMR. A new development in therapeutic endoscopy, called endoscopic submucosal dissection (ESD), allows the direct dissection of the submucosa, and large lesions can be resected en bloc. ESD is not limited by resection size and is expected to replace surgical resection. However, it is still associated with a higher incidence of complications than standard EMR procedures and requires a high level of endoscopic skill. The endoscopic indications, techniques, and management of complications of ESD for early gastric cancer for properly carrying out established therapeutic endoscopy are described.     

Endoscopic submucosal dissection allows curative resection of locally recurrent early gastric cancer after prior endoscopic mucosal resection

BACKGROUND: Repeat endoscopic mucosal resection (EMR) to cure locally recurrent early gastric cancer (EGC) is difficult to perform because the initial EMR causes submucosal fibrosis; however, ESD allows submucosal dissection through the fibrosis and provides an en bloc specimen. OBJECTIVE: The objective was to determine the safety and efficacy of ESD and compare the results to historical controls. DESIGN: This was a retrospective, case-control study. PATIENTS: We used our prospectively entered database (1993-2003) to identify 64 patients who had locally recurrent EGC after EMR. MAIN OUTCOME MEASUREMENTS: We defined the resections as curative when the lateral and vertical margins were free of cancer and repeat endoscopy showed no recurrent disease. RESULTS: Among 46 patients who underwent ESD, 41 (89.1%) en bloc resections were achieved compared to none in 18 conventional procedures (P < .0001). The specimen of 1 lesion (2.4%) out of 41 en bloc resections was histologically nonevaluable, compared with 10 lesions (43.4%) in 23 piecemeal resections (P < .0001). Three residual tumors (27.3%) were found in the 11 nonevaluable specimens. Three perforations occurred during ESD; all were successfully treated endoscopically with endoclips. LIMITATIONS: The limitation of the study was retrospective design. CONCLUSIONS: ESD provides high en bloc resection rate for locally recurrent EGC after previous EMR. In turn, en bloc resections allow precise histological staging to be assessed and prevent residual disease and recurrence.     

大肠侧向发育型肿瘤内镜下的诊断与治疗

目的探讨大肠侧向发育型肿瘤（LST）临床病理特征及内镜下黏膜切除术的有效性、安全性。方法经普通内镜检查发现LST 119例,染色后观察病灶大小及部位并进行形态分型,再结合放大内镜确定腺管开口类型。有治疗适应证者行内镜下黏膜切除术,切除病灶黏膜送病理检查。结果 28个月中共发现119例LST 124个病变。内镜下分型：颗粒均一型44个,结节混合型48个,平坦隆起型23个,假凹陷型9个。病变直径：10～20 mm 65个,21～30 mm 23个,31 mm以上36个,最大病变110 mm×100 mm。病变部位：直肠50个,乙状结肠25个,降结肠11个,横结肠10个,升结肠＋盲肠28个。黏膜腺管开口类型：Ⅲ型30个,其中17个为管状绒毛状腺瘤,12个为管状腺瘤;Ⅳ型56个,其中30个为绒毛状腺瘤,4个为黏膜内癌;Ⅴ型5个,其中2个为黏膜内癌,2个累及黏膜下层下1/3以下;Ⅱ型7个,其中5个为炎性增生性息肉,2个为锯齿状腺瘤（腺瘤性增生性息肉）：其余为ⅢL＋V型,其中23个为管状绒毛状腺瘤。符合适应证95例98个病变择期进行内镜下黏膜切除治疗,发生出血11例,均在操作过程中,无肠穿孔发生。结论大肠LST内镜形态具有一定特殊性,内镜下黏膜切除术是治疗在大肠的有效而安全的方法,可达到根治目的 。     

内镜智能分光比色技术定位下EMR及ESD治疗大肠侧向发育型肿瘤的疗效比较

[目的]比较内镜智能分光比色技术(FICE)定位下内镜下黏膜切除术(endoscopic mucosal resection,EMR)及内镜黏膜下剥离术(endoscopic submucasal dissection,ESD)治疗大肠侧向发育型肿瘤(LST)的效果。[方法]63例LST患者在FICE定位下分别行EMR(38例)及ESD(25例)治疗,对比分析EMR和ESD两种方法的切除效果、手术时间及并发症。[结果]对于最大径≤20mm的肿瘤,EMR和ESD两种方法均能整块切除,且无肿瘤残留(P0.05);对于最大径20mm的肿瘤,ESD能整块切除,EMR需分次切除(P0.05),且ESD术后肿瘤残留明显少于EMR(P0.05)。ESD手术时间明显长于EMR(P0.05),但术后出血率和穿孔率,两者比较差异无统计学意义(P0.05)。[结论]ESD治疗LST安全有效,而EMR操作简便,用时较短,对于≤20mm的LST仍然是一种较好的选择。     

结直肠侧向发育型肿瘤内镜诊断与治疗

目的探讨结直肠侧向发育型肿瘤(LST)内镜诊断方法,经内镜黏膜切除术(EMR)、分片切除术(EPMR)、内镜黏膜下剥离术(ESD)方法治疗LST的疗效、安全性。方法 LST经色素染色放大内镜或NBI-ME观察病变形态、腺管开口分型(pit)及表面微血管分型(MP),分别进行EMR、EPMR、ESD或外科手术治疗,并分析LST的病理特点。结果在399例病人检出有LST,共407个病变。LST大小在10～80mm。LST部位在直肠128个(31.4%),乙状结肠97个(23.8%),降结肠54个(13.3%),横结肠67个(16.5%),升结肠21个(5.2%),盲肠36个(8.8%),回肠末段4例(1.0%)。LST形态呈颗粒均一型145个,结节混合型161个,扁平隆起型63个,假凹陷型38个。LST腺管开口分型以ⅢL和Ⅳ为多。405个LST经肠镜微创电切治疗,228个行EMR切除,165个行EPMR切除,12个行ESD切除,均在内镜下成功电切,另2例LST行外科手术治疗。出血发生率4.0%,术中即刻出血4例,术后3天迟发出血12例,无肠穿孔发生。LST病理结果:管状腺瘤46个(11.3%),管状绒毛状腺瘤146个(35.9%),绒毛状腺瘤181个(44.5%),增生性息肉10个(2.5%),高级别上皮内瘤变19个(4.7%),黏膜内癌3个(0.7%),黏膜下癌2个(0.4%)。术后复查肠镜无复发。结论色素染色放大内镜或NBI-ME方法有利于检出LST,EMR、EPMR、ESD是内镜下治疗LST安全有效的方法。     

ENDOSCOPIC MUCOSAL RESECTION AND SUBMUCOSAL DISSECTION METHOD FOR LARGE COLORECTAL TUMORS

The goal of endoscopic mucosal resection (EMR) is to allow the endoscopist to obtain tissue or resect lesions not previously amenable to standard biopsy or excisional techniques and to remove malignant lesions without open surgery. In this article, we describe the results of conventional EMR and EMR using an insulation‐tipped (IT) electrosurgical knife (submucosal dissection method) for large colorectal mucosal neoplasms and discuss the problems and future prospects of these procedures. At present, conventional EMR is much more feasible than EMR using IT‐knife from the perspectives of time, money, complication, and organ preservation. However, larger lesions tend to be resected in a piecemeal fashion; and it is difficult to confirm whether EMR has been complete. For accurate histopathological assessment of the resected specimen en bloc EMR is desirable although further experience is needed to establish its safety and efficacy. Further improvements of in EMR with special knife techniques are required to simply and safely remove large colorectal neoplasms.