Colonoscopic Resection Research Articles

Large Cecal Lipoma With Overlying Ulceration Simulating Malignancy: A Case Report and Review of Relevant Literature

Gastrointestinal lipomas are rare, usually single, slow growing benign non-epithelial tumors. Most colonic lipomas are asymptomatic and are usually detected incidentally during colonoscopy, surgery or autopsy. In a small percentage of cases, especially when their diameter is greater than 2 cm, they can cause symptoms. The common presenting symptoms include constipation, diarrhea, colicky abdominal pain, change in bowel habit, bowel obstruction, lower gastrointestinal bleeding, intussusception or prolapse. Imaging techniques, including CT and MRI are regularly used. However, preoperative diagnosis of colonic lipoma is often difficult with the majority of the lesions diagnosed by laparotomy and definitive diagnosis is made based on histopathological examination. Colonoscopy permits direct visualization of the submucosal lipoma. Endoscopy can usually distinguish lipomas from other tumors. Lipomas are seen as smooth, rounded yellowish polyps with a thick stalk or broad-based attachment. Typical colonoscopy features are the “tent sign” (elevation of the mucosa over lipoma with biopsy forceps), “cushion sign” or “pillow sign” (pressing forceps against the lesion results in depression or pillowing of the mass) and the “naked fat sign” (extrusion of yellowish fat at the biopsy site. The mucosa overlying a colonic lipoma is intact. In rare cases, colonoscopy may reveal large-sized flat-shaped mass with ulceration that may lead to an impression of malignancy. Colonoscopic biopsy is often performed to determine the exact nature of the tumor. However colonic lipomas may result in mucosal inflammation of adjacent tissue giving the false impression of “nonspecific colitis” . This is particularly true in cases of inadequate tissue sample. Recently, virtual colonoscopy has been performed to detect colonic lipomas. Lipomas less than 2 cm in diameter can be removed endoscopically whereas larger lesions should be removed surgically either by open or laparoscopic methods. Colonoscopic resection of large colonic lipomas remains a controversial subject till date. Although a wide range of operative techniques including colostomy and excision, hemicolectomy or subtotal colectomy are employed, segmental resection is usually the procedure of choice. We describe a patient with persistent abdominal pain who underwent open right hemicolectomy for the presumptive endoscopic diagnosis of cecal adenocarcinoma and discuss diagnostic modalities and treatment options. Histological examination confirmed that the resected specimen was a giant benign cecal lipoma. doi: http://dx.doi.org/10.4021/jcs34w

Potential Hazards of Submucosal Injection of Methylene Blue

To the Editor: Endoscopists have routinely used submucosal injection of diluted methylene blue or indigo carmine to enhance the safety and ensure the completeness of colonoscopic resection of large, sessile polyps. Both dyes are similarly colored blue, yet important features differentiate the two. Methylene blue is a prototypical example of a vital stain, exhibiting preferential uptake by intestinal absorptive cells. By contrast, indigo carmine is not absorbed, functioning simply as an inert contrast dye.

Transanal Endoscopic Microsurgery for the Treatment of Well-Differentiated Rectal Neuroendocrine Tumors

PurposeRecently, 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.MethodsBetween 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.ResultsThe 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.ConclusionTEM might provide an accessible and effective treatment either as an initial or as an adjunct after a colonoscopic resection for a WRNET.

Colonoscopic electrosurgical resection of high-risk polyps: Pretreatment methods

Colonoscopic electrosurgical resection of high-risk polyps: Pretreatment methods

Colonoscopic Snare-assisted Transanal Resection of a Large Lipoma at the Rectosigmoid Junction

Colonic lipomas are rare benign tumors of nonepithelial origin. They are usually asymptomatic, but occasionally patients presenting with symptomatic colonic lipomas are treated with resection, either endoscopically or surgically. We report a 33-year-old woman who presented with a protruding mass at the anal orifice after defecation. She received colonoscopic snare-assisted transanal resection and pathology showed that the mass was a lipoma.

Outcomes Following Referral for Colonoscopic Resection of the “Defiant Polyps”: A Single Center Experience

Purpose: Flat and sessile lesions are being identified with increasing frequency owing to increased awareness and enhanced imaging. The “defiant polyp” [DP] is a lesion identified at colonoscopy that defies resection by standard snare polypectomy technique. Increasingly, the DP undergoes photodocumentation, tissue sampling and is referred for subsequent curative colonoscopic resection. The aim of this study was to detail the current nature of the DPs and outcomes with referral for curative colonoscopic resection. Methods: The indication term “defiant polyp” was ascribed prospectively as defined above beginning June ‘07. An electronic endoscopy report data set was searched for this indication from June’07 to Sept'09 for a single endoscopist at a tertiary center. Data pertaining to patient age and gender, polyp site and histopathology, resection technique, use of adjunctive ablation, adverse events, and residual/recurrent neoplasia at follow up were culled. Patients underwent resection following submucosal injection of varying quantities of normal saline solution tinted with Methylene blue dye. Standard and min-snares were used with pure coagulation current. Results: Two hundred seventy six patients (50.4% Female, age 65; SD12) with a total of 302 DP were identified for resection. The morphology of DPs according to Paris classification was Ip 22, Is 196, IIa 82, IIb 2. The majority of DPs were located in the right colon (218; 72%). The mean size was estimated as 23 mm (8-100 mm, SD12). In 29 (9.6%), endoscopic resection was deemed unsuitable due to unfavorable appearance (7), access (12), or non-lifting (10). Endoscopic complete eradication (R0) was achieved in a single session in 268 of DPs (98.2%). Five polyps required up to 3 additional sessions for R0. En bloc resection was done in 146 polyps (53.5%)and piecemeal in 126 (46.2%). Histopathology revealed 173 tubular adenomas (61.1%), 57 serrated adenomas (20.1%), 26 tubulo-villous adenomas (9.2%), 17 hyperplastic polyps (6%) and 10 adenocarcinomas (3.5%). Adjunctive ablation of focal residual neoplastic tissue was applied in 66 cases (24.2%) to achieve R0. Procedure related adverse events were recorded in 22 (9.5%) of 231 patients. Acute bleeding occurred in 7 patients (one required hospitalization and repeat endoscopy). There was one microperforation managed with clip closure and antibiotics. Delayed bleeding (1 to 6 days post procedure) was observed in 14 patients (6.1%) of whom 8 patients required hospitalization and 4 patients colonoscopy for haemostasis. Conclusion: DPs consist predominantly of sessile and flat adenomas including serrated adenomas. Most DPs can be successfully eradicated at dedicated therapeutic colonoscopy using adjunctive resection and ablation techniques. The R0 rate is high and adverse events are low.

Endoscopic resection of very large submucosal tumors in the colon is feasible

Introduction: Submucosal tumors of the colon are rare and usually incidental findings causing no symptoms. Lesions bigger than 2cm are usually resected surgically if the cause symptoms as endoscopic resection is associated with an elevated risk for perforation. Patient and Method: We report on a 57 year old patient who underwent colonoscopy because of recurrent abdominal pain, intermittent constipation and a positive fecal occult blood test. A large submucosal tumor with a short stalk was found in the ascending colon. Because of the symptoms and the size of the lesion the patient was scheduled for surgery. Due to concomitant diseases like COPD Gold III, hypertension and massive obesity the patient was regarded as high risk and colonoscopic resection with surgical stand-by was planned. Because of the huge size, placement of an Endo-Loop® (Olympus Corp.) was not possible. The tumor was therefore resected using a Jumbo Captivator Snare® (Boston Scientific). The area of resection was closed using six Resolution Clips® (Boston Scientific). No complication occurred and the patient was discharged the next day. Results: The resected specimen measured 5.5cm in diameter. Histopathological work-up revealed a lipoma, resected completely and in one piece. Discussion: Only five cases of endoscopic resection of submucosal tumors measuring 5cm or more in diameter have been published so far. Perforation occurred once in a sessile lesion. Endoscopic removal of very large submucosal tumors is feasible and seems to be reasonably save even without prior placement of an Endo-Loop®. However, interdisciplinary management of such cases is mandatory in order to maximize patient's safety and to deal with potential complications like perforation or hemorrhage. Endoscopic resection of very large submucosal tumors seems to be a viable treatment option for symptomatic patients unfit for surgery.

M1550: Preliminary Outcomes Following Referral for Colonoscopic Resection of the “Defiant Polyp” Identified At Screening Colonoscopy

M1550: Preliminary Outcomes Following Referral for Colonoscopic Resection of the “Defiant Polyp” Identified At Screening Colonoscopy

Endoscopic Diagnosis and Treatment of Colorectal Cancers

Colonoscopy is the best screening tool to detect colorectal cancer in early stage and also a potent arm to prevent development of cancer by removing colorectal adenoma. Superficial colorectal neoplastic lesions are primary targets of colonoscopic resection. Adenoma, carcinoma in situ, and cancer with minimal submucosal invasion are included in this category. One stage endoscopic treatment without the preceding biopsy confirmation is preferable, and thus endoscopic evaluation to identify the characteristics of the superficial neoplastic lesions is of importance. Gross endoscopic appearance and pit pattern and/or vascular pattern of the surface epithelium of the polypoid and nonpolypoid superficial lesions provide useful clue to predict histology of the lesions and depth of cancer invasion with reasonable accuracy. Appropriate treatment can be directed through this endoscopic evaluation step. Conventional snare polypectomy and endoscopic mucosal resection is mainstay of endoscopic treatment. Recently introduced endoscopic submucosal dissection facilitated en bloc resection of a large neoplastic lesion. After endoscopic resection, accurate pathologic evaluation is necessary to determine whether colonoscopic follow up or further surgical resection is needed. Poorly or undifferentiated cancers, cancers massively invading submucosal layer deeper than 1,000 micrometer, lymphovascular invasion of cancer cells, or presence of cancer cells on the resection margin are indications of further surgical resection because of the significant risk in metastasis to the regional lymph nodes. Colorectal polyps and early cancers are effectively treated by colonoscopy in most cases. Early detection by an adequate screening program is essential for this purpose.

Reply to: doi:10.1007/s00464-009-0668-z: Combined laparoscopic–endoscopic resection of colorectal polyps: 10-year experience and follow-up evaluation

This article tries to answer the question about the feasibility of laparoscopically assisted resection of difficult ‘‘benign’’ polyps. It would have been useful if the data presented had been contextualized with regard to the number of patients who underwent alternative or open procedures? Primarily, open resection of benign, even difficult polyps, is no longer the therapy of choice and almost dispensable since the introduction of combined procedures to our department in the early 1990s. Thus, all patients received the combined approach at first. Seven patients (5%) underwent conversion to open surgery due to suspicion of malignant disease (n = 3, according to institutional policy), bowel perforation during colonoscopy (n = 1), difficult closure of the colotomy (n = 2), and incomplete resection of a rectal lesion (n = 1). This was clearly stated in the article. If the polyps were classified as endoscopically resectable in a routine preoperative endoscopic examination, this was the preferred therapy. The definition of polyps deemed unresectable by colonoscopy was accepted as subjective. However, was there any screening or repeat colonoscopy by an experienced colonoscopist? All the patients had received a colonoscopy by an experienced endoscopist before presenting to our institution. However, preoperative recolonoscopy routinely performed could preserve about 5% of patients from surgical treatment. Concrete endoscopic snare resection had even been attempted for 27 of the patients but was unsuccessful. Moreover, we note that with laparoscopic assistance, only eight polyps were endoscopically approachable, as displayed in Table 2. Voloyiannis et al. [1] found that selective colonoscopy for 171 of 252 patients referred led to avoidance of resection for 101 patients. As a result, 58% of these were rescoped, and 40% of all the patients referred avoided resection. This resection rate may improve with the relatively new technique of colonoscopic (endoscopic) mucosal resection described by Saito et al. [2]. The percentage of resections avoided by recolonoscopy was comparably low in our series, as already mentioned. However, all referring practitioners are highly experienced endoscopists, and the low avoidance rate may be due to the fact that the classification of polyps as unresectable is justified to a great extent. The technique of endoscopic submucosal dissection for large colonic adenomas, as described by Saito et al. [2], is very demanding but attracting initial interest in Japan. In the Western world, endoscopic submucosal resection still is in its infancy and not a standard procedure. Additionally, it is associated with a much higher complication rate. The authors are to be complimented for their honest appraisal of complications at 25%. D. Wilhelm (&) H. Feussner Department of Surgery, Technische Universitat Munchen, Klinikum rechts der Isar, Ismaninger Strasse 22, 81675 Munich, Germany e-mail: wilhelm@chir.med.tu-muenchen.de

Colonoscopic Full-Thickness Resection Followed By Tissue Apposition - An Option for Recurrent Colon Polyps Tethered to the Colonic Wall with Scar Tissue

Colonoscopic Full-Thickness Resection Followed By Tissue Apposition - An Option for Recurrent Colon Polyps Tethered to the Colonic Wall with Scar Tissue

Con: Colonoscopic Resection of Large Neoplastic Lesions Is Appropriate and Safe

Con: Colonoscopic Resection of Large Neoplastic Lesions Is Appropriate and Safe

Laparoscopic colectomy for colonic polyps

Benign colonic polyps not amenable to colonoscopic resection or those containing carcinoma require surgical excision. Traditionally, formal colectomy with clearance of the lymphatic basin has been performed. The aim of this study was to review our experience with the laparoscopic approach for retrieval of colonic polyps with specific emphasis on safety, feasibility, and tumor localization. Retrospective chart review of all patients who underwent laparoscopic colectomy for colonic polyps was performed. Initial colonoscopic biopsies were compared with the postoperative pathology report of the resected specimen. Forty-nine patients (22 males, 27 males, mean age 66 years) underwent laparoscopic colectomy for colonic polyps. Indications for surgery were presumably benign polyps in 38 patients, and superficial carcinoma in a polyp, diagnosed by colonoscopy, in 11; twenty-three patients underwent preoperative localization procedures. In 19% of patients who did not have preoperative localization, difficulties locating the polyp were encountered during surgery, requiring intraoperative endoscopy or conversion to laparotomy. In 7 of the 38 patients with presumably benign lesion, colon cancer was diagnosed in the colectomy specimen. None of the 18 patients who had cancerous lesions had any positive lymph nodes. Laparoscopic surgery for the treatment of colonic polyps seems to be feasible and safe, with a low complication rate. Tumor localization is crucial for adequate resection. Although one-fifth of presumably benign polyps harbored cancer, none of these patients had positive lymph nodes. These preliminary results may question the need for radical lymph node clearance in these patients.

McKittrick-Wheelock Syndrome Treated by Laparoscopy

To present 3 cases of secreting villous adenoma (McKittrick-Wheelock syndrome) successfully treated with laparoscopic surgery. We present 3 cases, characterized by chronic diarrhea and requiring hospitalization owing to electrolyte and fluid depletion with acute renal failure. Owing to the extension and location of the adenomas, laparoscopic surgery (low anterior resection or procto-sigmoidectomy resection) was performed after medical treatment and endoscopic diagnosis. Postoperative recovery was satisfactory. When colonoscopic resection is not feasible in cases of secreting villous adenomas owing to their size or location, laparoscopic surgery in expert hands is a safe, effective, and complete option, further enhanced by the benefits of minimally invasion surgery.

Simulation of a colorectal polypoid lesion—a pilot porcine model

Large sessile polyps almost always contain villous tissue with appreciable premalignant potential and tend to recur locally after colonoscopic resection. Developing new endoscopic techniques for the removal of polyps requires a large animal model of colorectal polypoid lesions. So far, no appropriate large animal model of a colorectal or other GI polyp has been described in the English literature. Our purpose was to develop a large animal model simulating large, perfused and viable, sessile colorectal polypoid lesions, with distinct easily detectable histologic features. An animal laboratory. Two simulated rectal polyps, using 2 different techniques, were created in each of 10 animals. The polyps were simulated by ovarian tissue that was introduced either intraluminally through the rectal wall or into a dissected submucosal space in the rectal wall. In 2 animals the created polyps were endoscopically resected. All submucosal lesions were sessile-like polypoid lesions because the base of the polyp was the widest diameter of the lesion. All transmural polypoid lesions had short and thick pedicles. Resection by snaring and cutting was demonstrated to be feasible. The mean measurements of the submucosal-simulated polyps were as follow: 1.74 cm (+/-0.32) x 2.07 cm (+/-0.42) x 1.51 cm (+/-0.27). The mean measurements of the transmural-simulated polyps were significantly larger: 2.55 cm (+/-0.52) x 3.57 cm (+/-1.1) x 2.7 cm (+/-0.64). This model does not simulate a real intestinal neoplasia. Either method, the submucosal or the transmural, could be helpful in the research and development efforts of surgical and endoscopic treatments of intestinal polyps.

Efficacy, risk factors and complications of endoscopic polypectomy: Ten year experience at a single center

To examine the efficacy and complications of colonoscopic resection of colorectal polypoid lesions. We retrospectively reviewed 1354 polypectomies performed on 1038 patients over a ten-year period. One hundred and sixty of these were performed for large polyps, those measuring > or = 20 mm. Size, shape, location, histology, the technique of polypectomy used, complications, drugs assumption and associated intestinal or extra intestinal diseases were analyzed. For statistical analysis, the Pearson chi2 test, NPC test and a Binary Logistic Regression were used. The mean patient age was 65.9 +/- 12.4 years, with 671 men and 367 women. The mean size of polyps removed was 9.45 +/- 9.56 mm while the size of large polyps was 31.5 +/- 10.8 mm. There were 388 pedunculated and 966 sessile polyps and the most common location was the sigmoid colon (41.3%). The most frequent histology was tubular adenoma (55.9%) while for the large polyps was villous (92/160 -57.5%). Coexistent malignancy was observed in 28 polyps (2.1%) and of these, 20 were large polyps. There were 17 procedural bleeding (1.3%) and one perforation. The statistical analysis showed that cancer is correlated to polyp size (P < 0.0001); sessile shape (P < 0.0001) and bleeding are correlated to cardiac disease (P = 0.034), tubular adenoma (P = 0.016) and polyp size. The endoscopic resection is a simple and safe procedure for removing colon rectal neoplastic lesions and should be considered the treatment of choice for large colorectal polyps. The polyp size is an important risk factor for malignancy and for bleeding.

Lateral spreading tumors (LST) and colonoscopic resection: A prospective analysis

Lateral spreading tumors (LST) and colonoscopic resection: A prospective analysis

Transabdominal Transcolonic Polypectomy

Up until now, 2%-10% of colonic polyps larger than 2 cm have been considered colonoscopically unresectable. These were commonly treated by piecemeal resection and observation by colonoscopists and hemicolectomy by surgeons. Our minimally invasive "rural solution" in this situation is transcolonic resection through a mini-laparotomy. We present 7 patients with large colonic villous adenomas not amenable to colonoscopic resection. Laporoscopy determined the location of the muscle-splitting incision. The segment of bowel containing the polyp was exteriorized: antimesentric polyps were excised together with the corresponding colonic wall; polyps in mesenteric location were removed transmurally through an anterior colotomy. There was no surgical morbidity. Five of the 7 patients were discharged within 24 hours. Preoperative tattooing of the lesions and laparoscopic mobilization of the involved segment--when necessary--proved to be useful adjuncts. This seems to be an attractive option that may be superior to formal colectomy or repeated endoscopic piecemeal excision of large polyps. It provides colonoscopists with the option of avoiding having to resect very difficult polyps while not subjecting their patients to unnecessarily morbid operations.

Update on colorectal polyps: management and follow-up surveillance.

Available scientific data and considerable clinical experience indicate that over 95 % of colorectal cancers arise in benign adenomatous polyps that develop and advance very slowly over many years. Interruption of this adenoma-carcinoma sequence by finding and resecting polyps is a highly effective method of preventing colorectal cancer. Colonoscopy is the procedure of choice for both the diagnosis and resection of colorectal polyps. Patients who have had colonoscopic resection of adenomas, and in some cases their close relatives, are at a higher than average risk for developing future polyps and cancer, and likely will benefit from periodic follow-up colonoscopic surveillance. This surveillance should to be tailored to the perceived risk of each individual case depending on the features of the resected adenomas and other patient factors such as family history. Widespread adoption of current polyp guideline recommendations would be highly protective and yet would conserve medical resources.

Metachronous colon tumors: risk factors and rationale for the surveillance colonoscopy after initial polypectomy.

We analyzed the possible risk factors for metachronous colon tumors after endoscopic resection of initial tumors. Three hundred and twenty-one patients entered the surveillance study after colonoscopic resection of initial tumors between 1985 and 1999. Histology of initial tumors was adenoma in 214 patients and carcinoma in 107 patients. Solitary tumor was observed in 196 patients and multiple tumors in 125 at initial endoscopy. The median surveillance period was 39 (range, 12-112) months, and the median frequency of surveillance colonoscopy was three (range, 2-10) times. Metachronous neoplasms were identified in 114 of 321 surveillance cases (36%). In the 114 cases, the number of patients with metachronous adenoma was 103 (90%) and that of carcinoma was 11 (10%). Clinical characteristics at entry - including age, gender, multiplicity of polyp, histology of polyp, and site of polyp - were not different between patients with metachronous tumors and those without metachronous tumors. Kaplan-Meier analysis revealed that patients with a histology of carcinoma and those with multiple polyps at entry developed metachronous tumors significantly earlier than did patients with initial adenomas and initial solitary polyp, respectively ( P<0.001, P<0.001). However, other characteristics at entry did not produce significant differences in the rate of the development of metachronous tumors using Kaplan-Meier analysis. Proportional hazards model analysis revealed that histology of the initial tumor as carcinoma (relative risk, 1.690, 95% confidence interval, 1.118-2.555) and multiplicity (1.472, 1011-2.143) were significant risk factors for metachronous colon tumors. The 75%, 50%, and 25% metachronous tumor-free periods after initial polypectomy were 14, 21, and 39 months, respectively. These results may help optimizing surveillance strategies for metachronous colon tumors and raising the economic benefit of colonoscopy.