Endoscopic features with associated histological and molecular alterations in serrated polyps with dysplasia: Retrospective analysis of a tertiary case series

BACKGROUND

Serrated polyps are incompletely understood lesions and include serrated sessile lesion (SSL) without or with dysplasia and traditional serrated adenoma (TSA).

AIMS

We investigated prevalence and characteristics of serrated lesions, especially SSL with dysplasia (mixed polyps).

METHODS

This retrospective study analyzed data from consecutive patients referred for colonoscopy at a tertiary care center. Endoscopic and histopathological characteristics of identified lesions were studied. SSLs with dysplasia were molecularly analyzed for mutations and microsatellite instability.

RESULTS

Among 1147 patients, a total of 436 polyps were found, including 288 adenomas (66.1 %) and 114 serrated lesions (SLDR 26.2 %). PDR was 34.5 % and ADR was of 30.2 %. Serrated lesions included 75 hyperplastic polyps (17.2 %), 24 SSLs without dysplasia (5.5 %), 6 SSLs with dysplasia (mixed polyps) (1.4 %) and 9 TSA (2.1 %). The mixed polyps were evaluated molecularly: these analyses found no KRAS mutation, a single NRAS mutation in one lesion, the Val600Glu BRAF mutation in four lesions in both their serrated non-dysplastic and dysplastic areas, and microsatellite instability in four lesions, limited to the dysplastic areas.

CONCLUSION

Our single-center experience confirms the high prevalence of serrated lesions, a part of which are SSL with dysplasia. These lesions seem to carry specific molecular alterations.

Diffuse xanthoma in early esophageal cancer: A case report

BACKGROUND

Gastrointestinal xanthomas are asymptomatic and infrequent non-neoplastic lesions that commonly occur in the stomach with Helicobacter pylori-associated gastritis and rarely in the esophagus. To date, there have been no reports of esophageal xanthoma combined with esophageal cancer. Herein, we present the first case in the literature of a diffuse xanthoma complicated with early esophageal cancer. Moreover, this combination makes the endoscopic diagnosis difficult if it is not in mind.

CASE SUMMARY

A 68-year-old man visited our department with a 2-mo history of epigastric discomfort. He underwent surgery for gastric cancer 6 years ago. Esophagogastroduodenoscopy showed a semi-circumferential irregular yellowish-colored and granular lesion in the esophagus (30-35 cm from the incisors). Using magnifying endoscopy with narrow band imaging, aggregated minute and yellowish-colored spots with tortuous microvessels on the surface were observed, and background coloration was clearly seen in the lesion. As endoscopic biopsy suggested a histologically high-grade dysplasia; the lesion was completely resected en bloc by endoscopic submucosal dissection (ESD). The resected specimen was confirmed to be a squamous cell carcinoma in situ with extensive foamy cells in the superficial mucosal layer. Immunohistochemically, the observed foamy cells were strongly positive for CD68, which is characteristic of xanthoma. The clinical course was favorable, and no recurrence was observed 2 years and 7 mo after ESD.

CONCLUSION

Diffuse xanthoma concurrent with early esophageal cancer is extremely rare. The characteristic endoscopic features may assist endoscopists in diagnosing similar lesions.

Endoscopic features and associated histology of an basaloid squamous cell carcinoma of the esophagus at the very early stage

Background

Basaloid squamous cell carcinoma of the esophagus (BSCCE) is generally detected at advanced stage and the prognosis is poorer than advanced conventional esophageal squamous cell carcinoma. Therefore, early detection is a critical to improve patients’ survival. However, only a few cases of early BSCCE have been reported and the endoscopic features of early BSCCE are not well described. We herein report the endoscopic features and associated histology of an early BSCCE limited within the mucosal lamina propria (m2). To our knowledge, this is the earliest BSCCE reported to date.

Case presentation

A 62-year-old male patient was admitted to our hospital because of epigastric pain for 3 months. White light endoscopy revealed a flat lesion with mild sloping at the periphery. The lesion was covered with leukoplakia, and normal vascular network could not be seen in the lesion. Magnifying endoscopy with narrow-band imaging showed abnormal intra-papillary capillary loop categorized as type B1 according to the classification of the Japan Esophageal Society. Iodine staining revealed a less-stained lesion. The lesion was completely resected through endoscopic submucosal dissection. Histopathologically, tumor cells, which were limited within the mucosal lamina propria, formed solid nests and lobule structures, with ribbon-like arrangement of sparse cytoplasm and round to ovoid hyperchromatic nuclei. A final diagnosis of early BSCCE was established.

Conclusions

This is the earliest BSCCE reported to date. The prominent lesion with a gentle rising slope and less-staining or abnormal stain might be initial feature of early BSCCE.

Neurofibromatosis type 1-associated multiple rectal neuroendocrine tumors: A case report and review of the literature

Neurofibromatosis type 1 (NF-1) is commonly associated with benign or malignant tumors in both the central and peripheral nervous systems. However, rare cases of NF-1-associated multiple rectal neuroendocrine tumors have been reported. This report describes a case of a 39 year old female with NF-1 and intermittent hematochezia as a primary symptom. Physical examination showed multiple subcutaneous nodules and café au lait spots with obvious scoliosis of the back. Imaging examinations and colonoscopy found malformation of the left external iliac vein and multiple gray-yellow nodules with varying sizes and shapes in the rectal submucosal layer. Histological and immunohistochemical results suggested multiple rectal neuroendocrine tumors, a rare disease with few appreciable symptoms and a particularly poor prognosis. The patient with NF-1 presented here had not only multiple rectal neuroendocrine neoplasms but also vascular malformations, scoliosis and other multiple system lesions. This case therefore contributes to improving clinical understanding, diagnosis and treatment of related complications for patients with NF-1 who present with associated medical conditions.

Validation study for development of the Japan NBI Expert Team classification of colorectal lesions

BACKGROUND AND AIM

The Japan narrow-band imaging (NBI) Expert Team (JNET) was organized to unify four previous magnifying NBI classifications (the Sano, Hiroshima, Showa, and Jikei classifications). The JNET working group created criteria (referred to as the NBI scale) for evaluation of vessel pattern (VP) and surface pattern (SP). We conducted a multicenter validation study of the NBI scale to develop the JNET classification of colorectal lesions.

METHODS

Twenty-five expert JNET colonoscopists read 100 still NBI images with and without magnification on the web to evaluate the NBI findings and necessity of the each criterion for the final diagnosis.

RESULTS

Surface pattern in magnifying NBI images was necessary for diagnosis of polyps in more than 60% of cases, whereas VP was required in around 90%. Univariate/multivariate analysis of candidate findings in the NBI scale identified three for type 2B (variable caliber of vessels, irregular distribution of vessels, and irregular or obscure surface pattern), and three for type 3 (loose vessel area, interruption of thick vessel, and amorphous areas of surface pattern). Evaluation of the diagnostic performance for these three findings in combination showed that the sensitivity for types 2B and 3 was highest (44.9% and 54.7%, respectively), and that the specificity for type 3 was acceptable (97.4%) when any one of the three findings was evident. We found that the macroscopic type (polypoid or non-polypoid) had a minor influence on the key diagnostic performance for types 2B and 3.

CONCLUSION

Based on the present data, we reached a consensus for developing the JNET classification.

Use of an abdominal obstetric binder in colonoscopy: A randomized, prospective trial

BACKGROUND AND AIMS

Various methods have been reported as aids to cecal intubation. This study aimed to prospectively investigate whether an abdominal obstetric binder (AOB) used during pregnancy and attached to the patients' abdomen during colonoscopy could facilitate effective colonoscopic insertion.

METHODS

This was a prospective study of 451 consecutive outpatient colonoscopies performed by a single experienced endoscopist. The recruited patients were randomly separated into two groups that received colonoscopy either with (Group A) or without an AOB attached (Group B). The cecal intubation time, cecal intubation length of the colonoscope, use of manual pressure, position change of each patient, and the number of patients with abdominal distension were collected for comparison.

RESULTS

A total of 451 patients (224 in Group A and 227 in Group B) were ultimately included in this study. In Group A, cecal intubation time and cecal intubation length of colonoscope (CIL) were significantly reduced (P < 0.001). The patients had significantly fewer position changes and manual pressure in Group A (P < 0.001). Significantly less abdominal distension was reported by patients in Group A (P < 0.001).

CONCLUSIONS

During colonoscopy, the application of an AOB provided a significantly faster and more effective colonoscope insertion.

Correlation of endoscopic images and histological findings of a high grade dysplasia developed in a gastric xanthoma

Gastric neoplasia developed in a xanthoma is very rare. We herein report a high grade dysplasia (HGD) arising in a gastric xanthoma removed by endoscopic submucosal dissection (ESD). A 57-year-old man was referred to our hospital for removal of rectal polyps. During surveillance esophago-gastro-duodenoendoscopy before polypectomy, an irregularly shaped gastric xanthoma with unusual color was found in the stomach. Although, magnifying narrow band imaging showed no typical neoplastic vessel or surface pattern on the surface and endoscopic biopsies revealed no tumor, diagnostic ESD was performed because of its irregular shape and unusual color for a commonly seen xanthoma. Histologically, a high grade dysplasia, 6 mm×6 mm in size, was detected within a gastric xanthoma. This is the first report of correlation of endoscopic images and histological findings of a HGD in a gastric xanthoma.

Traction using a clip-with-line is a preferred method for trainees in performing esophageal endoscopic submucosal dissection: an animal model study

BACKGROUND

The optimal operative process of esophageal endoscopic submucosal dissection (ESD), especially for the beginners, is not established. In this study, the clip-with-line method, the tunneling method and the conventional method for esophageal ESD were compared in a training course on live pigs.

METHODS

15 trainee endoscopists were randomized into three groups, the clip-with-line method group, the tunneling method group, and the conventional method group. Each trainee performed four esophageal ESDs on live pigs with one of the specified methods, assisted by a senior endoscopist. The procedural time and speed, the en bloc resection rates, adverse events, and self-completion rates were recorded, and learning curves were drawn.

RESULTS

The procedural time in the clip-with-line group was significantly shorter than those in the tunneling and the conventional method group (47.4 ± 9.0 min versus 67.0 ± 15.1 min and 67.0 ± 11.8 min, p = 0.000). The clip-with-line method had the lowest rates of perforation and muscle layer injury among the three methods. The en bloc resection rates and self-completion rates were similar among the three groups. Learning curves analysis showed the clip-with-line method was the easiest one for the trainees to master.

CONCLUSIONS

The clip-with-line method shortened procedural time for trainees, and was associated with lower rates of adverse events. This method is preferred for endoscopists in their learning periods for esophageal ESD.

Endoscopic Submucosal Dissection of Superficial Esophageal Neoplasms Is Feasible and Not Riskier for Patients with Liver Cirrhosis

BACKGROUND

Esophageal endoscopic submucosal dissection (ESD) has rarely been reported for the treatment of cirrhotic patients.

AIM

To report the results of ESD treatment of superficial esophageal neoplasms (SENs) for cirrhotic patients.

METHODS

Forty patients with 50 consecutive SENs undergoing 46 sessions of ESD were retrospectively reviewed. The cirrhotic group included eight patients (11 SENs) with liver cirrhosis consisting of six patients classified as Child-Pugh class A liver cirrhosis and two patients classified as class B liver cirrhosis. Four patients (6 SENs) had coexisting esophageal varices. Parameters were compared between the cirrhotic patients and the non-cirrhotic controls (32 patients, 39 SENs).

RESULTS

Platelet counts of the cirrhotic group were significantly lower, while international normalized ratio was significantly higher. When the cirrhotic group and non-cirrhotic group were compared, the mean tumor length (4 vs. 3.7 cm, p = 0.56) and median procedure time (15.1 vs. 11.5 min/cm², p = 0.30) were similar. The en bloc resection rates were 81.8 and 89.7 % (p = 0.60). Within the cirrhotic group, both lesions without en bloc resection were patients with esophageal varices. The rates of submucosal disease for the cirrhotic group and non-cirrhotic groups were 54.5 and 25.6 % (p = 0.064), respectively, while the R0 resection rates were 77.8 and 94.3 % (p = 0.16), respectively. The two lesions without R0 resection in cirrhotic group had positive vertical but not horizontal margins due to submucosal invasion. Intraprocedural bleeding occurred more frequently in cirrhotic patients than non-cirrhotic patients (18.2 vs. 0 %, p = 0.045). None of the patients suffered from esophageal perforation, postoperative bleeding, or death that was related to the ESD.

CONCLUSION

Esophageal ESD seems to be safely and can be effectively performed on cirrhotic patients, particularly those without severe liver dysfunction.

Narrow-band imaging (NBI) magnifying endoscopic classification of colorectal tumors proposed by the Japan NBI Expert Team

Many clinical studies on narrow-band imaging (NBI) magnifying endoscopy classifications advocated so far in Japan (Sano, Hiroshima, Showa, and Jikei classifications) have reported the usefulness of NBI magnifying endoscopy for qualitative and quantitative diagnosis of colorectal lesions. However, discussions at professional meetings have raised issues such as: (i) the presence of multiple terms for the same or similar findings; (ii) the necessity of including surface patterns in magnifying endoscopic classifications; and (iii) differences in the NBI findings in elevated and superficial lesions. To resolve these problems, the Japan NBI Expert Team (JNET) was constituted with the aim of establishing a universal NBI magnifying endoscopic classification for colorectal tumors (JNET classification) in 2011. Consensus was reached on this classification using the modified Delphi method, and this classification was proposed in June 2014. The JNET classification consists of four categories of vessel and surface pattern (i.e. Types 1, 2A, 2B, and 3). Types 1, 2A, 2B, and 3 are correlated with the histopathological findings of hyperplastic polyp/sessile serrated polyp (SSP), low-grade intramucosal neoplasia, high-grade intramucosal neoplasia/shallow submucosal invasive cancer, and deep submucosal invasive cancer, respectively.

Unexpected endoscopic full-thickness resection of a duodenal neuroendocrine tumor

A 57-year-old man underwent endoscopy for investigation of a duodenal polyp. Endoscopy revealed a hemispheric submucosal tumor, about 5 mm in diameter, in the anterior wall of the duodenal bulb. Endoscopic biopsy disclosed a neuroendocrine tumor histologically, therefore endoscopic mucosal resection was conducted. The tumor was effectively and evenly elevated after injection of a mixture of 0.2% hyaluronic acid and glycerol at a ratio of 1:1 into the submucosal layer. A small amount of indigo-carmine dye was also added for coloration of injection fluid. The lesion was completely resected en bloc with a snare after submucosal fluid injection. Immediately, muscle-fiber-like tissues were identified in the marginal area of the resected defect above the blue-colored layer, which suggested perforation. The defect was completely closed with a total of 9 endoclips, and no symptoms associated with peritonitis appeared thereafter. Histologically, the horizontal and vertical margins of the resected specimen were free of tumor and muscularis propria was also seen in the resected specimen. Generally, endoscopic mucosal resection is considered to be theoretically successful if the mucosal defect is colored blue. The blue layer in this case, however, had been created by unplanned injection into the subserosal rather than the submucosal layer.

Endoscopic full-thickness resection of a lateral spreading rectal tumor after unplanned injection of dilute hyaluronic acid into the subserosal layer (with video)

A 74-year-old woman underwent colonoscopy for investigation of a liver tumor. A lateral spreading tumor of the non-granular type (LST-NG), 25 mm in diameter, was detected at the rectosigmoid junction. As magnifying image-enhanced colonoscopy suggested a tubulovillous adenoma, endoscopic mucosal resection (EMR) was chosen for removal of the LST-NG. The lesion was effectively and evenly lifted after injection of 0.4% hyaluronic acid diluted with glycerol in the ratio of 1:1. A small amount of indigo-carmine dye was also added for coloration of the plane of resection. The lesion was completely removed en bloc. Although a blue-colored layer was identified in the resection defect, a small amount of a whitish layer was detected above the blue layer. The muscle layer was clearly located on the underside of the resected polyp. A total of 14 endoclips were used to close the defect completely. The patient was successfully treated conservatively without surgery. Histology of the resected specimen showed that it contained a tubulovillous adenoma with the submucosal layer and both layers of the muscularis propria. The surgical margin was free of neoplastic change horizontally and vertically. To the best of our knowledge, this is the first case report of full-thickness resection associated with EMR after unplanned injection of dilute hyaluronic acid into the subserosal layer rather than the intended submucosal layer. We describe how to promptly recognize this complication during colonoscopy, in order to achieve immediate closure of the defect, with the identification of a "mirror target sign" on the colonic wall.

Peeling a giant ileal lipoma with endoscopic unroofing and submucosal dissection

Lipoma is relatively common in the colon but is less often in the small intestine. Most lipomas are incidentally detected at endoscopy and are usually small and asymptomatic. However, some of them can present with obstruction and/or intussusceptions. Surgical resection is commonly recommended to remove such significant lipomas with a limited pedicle and larger than 2 cm in size, as endoscopic resection may result in unfavorable complications such as intestinal perforations. We report a case of 62-year-old man presenting with hematochezia. Colonoscopy showed a submucosal tumor, about 50 mm in size, in the terminal ileum. A clinical diagnosis of lipoma was established based on the findings of colonoscopy and abdominal computed tomography (CT). As the patient complained of hematochezia and mild iron deficiency anemia associated with repeated tumor prolapse, we decided to remove his lipoma. Consequently, the lesion was completely removed en bloc. Although abdominal CT immediately after removal of the lesion showed a small amount of free air, conservative treatment was successfully carried out for the perforation. Histologically, the removed lesion was a lipoma.

Efficacy of capillary pattern type IIIA/IIIB by magnifying narrow band imaging for estimating depth of invasion of early colorectal neoplasms

Background

Capillary patterns (CP) observed by magnifying Narrow Band Imaging (NBI) are useful for differentiating non-adenomatous from adenomatous colorectal polyps. However, there are few studies concerning the effectiveness of magnifying NBI for determining the depth of invasion in early colorectal neoplasms. We aimed to determine whether CP type IIIA/IIIB identified by magnifying NBI is effective for estimating the depth of invasion in early colorectal neoplasms.

Methods

A series of 127 consecutive patients with 130 colorectal lesions were evaluated from October 2005 to October 2007 at the National Cancer Center Hospital East, Chiba, Japan. Lesions were classified as CP type IIIA or type IIIB according to the NBI CP classification. Lesions were histopathologically evaluated. Inter and intraobserver variabilities were assessed by three colonoscopists experienced in NBI.

Results

There were 15 adenomas, 66 intramucosal cancers (pM) and 49 submucosal cancers (pSM): 16 pSM superficial (pSM1) and 33 pSM deep cancers (pSM2-3). Among lesions diagnosed as CP IIIA 86 out of 91 (94.5%) were adenomas, pM-ca, or pSM1; among lesions diagnosed as CP IIIB 28 out of 39 (72%) were pSM2-3. Sensitivity, specificity and diagnostic accuracy of the CP type III for differentiating pM-ca or pSM1 (<1000 μm) from pSM2-3 (≥1000 μm) were 84.8%, 88.7 % and 87.7%, respectively. Interobserver variability: κ = 0.68, 0.67, 0.72. Intraobserver agreement: κ = 0.79, 0.76, 0.75

Conclusion

Identification of CP type IIIA/IIIB by magnifying NBI is useful for estimating the depth of invasion of early colorectal neoplasms.

Transcutaneous monitoring of partial pressure of carbon dioxide during endoscopic submucosal dissection of early colorectal neoplasia with carbon dioxide insufflation: a prospective study

BACKGROUND

The authors have reported that carbon dioxide (CO(2)) insufflation is safe and effective for lengthy endoscopic submucosal dissection (ESD) with the patient under conscious sedation. However, CO(2) monitoring has not been assessed to clarify whether partial pressure of carbon dioxide (PCO(2)) increases during this type of long procedure. This study aimed to monitor CO(2) before, during, and after ESD to investigate whether CO(2) insufflation is safe for patients receiving a lengthy ESD of early colorectal neoplasia under conscious sedation.

METHODS

This study prospectively enrolled 35 consecutive patients who underwent ESD at the National Cancer Center Hospital. Transcutaneous PCO(2) (PtcCO(2)) was measured with a noninvasive sensor before, during, and after ESD for patients under conscious sedation using midazolam.

RESULTS

The mean size of removed lesions was 44 ± 22 mm (range, 15-100 mm). The operation time was 90 ± 100 min (range, 15-600 mm). The dose of midazolam was 5.7 ± 4.0 mg (range, 2-19 mg). The mean PtcCO(2) was 41 ± 5 mmHg (range, 33-53 mmHg) before ESD and 44 ± 6 mmHg (range, 32-54 mmHg) afterward. The mean peak PtcCO(2) during ESD was 55 ± 7 mmHg (range, 39-78 mmHg), which was significantly higher than before or after ESD (p < 0.0001). However, no complication associated with CO(2) insufflation such as CO(2) narcosis, gas embolism, or arrhythmia needing treatment was seen in any of the cases.

CONCLUSIONS

This study suggests that CO(2) insufflation is safe for patients receiving a lengthy colorectal ESD under conscious sedation.

A laterally-spreading tumor in a colonic interposition treated by endoscopic submucosal dissection

Herein we describe an early colonic carcinoma which developed in a colonic interposition 14 years after surgery for esophageal cancer, which was successfully treated by endoscopic submucosal dissection (ESD). An 80-year-old man underwent colonic interposition between the upper esophagus and stomach after surgery for an early esophageal squamous cell carcinoma in 1994. He received a surveillance endoscopy, and a laterally-spreading tumor of granular type, approximately 20 mm in size, was identified in the colonic interposition. An endoscopic biopsy revealed moderately differentiated adenocarcinoma histologically, however, we diagnosed the lesion as an intramucosal carcinoma based on the endoscopic findings. The lesion was safely and completely removed en bloc by ESD using a bipolar knife. Histologically, the lesion was an intramucosal moderately differentiated adenocarcinoma in a tubular adenoma.

Size does not determine the grade of malignancy of early invasive colorectal cancer

AIM: To clarify the clinicopathological characteristics of small and large early invasive colorectal cancers (EI-CRCs), and to determine whether malignancy grade depends on size.

METHODS: A total of 583 consecutive EI-CRCs treated by endoscopic mucosal resection or surgery at the National Cancer Center Hospital between 1980 and 2004 were enrolled in this study. Lesions were classified into two groups based on size: small (≤ 10 mm) and large (> 10 mm). Clinicopathological features, incidence of lymph node metastasis (LNM) and risk factors for LNM, such as depth of invasion, lymphovascular invasion (LVI) and poorly differentiated adenocarcinoma (PDA) were analyzed in all resected specimens.

RESULTS: There were 120 (21%) small and 463 (79%) large lesions. Histopathological analysis of the small lesion group revealed submucosal deep cancer (sm: ≥ 1000 &mgr;m) in 90 (75%) cases, LVI in 26 (22%) cases, and PDA in 12 (10%) cases. Similarly, the large lesion group exhibited submucosal deep cancer in 380 (82%) cases, LVI in 125 (27%) cases, and PDA in 79 (17%) cases. The rate of LNM was 11.2% and 12.1% in the small and large lesion groups, respectively.

CONCLUSION: Small EI-CRC demonstrated the same aggressiveness and malignant potential as large cancer.

Efficacy of the invasive/non-invasive pattern by magnifying chromoendoscopy to estimate the depth of invasion of early colorectal neoplasms

OBJECTIVE

During colonoscopy, estimation of the depth of invasion in early colorectal lesions is crucial for an adequate therapeutic management and for such task, magnifying chromoendoscopy (MCE) has been proposed as the best in vivo method. However, validation in large-scale studies is lacking. The aim of this prospective study was to clarify the effectiveness of MCE in the diagnosis of the depth of invasion of early colorectal neoplasms in a large series.

METHODS

A total of 4,215 neoplastic lesions were evaluated using MCE from October 1998 to September 2005 at the National Cancer Center Hospital, Tokyo, Japan. Lesions were prospectively classified according to the clinical classification of the pit pattern: invasive pattern or non-invasive pattern. All lesions were histopathologically evaluated.

RESULTS

There were 3,371 adenomas, 612 intramucosal cancers (m-ca), 232 submucosal cancers (sm-ca): 52 sm superficial (sm1) and 180 sm deep cancers (sm 2-3). Among lesions diagnosed as invasive pattern, 154 out of 178 (86.5%) were sm2-3, while among lesions diagnosed as non-invasive pattern, 4,011 out of 4,037 (99.4%) were adenomas, m-ca, or sm1. Sensitivity, specificity and diagnostic accuracy of the invasive pattern to differentiate m-ca or sm1 (< 1000 microm) from sm2-3 (> or = 1000 microm) were 85.6%, 99.4%, and 98.8%, respectively.

CONCLUSION

The determination of invasive or non-invasive pattern by MCE is a highly effective in vivo method to predict the depth of invasion of colorectal neoplasms.

Does autofluorescence imaging videoendoscopy system improve the colonoscopic polyp detection rate?--a pilot study

OBJECTIVES

Colonoscopy is considered the gold standard for the detection of colorectal polyps; however, polyps can be missed with conventional white light (WL) colonoscopy. The aim of this pilot study was to evaluate whether a newly developed autofluorescence imaging (AFI) system can detect more colorectal polyps than WL.

METHODS

A modified back-to-back colonoscopy using AFI and WL was conducted for 167 patients in the right-sided colon including cecum, ascending and transverse colon by a single experienced colonoscopist. The patient was randomized to undergo the first colonoscopy with either AFI or WL (group A: AFI-WL, group B: WL-AFI). The time needed for both insertion and examination for withdrawal and all lesions detected in the right-sided colon were recorded.

RESULTS

Eighty-three patients were randomized to group A and 84 to group B. The total number of polyps detected by AFI and WL colonoscopy was 100 and 73, respectively. The miss rate for all polyps with AFI (30%) was significantly less than that with WL (49%) (P= 0.01).

CONCLUSIONS

AFI detects more polyps in the right-sided colon compared to WL colonoscopy.

Staging of early colorectal cancers: magnifying colonoscopy versus endoscopic ultrasonography for estimation of depth of invasion

BACKGROUND AND AIMS

Preoperative estimation of depth of invasion in early colorectal cancers (CRCs) is essential for patient management. This study was conducted to compare the diagnostic accuracies of magnifying colonoscopy and endoscopic ultrasonography (EUS) for estimating the depth of invasion of early CRCs.

SUBJECTS AND METHODS

A total of 438 early CRCs were removed endoscopically or surgically from July 1993 through March 1999 at our hospital. Before removal, 102 lesions were evaluated with both magnifying colonoscopy and EUS and were included in this analysis. The diagnostic accuracy of each method, referring to the histology of the resected specimens, was evaluated.

RESULTS

The overall diagnostic accuracies were 87% (89/102) for magnifying colonoscopy and 75% (76/102) for EUS (P = 0.0985). Subgroup analysis was also done for polypoid and non-polypoid lesions. For polypoid lesions, the overall diagnostic accuracies of magnifying colonoscopy and EUS were 88% (60/68) and 72% (49/68), (P = 0.0785), and for non-polypoid lesions, they were 85% (29/34) and 79% (27/34), (P = 0.7169).

CONCLUSION

Although, there is a substantial difference in the overall diagnostic accuracies, it is not statistically significant. Therefore, we conclude that magnifying colonoscopy is at least as accurate as EUS for preoperative staging of early CRCs.

EMR using dextrose solution versus sodium hyaluronate for colorectal Paris type I and 0-II lesions: a randomized endoscopist-blinded study

BACKGROUND AND AIMS

Loss of mucosal 'lift' prior to submucosal dissection or endoscopic mucosal resection (EMR) increases the risk of complications. We conducted a randomized controlled trial comparing dextrose solution with sodium hyaluronic acid (SHA) for the EN BLOC resection of Paris type I/0-II and lateral spreading lesions of the colorectum.

PATIENTS AND METHODS

Patients with Paris type I/0-II or lateral spreading tumor lesions of < 30 mm were randomized in a 1 : 1 ratio to undergo EMR using either dextrose solution or SHA. The primary study outcome was complete resection. Secondary outcomes were endoscopic complications (i. e. perforation or bleeding) and polyp recurrence rates.

RESULTS

A total of 174 patients were randomized. R0 resection was achieved in 59 of the 82 lesions (72 %) in the dextrose group and 56 of the 81 lesions (69 %) in the SHA group ( P > 0.1), with no significant difference in median lesion diameter ( P > 0.1). The median number of post resection surveillance colonoscopies was 3 (range 2 - 7) in the dextrose group and 4 (range 2 - 6) in the SHA group ( P = NS). The median post index EMR resection follow-up period was 20 months (range 4 - 26) in the DS group and 18 months (range 3 - 22) in the SHA group ( P = NS). Recurrence rates were 1/82 (1.21 %) in the dextrose group and 1/81 (1.23 %) in the SHA group ( P = NS).

CONCLUSIONS

EMR using dextrose solution is as effective as SHA in terms of resection completion, recurrence rates, and complications.

A novel endoscopic suturing technique using a specially designed so-called "8-ring" in combination with resolution clips (with videos)

BACKGROUND

Although EMR has been proven to be a safe procedure, the risk of hemorrhage and perforation increases with the size of the resected lesion. To overcome such complications, we previously reported a technique using an endoloop and metal clips to close large mucosal defects after EMR. This procedure, however, requires a 2-channel colonoscope, which is not always available.

OBJECTIVES

Our purpose was to demonstrate the feasibility of mucosal defect closure by using a conventional single-channel colonoscope, a specially designed figure-of-8-shaped stainless steel ring (8-ring) and resolution clips.

DESIGN

Pilot study.

SETTING

Private outpatient clinic.

PATIENTS

A total of 10 patients with 10 lesions underwent this procedure for closure after EMR.

INTERVENTION

After EMR, a Resolution clip (Boston Scientific, Natick, Mass) was placed through 1 hole of the 8-ring and then attached to normal mucosa near 1 side of the resection site. Another resolution clip was inserted through the remaining hole of the device and clipped in the normal mucosa on the other side, thus providing complete closure. To strengthen the closure, conventional endoclips were also placed.

MAIN OUTCOME MEASUREMENTS

Technical feasibility of endoscopic closure of the mucosal defect after EMR and complications associated with endoscopic procedures.

RESULTS

Mean size of resected lesion was 16.3 mm. All the defects were successfully closed without any complication such as delayed bleeding or perforation.

LIMITATIONS

Further study is needed to examine the maximum size of defects that can be closed with this method.

CONCLUSIONS

Defects after EMR can be treated successfully with this simple technique.

Endoscopic treatment of large superficial colorectal tumors: a case series of 200 endoscopic submucosal dissections (with video)

BACKGROUND

Endoscopic submucosal dissection (ESD) is accepted as a minimally invasive treatment for early gastric cancer; however, it is not widely used in the colorectum because of its technical difficulty.

OBJECTIVE

To determine the feasibility of using ESD for treating large superficial colorectal tumors and to evaluate the clinical outcome.

DESIGN AND SETTING

Case series conducted at the National Cancer Center Hospital in Tokyo.

PATIENTS

A total of 198 consecutive patients were treated for 200 lesions.

INTERVENTIONS

Procedures were performed, before July 2004, by using a monopolar needle knife or an insulation-tipped knife (IT knife). After July 2004, the procedures were performed by using a bipolar needle knife or an IT knife. After injection of glycerol and sodium hyaluronate acid into the submucosal (sm) layer, a circumferential incision was made and sm dissection was performed endoscopically.

MAIN OUTCOME MEASUREMENTS

The en bloc resection rate was 84% and the curative resection rate was 83%.

RESULTS

Among the 200 ESDs, 51 involved tubular adenomas, 99 intramucosal cancers, 22 minute sm cancers, and 28 sm deep cancers. The median operation time was 90 minutes, and the mean size of resected specimens was 38 mm (range, 20-150 mm). Perforations occurred in 10 cases (5%) and postoperative bleeding in 4 cases (2%), but only 1 perforation case needed emergency surgery, because endoscopic clipping was ineffective.

LIMITATIONS

No long-term outcome data yet.

CONCLUSIONS

ESD is a feasible technique for treating large superficial colorectal tumors, because it provides a higher en bloc resection rate and is less invasive than surgical resection.

Iatrogenic perforation associated with therapeutic colonoscopy: a multicenter study in Japan

BACKGROUND AND AIM

Colonic perforation is the serious accidental complication. The aim of this study is to analyze the clinical presentation and management of recent iatrogenic perforations during therapeutic colonoscopy.

METHODS

Consecutive patients referred to four academic cancer centers in Japan were retrospectively reviewed using each center's endoscopy database of medical records. Data was obtained by means of an extensive data collection sheet. Since we evaluated the data including iatrogenic perforation during newly developed therapeutic procedure such as endoscopic submucosal dissection (ESD) or hemoclips, the collection of patient data was set from the period of the beginning of ESD technique in each hospital in this study.

RESULTS

The overall rate of occurrence of perforation was 0.15% (23/15, 160). Perforation rate for EMR (0.58%) showed a significantly higher rate (P < 0.0001) than that for hot biopsy and polypectomy. The rate for ESD (14%) showed a markedly higher rate (P < 0.0001) than that for other standard procedures. Of those perforations, endoscopic clipping was performed in 56.5% of the patients, and conservative treatment was successful in 100% of the patients with successful closure. Both CT scan findings and serology results (WBC, CRP) after perforation were poor predictors for need for surgery as opposed to conservative management.

CONCLUSIONS

Further improvements in EMR with special knife techniques are required to simply and safely remove large colorectal neoplasms, because perforation rate for ESD shows a markedly higher. Conservative management may be possible in patients who have undergone complete endoscopic clipping.

Determining the treatment strategy for colorectal neoplastic lesions: endoscopic assessment or the non-lifting sign for diagnosing invasion depth?

BACKGROUND AND STUDY AIMS

Assessment of the invasion depth of colorectal neoplasia is important in deciding between endoscopic and surgical resection treatment methods. Prior to attempting endoscopic resection, the lesion is lifted by submucosal injection, and a positive "non-lifting sign" is usually considered to indicate deeper submucosal infiltration. The purpose of this prospective multicenter study was to assess the predictive value of the non-lifting sign for differentiating between adenoma and early cancer (up to discrete submucosal infiltration [sm1]) and cancer with deeper infiltration (sm2).

PATIENTS AND METHODS

During an 11-month period, a total of 271 colorectal neoplastic lesions in 239 patients were included in the study. Apart from the location, size, and macroscopic type of the lesion, the presence or absence of the non-lifting sign was recorded and compared with the endoscopic assessment of invasion depth.

RESULTS

The non-lifting sign had a sensitivity of 61.5 %, a specificity of 98.4 %, a positive predictive value of 80.0 %, a negative predictive value of 96.0 %, and an accuracy of 94.8 %. Endoscopic diagnosis of deeper infiltration had a sensitivity of 84.6 %, a specificity of 98.8 %, a positive predictive value of 88.0 %, a negative predictive value of 98.4 %, and an accuracy of 97.4 %. Statistically significant differences were found in terms of sensitivity and accuracy.

CONCLUSION

Because of its lower sensitivity and accuracy, the non-lifting sign will not replace endoscopic assessment. If a lesion does not lift, this can make resection technically difficult, but does not reliably predict deeper cancerous invasion.