Recently, an increase in well-differentiated rectal neuroendocrine tumors (WRNETs) has been noted. We aimed to evaluate transanal endoscopic microsurgery (TEM) for the treatment of WRNETs.
Between December 1995 and August 2009, 109 patients with WRNETs underwent TEM. TEM was performed for patients with tumors sizes of up to 20 mm and without a lymphadenopathy. These patients had been referred from other clinics after having been diagnosed with WRNETs by using a colonoscopic biopsy; they had undergone a failed endoscopic submucosal dissection (ESD) or endoscopic mucosal resection (EMR) and exhibited an involved resection margin and remaining tumor after ESD or EMR, regardless of the distance from the anal verge. This study included 38 patients that had more than three years of follow-up.
The mean age of the patients was 51.3 ± 11.9 years, the mean tumor size was 8.0 ± 3.9 mm, and no morbidity occurred. Thirty-five patients were asymptomatic. TEM was performed after a colonoscopic resection in 13 cases because of a positive resection margin, a residual tumor or a non-lifting lesion. Complete resections were performed in 37 patients; one patient with a positive margin was considered surgically complete. In one patient, liver metastasis and a recurrent mesorectal node occurred after five and 10 years, respectively.
TEM might provide an accessible and effective treatment either as an initial or as an adjunct after a colonoscopic resection for a WRNET.
Well-differentiated rectal neuroendocrine tumors; Transanal endoscopic microsurgery; Colonoscopic resection; Treatment
The incidence of rectal carcinoids is rising because of the widespread use of screening colonoscopy. Rectal carcinoids detected incidentally are usually in earlier stages at diagnosis. Rectal carcinoids estimated endoscopically as < 10 mm in diameter without atypical features and confined to the submucosal layer can be removed endoscopically. Here, we review the efficacy and safety of various endoscopic treatments for small rectal carcinoid tumors, including conventional polypectomy, endoscopic mucosal resection (EMR), cap-assisted EMR (or aspiration lumpectomy), endoscopic submucosal resection with ligating device, endoscopic submucosal dissection, and transanal endoscopic microsurgery. It is necessary to carefully choose an effective and safe primary resection method for complete histological resection.
Carcinoid tumor; Rectum; Polypectomy; Endoscopic mucosal resection; Endoscopic submucosal dissection
Endoscopic mucosal resection (EMR) is an endoscopic alternative to surgical resection of mucosal and submucosal neoplastic lesions. Prior to the development of knives, EMR could be performed with accessories to elevate the lesion. After the development of various knives, en bloc resection was possible without other accessories. So, recently, simple snaring without suction or endoscopic submucosal dissection using knife in the epithelial lesions such as adenoma or early mucosal cancer has been performed. However, for easy and complete resection of subepithelial lesions such as carcinoid tumor, a few accessories are needed. Complete resection of rectal carcinoid tumors is difficult to achieve with conventional endoscopic resection techniques because these tumors often extend into the submucosa. The rate of positive resection margin for tumor is lower in the group of EMR using a cap (EMR-C) or EMR with a ligation device (EMR-L) than conventional EMR group. EMR-C and EMR-L (or endoscopic submucosal resection with a ligation device) may be a superior method to conventional EMR for removing small rectal carcinoid tumors.
Endoscopic mucosal resection; Cap; Band ligation
In this review article the surgical technique of Transanal Endoscopic Microsurgery (TEMS) is examined. A number of techniques have been used to treat adenomas of the rectum. The treatment of large adenomas which occupy a large surface of the rectal lumen or adenomas which are flat and grow in a "carpet-like" fashion is particularly challenging. Major rectal surgery carries a risk of morbidity and mortality, particularly in elderly and unfit patients. Although local excision with transanal resection (TAR) and the Kraske sacral operation have been used in the past, during the last twenty years TEMS has become the method of choice for those lesions. TEMS is efficient and minimally invasive. The technique allows the patient to recover rapidly and the incidence of complications is much lower than that of major surgery. In case of recurrence the option of repeat TEMS or major surgery remain available. TEMS has been slow to gain popularity mainly for reasons of cost and steep learning curve but it is now an established procedure and a valuable therapeutic option which is particularly useful for elderly and unfit patients. Gastroenterologists should be aware of the nature and indications of TEMS in order to advise and refer selected patients with rectal adenomas accordingly.
Transanal endoscopic microsurgery was introduced in the early 1980s. Since then, increasing numbers of rectal adenomas are being excised by this technique. The aim of this study was to evaluate our institution's experience with transanal endoscopic microsurgery for rectal adenoma and carcinoma.
Seventy-five patients (adenomas, n=58) underwent more than 90 TEM resections over a period of 5 years.
Postoperative complications were minimal with 3% (n=2) in the adenoma group requiring transfusion and 0% 30-day mortality. One patient in each group developed transient fecal incontinence. During the follow-up period, 6 patients (10%) in the adenoma group underwent further local resections for their recurrences. Two patients in the carcinoma group (1 each of pathological T1 and T2 stage) developed recurrence at 24 months. A female with a T2 tumor was found to have an inoperable lesion and underwent sigmoid colostomy. Five of 17 patients had postoperative radiotherapy, and 2 patients developed radiation enteritis. Four patients died during follow-up due to unrelated reasons.
The transanal endoscopic microsurgery technique appears to be safe and associated with minimal morbidity. Careful selection of patients with thorough preoperative assessment is necessary for carcinoma patients. Patients with T1 lesions and favorable histology should only be considered for curative resection by this technique.
Transanal endoscopic microsurgery; Rectal adenoma; Rectal carcinoma; Local resection
Introduction. Despite initial enthusiasm, the use of transanal endoscopic microsurgery (TEM) is still quite limited at present because of the expense of highly specialized equipment and the complexity of the learning curve. Furthermore, some authors report a relevant, although temporary, effect on anorectal function because of the considerable anal dilatation which can even produce a rupture of the internal anal sphincter. The “glove TEM” proposes itself as an alternative to traditional TEM that could settle these problems. Materials and Methods. The technique is accurately described together with the necessary equipment to perform it. Between 2011 and 2012, we operated eight patients with this technique for rectal adenomas or early carcinomas achieving R0 resection in all cases and reporting no early or late complications during the first five months of followup. Discussion. This technique offers multiple advantages compared to the original TEM. (i) It allows the use of all available laparoscopic instruments. (ii) It gives a great manoeuvrability of the instruments in contrast to rigid rectoscope systems. (iii) Given the limited length of the device, it permits to operate on tumors closer to the dentate line. (iv) It is less traumatic to the anal sphincter. It is definitively much cheaper. Conclusions. We believe that this new technique is easy to perform, cost-effective, and less traumatic to the anal sphincter compared to traditional TEM.
AIM: To evaluate the proportion of successful complete cure en-bloc resections of large colorectal polyps achieved by endoscopic mucosal resection (EMR).
METHODS: Studies using the EMR technique to resect large colorectal polyps were selected. Successful complete cure en-bloc resection was defined as one piece margin-free polyp resection. Articles were searched for in Medline, Pubmed, and the Cochrane Control Trial Registry, among other sources.
RESULTS: An initial search identified 2620 reference articles, from which 429 relevant articles were selected and reviewed. Data was extracted from 25 studies (n = 5221) which met the inclusion criteria. All the studies used snares to perform EMR. Pooled proportion of en-bloc resections using a random effect model was 62.85% (95% CI: 51.50-73.52). The pooled proportion for complete cure en-bloc resections using a random effect model was 58.66% (95% CI: 47.14-69.71). With higher patient load (> 200 patients), this complete cure en-bloc resection rate improves from 44.19% (95% CI: 24.31-65.09) to 69.17% (95% CI: 51.11-84.61).
CONCLUSION: EMR is an effective technique for the resection of large colorectal polyps and offers an alternative to surgery.
Meta-analysis; Systematic review; Polyps; Endoscopic mucosal resection; En-bloc resection
Transanal endoscopic microsurgery as a local therapy option for rectal neoplasms is a tissue-sparing technique that protects the anal sphincter. The present retrospective analysis reports the course of observation after local excision of adenomas and T1 low-risk carcinomas using transanal endoscopic microsurgery.
In a retrospective analysis we examined data on 279 patients for local recurrence. A total of 144 patients had a rectal adenoma (n = 103) or a R0 resection of low-risk T1 carcinomas (n = 41). In this collective, we also examined parameters concerning perioperative management, complications, intraoperative blood loss and duration of hospital stay.
Patients with adenoma were on average 64.9 (range 37 to 90) years old; 83.5% of the adenomas were located 3 to 11 cm from the anocutaneous line. In adenoma patients the recurrence rate was 2.9% for an observation period of 21.8 months. The postoperative course was without any complications in 98.1% of patients.
Patients with T1 low-risk carcinoma were 64.6 (range 30 to 89) years old. In all cases, an R0 resection could be performed. The recurrence rate was 9.8% for an observation period of 34.4 months. In this group the postoperative course was free of complications in 97.6% of patients.
The high efficacy of transanal endoscopic microsurgery ensures minimally invasive treatment of adenomas and low-risk T1 carcinomas with low complication rates and a low rate of therapeutic failure.
Transanal endoscopic microsurgery; Rectal adenoma; Rectal carcinoma; Local excision; Endoscopic surgery
Endoscopic resection is an effective treatment for non-invasive esophageal squamous cell neoplasms (ESCNs). Endoscopic mucosal resection (EMR) has been developed for small localized ESCNs as an alternative to surgical therapy because it shows similar effectiveness and is less invasive than esophagectomy. However, EMR is limited in resection size and therefore piecemeal resection is performed for large lesions, resulting in an imprecise histological evaluation and a high frequency of local recurrence. Endoscopic submucosal dissection (ESD) has been developed in Japan as one of the standard endoscopic resection techniques for ESCNs. ESD enables esophageal lesions, regardless of their size, to be removed en bloc and thus has a lower local recurrence rate than EMR. The development of new devices and the establishment of optimal strategies for esophageal ESD have resulted in fewer complications such as perforation than expected. However, esophageal stricture after ESD may occur when the resected area is larger than three-quarters of the esophageal lumen or particularly when it encompasses the entire circumference; such a stricture requires multiple sessions of endoscopic balloon dilatation. Recently, oral prednisolone has been reported to be useful in preventing post-ESD stricture. In addition, a combination of chemoradiotherapy (CRT) and ESD might be an alternative therapy for submucosal esophageal cancer that has a risk of lymph node metastasis because esophagectomy is extremely invasive; CRT has a higher local recurrence rate than esophagectomy but is less invasive. ESD is likely to play a central role in the treatment of superficial esophageal squamous cell neoplasms in the future.
Endoscopic submucosal dissection; Esophageal cancer; Esophageal neoplasm
The authors present a woman suffering from McKittrick-Wheelock syndrome (MKWS) with a giant rectal villous adenoma. MKWS is a rare disorder caused by fluid and electrolyte hypersecretion from a rectal tumor. The most frequently reported tumors are villous adenomas. Symptoms of dehydration with severe hyponatremia, hypokalemia, metabolic acidosis and acute renal failure are typical in MKWS. Several options for operation have been reported, such as a transsacral approach (according to Kraske), transanal endoscopic microsurgery (TEM) or total mesorectal excision (TME). In this case we report an alternative surgical approach: in-one-continuity transanal mucosectomy and transabdominal TME with a handsewn colonic-anal anastomosis.
A 54-year-old woman had a history of hospital admissions because of repeated bouts of dehydration with electrolyte disorders since 2004. At admission she presented with prerenal azotemia, hyponatremia and severe hypokalemia in combination with watery stools. At colonoscopy an 8-cm villous adenoma was seen in the rectum. Dehydration and electrolyte disturbances were treated by appropriate intravenous fluid administration. An in-one-continuity anal mucosectomy and complete rectal excision were performed and restored by a handmade colonic-anal anastomosis. Postoperative recovery was uneventful.
MKWS can be a difficult problem to assess in both gastroenterological and nephrological ways. Patients may develop severe complications which require surgical intervention in some cases. In-one-continuity transanal mucosectomy and rectum excision with a handmade colonic-anal anastomosis seemed to be a new and solid surgical therapeutic option in this case.
Rectal villous adenoma; Rectal surgery; Renal failure; Dehydration; Electrolyte disorders; McKittrick-Wheelock syndrome
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.
Endoscopic submucosal dissection; Endoscopic mucosal resection; Colorectum; Laterally spreading tumor granular type; Laterally spreading tumor nongranular type
INTRODUCTION: The objective was to assess the impact on the management of colorectal patients treated in a district general hospital within the first year after the introduction of transanal endoscopic microsurgery (TEM). PATIENTS AND METHODS: Data were collected for consecutive unselected patients who underwent TEM. Comparative data were derived from a matched group of patients who underwent anterior resection, peranal procedures (PAR) or transanal resection (TAR) in this unit. RESULTS: Twenty-two patients underwent TEM (11 men and 11 women; aged, 29-87 years; median, 75 years). Eighteen patients had a pre-operative diagnosis of benign rectal neoplasms; three were found to have invasive carcinoma, which might have been missed during TAR. Four patients had a pre-operative diagnosis of rectal cancer and TEM provided local tumour control in three cases. The operating time ranged between 20-150 min (mean, 65 min; median, 57 min). Hospital stay ranged between 0-10 days (mean, 3.7 days; median, 3 days), with a total of 97 in-patient days for the entire group of patients. Twenty-four operations were performed (22 TEM and two salvage anterior resections), with an estimated cost of 1544 pounds sterling for consumables used. Alternative treatments in the absence of TEM were considered to involve 10 anterior resections, 5 closures of ileostomy, 30 TAR procedures and one PAR procedure, with an estimated 306 days of in-patient admission, 46 operations and 6245 pounds sterling spent on consumables. CONCLUSIONS: Availability of TEM allows more efficient treatment for a significant number of patients with rectal tumours. The cost of the equipment is offset by a significant decrease in the length of in-patient admissions.
Transanal excision of rectal polyps with laparoscopic instrumentation and a single incision laparoscopic port is a novel technique that uses technology originally developed for abdominal procedures from the natural orifice of the rectum. Transanal endoscopic microsurgery (TEM) is a well established surgical approach for certain benign or early malignant lesions of the rectum, under specific indications. Our technique is a hybrid technique of transanal surgery, a reasonable method for polyp resection without the need of the sophisticated and expensive instrumentation of TEM which can be applied whenever endoscopic or conventional transanal surgical removal is not feasible.
Polypectomy; SILS; Transanal endoscopic microsurgery; Laparoscopy; Endoscopy
Endoscopic resection has proven to be a safe and effective alternative to surgery for duodenal adenomas. However, few data are available on the adequacy of resection and long-term outcomes. This study evaluated the efficacy and longterm endoscopic findings in a cohort of Korean patients who underwent endoscopic mucosal resection (EMR) of sporadic duodenal adenomas.
Seventeen patients with nonampullary duodenal adenomas without familial polyposis syndrome and who were treated by EMR between January 2001 and December 2007 were evaluated retrospectively. Their management, follow-up, and outcomes were reviewed.
In total, seventeen lesions were removed from EMR in 17 patients (mean age, 59.3 years; 6 women, 11 men). The mean size of the tumors was 15.1 mm (median, 13 mm, range, 8-27 mm). Of these 17 adenomas, 16 adenomas were tubulous and 1 was tubulovillous. The EMR was performed successfully in all 17 patients in a single session. After a median follow-up period of 29 months (range, 13-72 months), all patients remained in remission. One patient had bleeding at the site of the EMR. There were no perforations after the EMR.
EMR for sporadic duodenal adenomas seemed to be a safe and effective treatment modality.
Duodenal neoplasm; Adenoma; Endoscopic mucosal resection; Treatment efficacy
Clinical implementation and widespread application of natural orifice translumenal surgery (NOTES) has been limited by the lack of specialized endoscopic equipment, which has prevented the ability to perform complex procedures including colorectal resections. Relative to other types of translumenal access, transanal NOTES using transanal endoscopic microsurgery (TEM) provides a stable platform for endolumenal and direct translumenal access to the peritoneal cavity, and specifically to the colon and rectum. Completely NOTES transanal rectosigmoid resection using TEM, with or without transgastric endoscopic assistance, was demonstrated to be feasible and safe in a swine survival model. The same technique was successfully replicated in human cadavers using commercially available TEM, with endoscopic and laparoscopic instrumentation. This approach also permitted complete rectal mobilization with total mesorectal excision to be performed completely transanally. As in the swine model, transgastric and/or transanal endoscopic assistance extended the length of proximal colon mobilized and overcame some of the difficulties with TEM dissection including limited endoscopic visualization and maladapted instrumentation. This extensive laboratory experience with NOTES transanal rectosigmoid resection served as the basis for the first human NOTES transanal rectal cancer excision using TEM and laparoscopic assistance. Based on this early clinical experience, NOTES transanal approach using TEM holds significant promise as a safe and substantially less morbid alternative to conventional colorectal resection in the management of benign and malignant colorectal diseases. Careful patient selection and substantial improvement in NOTES instrumentation are critical to optimize this approach prior to widespread clinical application, and may ultimately permit completely NOTES transanal colorectal resection.
Colorectal diseases; Transanal endoscopic microsurgery; Natural orifice translumenal endoscopic surgery
To describe the implementation of a formal single-operator led endoscopic mucosal resection (EMR) service in a district general hospital, and the effect on patient outcome of this service development.
Prospective audit during initiation and subsequent development of EMR service.
District general hospital.
All patients referred to EMR service between 1 January 2008 and 31 December 2011.
Nil in addition to clinical care.
Main outcomes measured
The number of EMRs per year including polyp size and histology, recurrence of polyp tissue at 3 months following EMR, and complications including early/delayed bleeding and perforation.
Following service implementation, the number of EMRs rose from 11 in 2008 to 35 in 2011, with the number of large polyps (>30 mm) rising from four in 2008 to 24 in 2011. Recurrent or residual adenomatous tissue fell from 75% in 2008 to 4.76% in 2011. Only one perforation occurred over the 4 years (0.8% perforation rate: 1 in 120 polypectomies). A reduction in surgical intervention for adenomatous polyp removal was observed during the audit period.
Professional engagement and support by medical, surgical and nursing members of the endoscopy team promoted development of skill and confidence in EMR. Exposure to higher volumes of EMR procedures allowed successful removal of larger lesions, while maintained patient safety and reduced the need for surgical removal of benign polyps.
ENDOSCOPY; POLYP; CANCER; ADENOMA; ENDOSCOPIC POLYPECTOMY
Endoscopic submucosal dissection (ESD) is becoming a popular procedure for the diagnosis and treatment of superficial mucosal lesions, and has the advantage of en bloc resection which yields a higher complete resection and remission rate compared to endoscopic mucosal resection (EMR). However, the learning process of this advanced endoscopic procedure requires a lengthy training period and considerable experience to be proficient. A well framed training protocol which is safe, effective, easily reproducible and cost-effective is desirable to teach ESD. In addition, the training course may need to be tailored around settings such as ethnicity, culture, workload, and disease incidence. In Asian countries with a large volume of early gastric lesions which need endoscopic treatment, endoscopists would be able to learn ESD expanding their skills from EMR to ESD under the supervision of experts. Whereas, in Western countries due to the low incidence of superficial gastric tumors, trials have utilized simulator models to improve learning. In Korea, the Korean Society of Gastrointestinal Endoscopy (KSGE) is playing an important role in training many gastroenterologists who have shown an interest in performing ESD by providing an annual live demonstration and a nationwide tutoring program. The purpose of this article is to introduce our ESD tutoring experience, review the published papers related to this topic, and propose several suggestions for future directions in teaching and learning ESD.
Endoscopic submucosal dissection; Learning; Teaching
Endoscopic submucosal dissection (ESD) is an advanced technique of therapeutic endoscopy alternative to endoscopic mucosal resection (EMR) for superficial gastrointestinal neoplasms >2 cm. ESD allows for the direct dissection of the submucosa and large lesions can be resected en bloc. ESD is not limited by resection size, increases histologically complete resection rates and may reduce the local recurrence.
Nevertheless, the technique is time-consuming, technically demanding and associated with a high complication rate. To reduce the risk of complications, different devices and technical advances have been proposed with conflicting results and, still, ESD en bloc resections of huge lesions are associated with increased complications.
We successfully used a combined ESD/EMR technique for huge rectal laterally spreading tumors (LSTs). ESD was used for circumferential resection of 2/3 of the lesion followed by piecemeal resection (2-3 pieces) of the central part of the tumour.
In all three patients we obtained the complete dissection of the polyp and the complete histological evaluation in absence of complications and recurrence at 6 months' follow up.
In the treatment of rectal LSTs, the combined treatment - ESD/EMR resection may be considered a suitable therapeutic option, indicated in selected cases as an alternative to surgery, in which the two techniques are neither reliable nor safe separately. However, to confirm our results, larger trials with longer follow up are required together with improvement of the technique and of the technical devices.
Piecemeal endoscopic mucosal resection (EMR) is generally indicated for laterally spreading tumors (LST) >2 cm in diameter. However, the segmentation of adenomatous parts does not affect the histopathological diagnosis and completeness of cure. Thus, possible indications for piecemeal EMR are both adenomatous homogenous-type granular-type LST (LST-G) and LST-G as carcinoma in adenoma without segmentalizing the carcinomatous part. Diagnosis of the pit pattern using magnifying endoscopy is essential for determining the correct treatment and setting segmentation borders. In contrast, endoscopic submucosal dissection (ESD) is indicated for lesions requiring endoscopic en bloc excision, as it is difficult to use the snare technique for en bloc excisions such as in non-granular-type LST (LST-NG), especially for the pseudodepressed type, tumors with a type VI pit pattern, shallow invasive submucosal carcinoma, largedepressed tumors and large elevated lesions, which are often malignant (e.g. nodular mixed-type LST-G). Other lesions, such as intramucosal tumor accompanied by submucosal fibrosis, induced by biopsy or peristalsis of the lesion; sporadic localized tumors that occur due to chronic inflammation, including ulcerative colitis; and local residual early carcinoma after endoscopic treatment, are also indications for ESD. In clinical practice, an efficient endoscopic treatment with segregation of ESD from piecemeal EMR should be carried out after a comprehensive evaluation of the completeness of cure, safety, clinical simplicity, and cost–benefit, based on an accurate preoperative diagnosis.
colorectal tumor; endoscopic mucosal resection (EMR); endoscopic submucosal dissection (ESD); laterally spreading tumor (LST)
Since its introduction in 1983, transanal endoscopic microsurgery (TEM) has emerged as a safe and effective method to treat rectal lesions including benign tumors, early rectal cancer, and rectal fistulas and strictures. This minimally invasive technique offers the advantages of superior visualization of the lesion and greater access to proximal lesions with lower margin positivity and specimen fragmentation and lower long-term recurrence rates over traditional transanal excision. In addition, over two decades of scientific data support the use of TEM as a viable alternative to radical excision of the rectum with less morbidity, faster recovery, and greater potential cost savings when performed at specialized centers.
Endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) have provided new alternatives for minimally invasive treatment of gastrointestinal adenomas and early-stage cancers that involve a minimum risk of lymph-node metastasis. The use of submucosal injections is essential to the success of these endoscopic resection techniques. The “ideal” submucosal injection solution should provide a sufficiently high submucosal fluid cushion for safe and effective EMRs and ESDs while also preserving lesion tissue for accurate histopathological assessment. In the past, normal saline (NS) solution was commonly used for this purpose, but it is difficult to achieve the proper submucosal elevation and maintain the desired height with NS. Therefore, other safe and effective facilitative submucosal injection solutions have been developed that also take into account relevant cost-benefit considerations. This review examines recent advances in the development of effective submucosal injection solutions for use during endoscopic resections.
submucosal injection solution; endoscopic mucosal resection (EMR); endoscopic submucosal dissection (ESD); gastrointestinal tract
A 62-year-old male patient underwent endoscopic mucosal resection (EMR). Additional hybrid 2-port hand-assisted laparoscopic surgery (HALS) (Mukai's operation) was performed for early rectal cancer located at the distal border of the rectum/below the peritoneal reflection (Rb) region [SM massive invasion/ly+/vertical margin (VM)X] via a small transverse incision, approximately 55 mm long, at the superior border of the pubic bone. After the pelvic floor muscles were dissected by laparoscopy-assisted manipulation, transanal subtotal intersphincteric resection (ISR) was performed under direct vision, securing a margin of more than 15 mm distal to the EMR scar. Partial external sphincteric resection (ESR) was also performed to obtain an adequate VM at the posterior region of the EMR scar. After bowel reconstruction, the layers were sutured transanally and a temporary covering colostomy was created. The resected specimen contained no residual tumor cells without lymph node metastasis. At 3 months after the operation, digital examination revealed good tonus of the anal muscles without stricture. The patient is currently undergoing rehabilitation of his anal sphincter muscles in preparation for the colostomy closure. In conclusion, subtotal ISR combined with partial ESR may decrease the need to perform Miles' operation for T1/2 stage I rectal cancer located at the distal border of the Rb region.
AIM: To evaluate if traction-assisted endoscopic mucosal resection (TA-EMR) is feasible and if it enables en bloc resection of colorectal lesions.
METHODS: Seven patients with a total of 12 colorectal adenomas were prospectively enrolled. All lesions were removed by TA-EMR: one hemostatic clip tied to a white silk suture was applied to the base of the lesion to allow traction through the working channel of the colonoscope. A conventional polypectomy snare was mounted over the suture and the lesion was pulled into the snare and resected in one piece.
RESULTS: All 12 lesions (nine sessile) were resected en bloc with free lateral and vertical margins by using this novel technique, including five lesions (5/12, 41.6%) in less-accessible positions, where TA-EMR enabled complete visualization of the base before resection. Mean longest lesion and specimen sizes were 9 mm (range: 6-25 mm) and 11 mm in diameter (range: 7-17 mm), respectively. No serious procedure-related complications were observed.
CONCLUSION: TA-EMR through the endoscope using a hemostatic clip and suture material is technically feasible. Visualization of colorectal lesions in less-accessible locations can be improved.
Traction-assisted; Endoscopic mucosal resection; Colon polyp; Colonoscopy
Transanal endoscopic video-assisted excision of benign and malignant rectal lesions with pneumorectal distension appears to optimize the visual field and avert several of the pitfalls commonly associated with transanal endoscopic microsurgery.
Transanal endoscopic microsurgery is a safe and efficacious surgical approach for local excision of benign adenomas and early-stage rectal cancer. However, utilization of the technique has been limited due to the unavailability of high-priced specialized instrumentation at many institutions and the technically demanding training required. To avoid these obstacles, we have explored an alternative approach called Transanal Endoscopic Video-Assisted excision, which combines the merits of single-port access and local transanal excision.
A disposable single-incision port is inserted into the anal canal for transanal access. The port contains 3 cannulae for introducing instrumentation into the rectal lumen, and a supplementary cannula for carbon dioxide insufflation. Pneumorectum results in rectal distention and optimizes the visual field during the procedure. Standard laparoscopic instrumentation is utilized for visualization and transanal excision of rectal pathologies.
Transanal endoscopic video-assisted excision is an innovative approach to local excision of benign and malignant rectal lesions. The approach averts several of the pitfalls commonly experienced with transanal endoscopic microsurgery. Continued investigation and development of this novel modality will be important in establishing its role in minimally invasive surgery.
Anal canal; Laparoscopy; Microsurgery; Rectal neoplasms
Compared with endoscopic submucosal dissection (ESD), endoscopic mucosal resection (EMR) is easier to perform and requires less time for treatment. However, EMR has been replaced by ESD, because achieving en bloc resection of specimens > 20 mm in diameter is difficult with EMR. The technique of ESD was introduced to resect large specimens of early gastric cancer in a single piece. ESD can provide precise histological diagnosis and can also reduce the rate of recurrence, but has a high level of technical difficulty, and is consequently associated with a high rate of complications, a need for advanced endoscopic techniques, and a lengthy procedure time. To overcome disadvantages in both EMR and ESD, various advances have been made in submucosal injections, knives, other accessories, and in electrocoagulation systems.
Endoscopic mucosal resection; Endoscopic submucosal dissection; Endoscopic device; Endoscopic mucosal resection device; Endoscopic submucosal dissection device