Laparoscopic Ventral Mesh Rectopexy (LVMR) for Internal and External Rectal Prolapse: An Analysis of 122 Consecutive Patients.

BACKGROUND: Even though several reports have been published on the results of laparoscopic ventral mesh rectopexy (LVMR) in Asia, there are few mid-term or long-term results of LVMR. The authors aimed to evaluate the results of LVMR in patients with internal rectal prolapse (IRP) external rectal prolapse (ERP). MATERIALS AND METHODS: From September 2013 to January 2019, 122 patients with IRP (n=48) or ERP (n=74) underwent LVMR. Constipation and fecal incontinence (FI) scores were evaluated using the Cleveland Clinic Florida score preoperatively and postoperatively. The questionnaire for the change of obstructed defecation or FI symptoms after surgery was also administered to grade the results as cured, improved, unchanged, or worsened for each survey. RESULTS: The mean age of the patients was 61.9 years. The mean operation time was 116.5 minutes, and the mean hospital stay was 5.1 days. The mean follow-up was 42.1 months. There were no mesh-related complications. Eight patients (10.7%) among the ERP group required additional surgery for recurrent full-thickness prolapse. Eleven patients (14.7%) who had mucosal prolapse within 2 cm underwent stapled hemorrhoidopexy after LVMR. In the postoperative 6-month period, the overall constipation score (7.12) significantly improved compared with the preoperative score (13.03) (P<0.001), whereas the FI score significantly improved after surgery (12.16 to 8.92; P<0.001). CONCLUSION: LVMR is a feasible and safe technique and favorable recurrence for ERP. Functional outcomes of obstructed defecation and FI were improved and the satisfaction of LVMR was high after the surgery. LVMR can be considered a recommended surgical option to treat ERP and IRP.

Nomogram Development and External Validation for Predicting the Risk of Lymph Node Metastasis in T1 Colorectal Cancer.

PURPOSE: Predicting lymph node metastasis (LNM) risk is crucial in determining further treatment strategies following endoscopic resection of T1 colorectal cancer (CRC). This study aimed to establish a new prediction model for the risk of LNM in T1 CRC patients. MATERIALS AND METHODS: The development set included 833 patients with T1 CRC who had undergone endoscopic (n=154) or surgical (n=679) resection at the National Cancer Center. The validation set included 722 T1 CRC patients who had undergone endoscopic (n=249) or surgical (n=473) resection at Daehang Hospital. A logistic regression model was used to construct the prediction model. To assess the performance of prediction model, discrimination was evaluated using the receiver operating characteristic (ROC) curves with area under the ROC curve (AUC), and calibration was assessed using the Hosmer-Lemeshow (HL) goodness-of-fit test. RESULTS: Five independent risk factors were determined in the multivariable model, including vascular invasion, high-grade histology, submucosal invasion, budding, and background adenoma. In final prediction model, the performance of the model was good that the AUC was 0.812 (95% confidence interval [CI], 0.770 to 0.855) and the HL chi-squared test statistic was 1.266 (p=0.737). In external validation, the performance was still good that the AUC was 0.771 (95% CI, 0.708 to 0.834) and the p-value of the HL chi-squared test was 0.040. We constructed the nomogram with the final prediction model. CONCLUSION: We presented an externally validated new prediction model for LNM risk in T1 CRC patients, guiding decision making in determining whether additional surgery is required after endoscopic resection of T1 CRC.

Clinical Characteristics and Incidence of Perianal Diseases in Patients With Ulcerative Colitis.

PURPOSE: While perianal disease (PAD) is a characteristic of patients with Crohn disease, it has been overlooked in patients with ulcerative colitis (UC). Thus, our study aimed to analyze the incidence and the clinical features of PAD in patients with UC. METHODS: We reviewed the data on 944 patients with an initial diagnosis of UC from October 2003 to October 2015. PAD was categorized as hemorrhoids, anal fissures, abscesses, and fistulae after anoscopic examination by experienced proctologists. Data on patients' demographics, incidence and types of PAD, medications, surgical therapies, and clinical course were analyzed. RESULTS: The median follow-up period was 58 months (range, 12-142 months). Of the 944 UC patients, the cumulative incidence rates of PAD were 8.1% and 16.0% at 5 and 10 years, respectively. The incidence rates of bleeding hemorrhoids, anal fissures, abscesses, and fistulae at 10 years were 6.7%, 5.3%, 2.6%, and 3.4%, respectively. The cumulative incidence rates of perianal sepsis (abscess or fistula) were 2.2% and 4.5% at 5 and 10 years, respectively. In the multivariate analyses, male sex (risk ratio [RR], 4.6; 95% confidence interval [CI], 1.7-12.5) and extensive disease (RR, 4.2; 95% CI, 1.6-10.9) were significantly associated with the development of perianal sepsis. CONCLUSION: Although the clinical course of PAD in patients with UC is not serious, in clinical practice, PAD is not rare in such patients. Therefore, careful examination and appropriate management for PAD is needed if the quality of life for patients with UC is to be improved.

Efficacy of topical 5-aminosalicylate monotherapy in patients with ulcerative proctitis with skip inflammation.

BACKGROUND AND AIM: In some patients with ulcerative proctitis (UP), skip inflammation is noted in the right side of the colon, but little is known about its clinical course. The aim of this study was to evaluate the clinical course of UP with skip inflammation and the efficacy of topical 5-aminosalicylate (5-ASA) monotherapy. METHODS: This study reviewed the data of 388 patients with an initial diagnosis of UP from January 2005 to October 2015. This study matched each UP patient with skip inflammation 1:2 with controls who had UP without skip inflammation; to reduce bias, this study matched the controls with the cases by age, gender, and initial disease activity. RESULTS: During the follow-up period (median: 69.5 months), the overall progression rates for the control group (n = 192) and the skip inflammation group (n = 96) were 24.0% and 32.9% at 10 years, respectively (log-rank P = 0.71). In the skip inflammation group, the progression rates were not significantly different between the 5-ASA combination group and the topical group, 33.4% and 26.6% at 10 years, respectively (log-rank P = 0.96). The overall acute exacerbation rates for the control and skip inflammation groups were 17.2% and 26.8% at 10 years, respectively (log-rank P = 0.68). In the skip inflammation group, the exacerbation rates were also not significantly different between the combination and topical treatment groups, 26.6% and 23.6% at 10 years, respectively (log-rank P = 0.88). CONCLUSION: The clinical course of UP with skip inflammation was not different from that of typical UP, and topical 5-ASA monotherapy for maintaining remission was as effective as 5-ASA combination therapy irrespective of the presence of skip lesions.

Composite intestinal adenoma-microcarcinoid in the colon and rectum: a case series and historical review.

BACKGROUND: Composite intestinal adenoma-microcarcinoid (CIAM) is a rare colorectal lesion that mostly comprises a conventional adenomatous component with a minute proportion of neuroendocrine (NE) component. Although microcarcinoids are well-recognized in the setting of chronic inflammatory disorders of the gastrointestinal tract, large intestinal microcarcinoids associated with intestinal adenoma are exceedingly rare and their clinicopathologic characteristics are yet to be elucidated. This study was performed to clarify their clinicopathologic characteristics and to review the relevant literature. METHODS: In total, 24 cases of CIAM in which tumors were excised endoscopically (n = 22) or surgically (n = 2) were retrieved from the Department of Pathology, Daehang Hospital. We analyzed their clinicopathologic characteristics and performed immunohistochemical staining for NE markers to determine their endocrine nature. RESULTS: CIAM usually developed in middle-aged and elderly patients, with a mean age of 62.0 years (range, 44-81 years). Thirteen patients were men and 11 were women, indicating a nearly equal sex ratio. Unlike classic carcinoid tumors, CIAMs occurred mostly in the colon (83.3% of cases), particularly in the proximal colon. Histologically, the microcarcinoid component consisted of low-grade NE cells arranged in small nests, glands or cords interspersed with glandular elements or less frequently resembled squamous morules. There was no expansile nodular or organoid growth pattern, which is typical of carcinoid tumors. The microcarcinoids were 1-20 mm in size (mean size, 4.7 mm) and were mostly situated in the basal lamina propria with no submucosal layer involvement; none showed desmoplastic reaction or increased proliferative activity. Follow-up data (mean, 23.1 months) were available for 18 patients; all patients are alive and well. CONCLUSIONS: To the best of our knowledge, ours is the largest series of patients with CIAM in the English-language literature. Microcarcinoids found in CIAMs appear to show favorable clinical outcomes regardless of their size, likely due to the absence of submucosal extension and/or increased proliferative activity. We recommend avoiding additional radical surgeries in patients who have endoscopically undergone complete CIAM excision unless they exhibit ominous histologic features such as submucosal extension or increased proliferative activity.

Comparative Evaluation of the Efficacy of Polyethylene Glycol With Ascorbic Acid and an Oral Sulfate Solution in a Split Method for Bowel Preparation: A Randomized, Multicenter Phase III Clinical Trial.

BACKGROUND: An adequate level of bowel preparation before colonoscopy is important. The ideal agent for bowel preparation should be effective and tolerable. OBJECTIVE: The purpose of this study was to compare the clinical efficacy and tolerability of polyethylene glycol with ascorbic acid and oral sulfate solution in a split method for bowel preparation. DESIGN: This was a prospective, multicenter, randomized controlled clinical trial. SETTINGS: Outpatients at the specialized clinics were included. PATIENTS: A total of 186 subjects were randomly assigned. After exclusions, 84 subjects in the polyethylene glycol with ascorbic acid group and 83 subjects in the oral sulfate solution group completed the study and were analyzed. INTERVENTIONS: Polyethylene glycol with ascorbic acid or oral sulfate solution in a split method was the included intervention. MAIN OUTCOME MEASURES: The primary end point was the rate of successful bowel preparation, which was defined as being excellent or good on the Aronchick scale. Tolerability and adverse events were also measured. RESULTS: Success of bowel preparation was not different between 2 groups (91.7% vs 96.4%; p = 0.20), and the rate of adverse GI events (abdominal distension, pain, nausea, vomiting, or abdominal discomfort) was not significantly different between the 2 groups. In contrast, the mean intensity of vomiting was higher in the oral sulfate solution group than in the polyethylene glycol with ascorbic acid group (1.6 ± 0.9 vs 1.9 ± 1.1; p = 0.02). LIMITATIONS: All of the colonoscopies were performed in the morning, and the subjects were offered enhanced instructions for bowel preparation. In addition, the results of tolerability and adverse effect may have a type II error, because the number of cases was calculated for confirming the efficacy of bowel preparation. CONCLUSIONS: Oral sulfate solution is effective at colonoscopy cleansing and has acceptable tolerability when it is compared with polyethylene glycol with ascorbic acid. The taste and flavor of oral sulfate solution still need to be improved to enhance tolerability.

Persistent Bleeding Following a Stapled Hemorrhoidopexy.

A stapled hemorrhoidopexy (SH) is widely used for treatment of patients with grades III and IV hemorrhoids. The SH is easy to perform, is associated with less pain and allows early return to normal activities. However, complications, whether severe or not, have been reported. Here, we present the case of a female patient with persistent bleeding after a SH. The bleeding was caused by the formation of granulation tissue at the stapler line, diagnosed with sigmoidoscopy, and successfully treated via transanal excision (TAE) under spinal anesthesia. The biopsy showed inflammatory granulation tissue. After the TAE, her symptom was completely gone.

Reappraisal of hMLH1 promoter methylation and protein expression status in the serrated neoplasia pathway.

AIMS: The aim of this study was to determine whether human mutL homologue 1 (hMLH1) inactivation precedes the progression of sessile serrated lesion (SSL) into SSL with cytological dysplasia (SSL/D) and to define the histological stage at which promoter methylation and inactivation of hMLH1 occur. METHODS AND RESULTS: Using the MassARRAY EpiTYPER assay and immunohistochemistry, we examined methylation levels and the protein expression status of hMLH1 in 33 SSL/Ds with conventional epithelial dysplasia and compared the results with those of control hyperplastic polyps (HPs) and SSLs. The methylation level of hMLH1 was higher in the dysplastic component than in the non-dysplastic component of SSL/Ds (P = 0.005), and differed significantly with regard to the degree of dysplasia (P = 0.002). The methylation levels of hMLH1 in the dysplastic component of SSL/Ds tended to be higher than those of control SSLs and HPs (P = 0.063 and P = 0.017, respectively). The loss of hMLH1 protein expression was identified in only 13 of 33 (39.39%) dysplastic components of SSL/Ds. CONCLUSION: Promoter methylation and loss of protein expression of hMLH1 are not parallel processes that occur concurrently. hMLH1 methylation is an early molecular event which occurs even in HP. However, the loss of hMLH1 expression is a much later step, found in approximately 40% of SSL/Ds at various histological stages. Notably, the loss of hMLH1 protein expression does not necessarily precede the development of cytological dysplasia in SSL.

Clinical Features of Tuberculous Versus Crohn's Anal Fistulas, in Korea.

BACKGROUND AND AIMS: In Western countries, tuberculous anal fistula may not be an issue because tuberculosis [TB] is not common, and this is a very rare form of extrapulmonary manifestation of TB. However in TB-endemic countries, careful diagnostic differentiation is required because the clinical features of TB anal fistula and Crohn's disease [CD] anal fistula are similar, with distinguishing features remaining unclear. We aimed to analyse the clinical features of TB versus CD anal fistulas. METHOD: Among 13872 patients who underwent anal fistula surgery from 2003 to 2014, 87 patients with TB fistulas and 116 patients with CD fistulas were included. Data on the annual incidence of TB and CD, as well as the clinical, pathological, ultrasonographic, colonoscopic and surgical data were analysed. RESULTS: Compared with CD, the TB group was older [median: 37 vs 22 years] and underlying chronic illness was more common [20.3% vs 2.6%]. In the TB group, 46 patients [59.7%] showed active or inactive pulmonary TB, and acid-fast bacilli and caseating granuloma were found in 56.3% and 62.1%, respectively. During colonoscopy, mucosal lesions were observed more frequently in CD [96.9% vs 16.9%]. CONCLUSIONS: TB anal fistula is clinically very similar to CD anal fistula. In Korea, the incidence of CD anal fistula has recently increased in prevalence, whereas the prevalence of TB anal fistula is decreasing but is still persistent. We recommend that clinicians should prepare for a possibility of TB as well as CD anal fistula in TB-endemic countries including Korea.

Sessile serrated adenoma/polyps with a depressed surface: a rare form of sessile serrated adenoma/polyp.

Sessile serrated adenoma/polyps (SSA/Ps) usually appear flat to sessile with a smooth-appearing surface. However, macroscopic appearances of SSA/P can vary from flat-elevated to nodular and can even show a pedunculated configuration as we previously reported. The aim of the current study was to evaluate the clinicopathologic features of another under-recognized form of SSA/P which shows a depressed surface. Among 634 cases of sessile serrated adenoma/polyp, a total of seven sessile serrated adenoma/polyps showing a depressed surface were identified in 6 patients during the review of endoscopic images between January 2013 and November 2013. One of these was found during the review of previous endoscopic images of the same patient. Patients were more often middle-aged to elderly men (83.3%) and had synchronous conventional adenomas and/or SSA/Ps except for one man. The polyps usually occurred in the proximal colon (71.4%) and the mean size of polyps was 9.3 mm (range; 6-13 mm). Most cases (71.4%) were of a flat-elevated type, and the remaining polyps (28.6%) were sessile. The majority of polyps (85.7%) showed a mucus cap. All but one of the cases (85.7%) showed BRAF-V600E mutations. Our findings are that SSA/Ps can show a central depression although such cases are rare. The endoscopic and clinicopathologic features of SSA/Ps showing a depressed surface appear to be similar to usual SSA/Ps except for the presence of a depressed surface and marked male preponderance. Virtual slides: The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1562070886167874 .

The significance of ectopic crypt formation in the differential diagnosis of colorectal polyps.

BACKGROUND: Ectopic crypts, defined as abnormally positioned crypts that have lost their orientation toward the muscularis mucosae, have been suggested to be the best defining histologic feature of traditional serrated adenoma (TSA). However, the significance of ectopic crypt formation (ECF) in the distinction between TSA and conventional adenoma (CA) has rarely been studied. METHODS: We designed this study to determine if ECF can be found in CA and its presence is exclusive to TSA. We studied 107 TSAs and 191 CAs including 106 tubular adenomas (TAs), 66 tubulovillous adenomas (TVAs), and 19 villous adenomas (VAs). RESULTS: ECF was identified in most (79.4%) but not all TSAs. Additionally, ECF was not infrequent in CA (62 of 191, 32.5%), and its presence correlated with the presence of a villous component and larger tumor size (each p <0.001). CONCLUSIONS: Based on its strong association with the presence of a villous component and larger tumor size, ECF appears to be involved in the protuberant growth of colorectal CA. Because ECF can be found in CA, particularly in cases with a villous component, the possibility of CA should be considered before making a diagnosis of TSA when encountering colorectal polyps with ECF. VIRTUAL SLIDES: The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/13000_2014_212.

Traditional serrated adenoma of the colorectum: clinicopathologic implications and endoscopic findings of the precursor lesions.

OBJECTIVES: To investigate the clinicopathologic and endoscopic features of precursor lesions associated with traditional serrated adenomas (TSAs). METHODS: Mutation studies for BRAF, KRAS, PIK3CA, and EGFR and immunohistochemical staining for Ki-67 were performed on 107 TSAs from 104 patients. RESULTS: Nondysplastic hyperplastic polyp (HP) or sessile serrated adenoma/polyp (SSA/P) precursor lesions were found in 56 (52.3%) TSAs, among which 32 (57.1%) cases showed a flat-elevated lesion with a type II pit pattern during endoscopy. TSAs with an SSA/P precursor lesion were usually found in the proximal colon, while TSAs with an HP or with no precursor lesion were mainly located in the distal colon and rectum (P < .001). TSAs with a precursor lesion showed a lower frequency of conventional epithelial dysplasia and KRAS mutation as well as a higher frequency of BRAF mutation compared with those with no precursor lesion (P = .002, P < .001, and P < .001, respectively). CONCLUSIONS: A significant proportion of HP or SSA/P precursor lesions accompanied by TSAs can be detected by endoscopy based on both their flat-elevated growth and type II pit patterns. The heterogeneity of TSAs in terms of clinicopathologic and molecular features correlated with the status or type of precursor lesions.

Pedunculated serrated polyp with histologic features of sessile serrated adenoma: a clinicopathologic and molecular study.

In this study, we describe a previously undescribed pedunculated serrated polyp of the colon showing typical features of sessile serrated adenoma/polyp (SSA/P). All polyps were pedunculated, located in the proximal colon, small in size, and occurred in elderly patients. Histologically, the polyps showed typical features of SSA/P in the basal crypts with irregular, asymmetric expression of Ki-67. All polyps showed the BRAF-V600E mutation. The cells in the polyps did not show obvious cytologic dysplasia, prominent serration, or diffuse cytoplasmic eosinophilia with any occurrence of the so-called "ectopic crypt formation." We consider pedunculated serrated polyp showing features of SSA/P as a previously undescribed form of serrated adenoma/polyp in the spectrum of serrated neoplasia, which might represent a pedunculated variant of SSA/P or a precursor lesion of proximally located traditional serrated adenomas in the earliest stage.

Can endoscopic submucosal dissection technique be an alternative treatment option for a difficult giant (≥ 30 mm) pedunculated colorectal polyp?

BACKGROUND: Snare polypectomy of a giant pedunculated colorectal polyp is sometimes technically demanding, and, therefore, piecemeal resection is inevitable, despite the relative risk of invasive cancer and postpolypectomy bleeding. OBJECTIVE: The aim of this study was to evaluate the efficacy and safety of endoscopic submucosal dissection in comparison with conventional snare polypectomy for giant pedunculated polyps DESIGN AND SETTINGS: We retrospectively reviewed the clinical outcomes and complications of endoscopic polypectomy for giant pedunculated polyps from October 2006 to November 2011. PATIENTS: All the patients who underwent endoscopic submucosal dissection (n = 23) or snare polypectomy (n = 20) for pedunculated polyps ≥ 3 cm were enrolled consecutively. In the case of a giant pedunculated polyp with 1) poor visualization of the stalk, 2) technical difficulties in snare positioning for en bloc resection, or 3) need for trimming of the head, we did not attempt piecemeal snare polypectomy, and we performed endoscopic submucosal dissection instead. (These were arbitrarily defined as "difficult" giant pedunculated polyps.) MAIN OUTCOME MEASURES: Data on the patient's demography, endoscopic and histopathologic findings, clinical outcomes, and complications were analyzed. RESULTS: Among the 43 giant pedunculated polyps, 23 polyps were defined as "difficult" polyps and were removed with endoscopic submucosal dissection. Subpedunculated (stalk <1 cm) type was more common in the "difficult" polyp group (p = 0.01). The overall incidence of cancer was 18.6% (8/43). En bloc resection rates were 100% (23/23) in the endoscopic submucosal dissection group and 90% (18/20) in the snare polypectomy group. The procedure times of snare polypectomy and endoscopic submucosal dissection group did not differ significantly (41.7 ± 13.7 minutes vs 44.9 ± 35.6 minutes, p = 0.70). Postpolypectomy bleeding was noted in 1 case (4.3%) in the endoscopic submucosal dissection group and in 3 cases (15%) in the snare polypectomy group. CONCLUSIONS: Endoscopic submucosal dissection, as well as the snare polypectomy for giant pedunculated polyps, appeared to be effective without major complications and can be an alternative option to achieve en bloc resection, particularly for difficult cases, such as giant subpedunculated polyps.

Endoscopic submucosal dissection for colorectal tumors--1,000 colorectal ESD cases: one specialized institute's experiences.

PURPOSE: Endoscopic submucosal dissection (ESD) is a very useful endoscopic technique, making it possible to perform en bloc resection regardless of lesion size. Since the introduction of ESD at our hospital, we have performed 1,000 colorectal ESDs during 56 months. The purpose of this study was to evaluate the clinical outcomes of our colorectal ESD experience and to access the efficacy and safety of colorectal ESD. METHODS: Between October 2006 and August 2011, we performed ESD on 1,000 consecutive colorectal tumors in 966 patients. We evaluated the clinical outcomes of all said cases. RESULTS: The mean resected tumor size was 24.1 ± 13.3 (3-145) mm. Our overall endoscopic en bloc resection rate was 97.5% (975/1,000), and our R0 resection rate was 91.2% (912/1,000) respectively. Our perforation rate was 5.3% (53/1,000). Of these 53 perforations, 50 cases were treated through conservative management with/without endoscopic clipping, whereas the remaining 3 patients received laparoscopic operation. Pathological examination showed adenocarcinoma in 37.2% of cases (372/1,000) and neuroendocrine tumors in 11.2% (112/1,000). We recommended additional radical surgery to 82 patients who had a risk of lymph node metastasis. Follow-up colonoscopies were performed on 722 patients. During the median follow-up period of 13 (1-62) months, there were three recurrences (0.4%). CONCLUSIONS: ESD is technically difficult, with a substantial risk of perforation. However, ESD enabled en bloc resection and pathologically complete resection of large colorectal epithelial tumors and submucosal tumors. As experience with the technique increases, ESD may gradually replace piecemeal endoscopic mucosal resection and radical colon resection in the treatment of colorectal tumors.

Regression of giant pseudopolyps in inflammatory bowel disease.

Inflammatory pseudopolyps are formed in the regenerative and healing phases of ulcerated epithelium. Giant pseudopolyposis of the colon (pseudopolyp larger than 1.5 cm in size) is a very rare complication of inflammatory bowel disease and it may lead to colonic intussusception or luminal obstruction, but the more important clinical significance is that it can be endoscopically confused with a malignancy, although it is generally regarded as having no malignant potential. It has been reported that giant pseudopolyposis of the colon rarely regresses with medical management alone and this sometimes require surgical or endoscopic resection. This report illustrates 2 unusual cases of giant pseudopolyps associated with Crohn's disease and ulcerative colitis, and these giant pseudopolyps were initially confused with villous adenoma or adenocarcinoma, but they showed regression after adequate medical therapy.

Clinical risk factors for perforation during endoscopic submucosal dissection (ESD) for large-sized, nonpedunculated colorectal tumors.

BACKGROUND: The possible risk of colonic perforation during endoscopic submucosal dissection (ESD) for colorectal tumors is a barrier to wide application. This retrospective study was performed to evaluate the risk and the predictive factors for perforation during ESD procedure. METHODS: Between October 2006 and November 2010, a total of 499 consecutive patients (mean age 60.0 ± 11.3 years) who underwent ESD for large-sized (≥ 20 mm), nonpedunculated colorectal tumor were analyzed. First, incidence rate and clinical course of perforation were evaluated. Second, patient-related variables (age, sex, history of aspirin or antiplatelet agents, and comorbidity), endoscopic variables (tumor size, location, and type), procedure-related variables (experience of procedures, procedure time, and materials of submucosal injection), and pathologic diagnosis were analyzed. RESULTS: The mean size of the lesions was 28.9 mm. The overall en bloc resection rate was 95.0%. Perforation occurred in 37 out of 499 patients (7.4%). Thirty-four patients could be successfully treated conservatively. The type (laterally spreading tumor) and the location (right-sided colon) of the tumors, less experience of the procedure (<100 cases) in each endoscopist, and submucosal injection without hyaluronic acid were associated with higher frequency of perforation (all P < 0.05). On multivariate analysis, laterally spreading type of tumor [odds ratio (OR) 4.10, 95% confidence interval (CI) 1.17-14.34] and submucosal injection with hyaluronic acid (OR 0.31, 95% CI 0.13-0.72) were independent predictive factors. CONCLUSIONS: Perforation rate was 7.4%, and most cases could be successfully managed nonsurgically. In case of laterally spreading type of tumor, more caution is needed during submucosal dissection and long-lasting submucosal cushion is important for preventing perforation.

A case of Crohn's disease with improvement after azathioprine-induced pancytopenia.

The immunosuppressant azathioprine (AZA) is widely used in the treatment of inflammatory bowel disease (IBD) for both inducing and maintaining remission. However, the adverse effects of AZA can often necessitate a dose reduction or discontinuation. Bone marrow suppression is one of the most serious complications with AZA treatment. On the other hand, some reports have suggested that neutropenia during AZA therapy reduced the relapse rates of IBD patients, and there have been some cases where eradication of the sensitized leukocytes by leukapheresis or bone marrow transplantation improved the IBD, which may explain the relevant role of neutropenia in controlling disease activity. This report describes the case of a 22-year-old male patient who had Crohn's colitis and complicated perianal fistulas that required immunosuppression; he achieved endoscopically determined remission and showed accelerated mucosal healing as well as clinical remission following the AZA-induced pancytopenia.