Intestinal ultrasound for intestinal Behçet disease reflects endoscopic activity and histopathological findings.

Background/Aims: Intestinal Behçet disease is typically associated with ileocecal punched-out ulcers and significant morbidity and mortality. Intestinal ultrasound is a noninvasive imaging technique for disease monitoring. However, no previous reports have compared intestinal ultrasound with endoscopic ulcer activity or histopathological findings for intestinal Behçet disease. We evaluated the usefulness of intestinal ultrasound for assessing the activity of ileocecal ulcers in intestinal Behçet disease. Methods: We retrospectively compared intestinal ultrasound findings with 73 corresponding endoscopic images and 6 resected specimens. The intestinal ultrasound findings were assessed for 7 parameters (bowel wall thickness, vascularity [evaluated using the modified Limberg score with color Doppler], bowel wall stratification, white-plaque sign [strong hyperechogenic lines or spots], mesenteric lymphadenopathy, extramural phlegmons, and fistulas), and endoscopic ulcer activity was classified into active, healing, and scar stages. Histopathological findings were evaluated by consensus among experienced pathologists. Results: Bowel wall thickness (P< 0.001), vascularity (P< 0.001), loss of bowel wall stratification (P= 0.015), and white-plague sign (P= 0.013) were significantly exacerbated in the endoscopic active ulcer stage. Receiver operating characteristic curve analysis revealed that a bowel wall thickness of > 5.5 mm (sensitivity 89.7%, specificity 85.3%) was potentially useful for detecting active lesions. When compared with histopathological findings, an increase in bowel wall thickness reflected the ulcer marginal ridge, and the white-plaque sign reflected the ulcer bottom. Conclusions: Intestinal ultrasound is useful for monitoring intestinal ulcer activity in intestinal Behçet disease.

Histological differentiation between sporadic and colitis-associated intestinal cancer in a nationwide study: A propensity-score-matched analysis.

BACKGROUND AND AIM: Colitis-associated intestinal cancer (CAC) can develop in patients with inflammatory bowel disease; however, the malignant grade of CAC may differ from that of sporadic colorectal cancer (CRC). Therefore, we compared histological findings distinct from cancer stage between CAC and sporadic CRC to evaluate the features of CAC. METHODS: We reviewed the clinical and histological data collected from a nationwide database in Japan between 1983 and 2020. Patient characteristics were compared to distinguish ulcerative colitis (UC), Crohn's disease (CD), and sporadic CRC. Comparisons were performed by using all collected data and propensity score-matched data. RESULTS: A total of 1077 patients with UC-CAC, 297 with CD-CAC, and 136 927 with sporadic CRC were included. Although the prevalence of well or moderately differentiated adenocarcinoma (Tub1 and Tub2) decreased according to tumor progression for all diseases (P < 0.01), the prevalence of other histological findings, including signet ring cell carcinoma, mucinous carcinoma, poorly differentiated adenocarcinoma, or squamous cell carcinoma, was significantly higher in CAC than in sporadic CRC. Based on propensity score-matched data for 982 patients with UC and 268 with CD, the prevalence of histological findings other than Tub1 and Tub2 was also significantly higher in those with CAC. At pT4, mucinous carcinoma occurred at a significantly higher rate in patients with CD (45/86 [52.3%]) than in those with sporadic CRC (13/88 [14.8%]) (P < 0.01). CONCLUSION: CAC, including early-stage CAC, has a higher malignant grade than sporadic CRC, and this difference increases in significance with tumor progression.

Crohn's Disease-Associated Anorectal Cancer Has a Poor Prognosis With High Local Recurrence: A Subanalysis of the Nationwide Japanese Study.

INTRODUCTION: Colorectal cancer (CRC) is one of the major life-threatening complications in patients with Crohn's disease (CD). Previous studies of CD-associated CRC (CD-CRC) have involved only small numbers of patients, and no large series have been reported from Asia. The aim of this study was to clarify the prognosis and clinicopathological features of CD-CRC compared with sporadic CRC. METHODS: A large nationwide database was used to identify patients with CD-CRC (n = 233) and sporadic CRC (n = 129,783) over a 40-year period, from 1980 to 2020. Five-year overall survival (OS), recurrence-free survival (RFS), and clinicopathological characteristics were investigated. The prognosis of CD-CRC was further evaluated in groups divided by colon cancer and anorectal cancer (RC). Multivariable Cox regression analysis was used to adjust for confounding by unbalanced covariables. RESULTS: Compared with sporadic cases, patients with CD-CRC were younger; more often had RC, multiple lesions, and mucinous adenocarcinoma; and had lower R0 resection rates. Five-year OS was worse for CD-CRC than for sporadic CRC (53.99% vs 71.17%, P < 0.001). Multivariable Cox regression analysis revealed that CD was associated with significantly poorer survival (hazard ratio 2.36, 95% confidence interval: 1.54-3.62, P < 0.0001). Evaluation by tumor location showed significantly worse 5-year OS and RFS of CD-RC compared with sporadic RC. Recurrence was identified in 39.57% of CD-RC cases and was mostly local. DISCUSSION: Poor prognosis of CD-CRC is attributable primarily to RC and high local recurrence. Local control is indispensable to improving prognosis.

Impact of the body mass index on the retention of the anorectal mucosa after double-stapled ileal pouch-anal anastomosis for ulcerative colitis.

BACKGROUND: Double-stapled ileal pouch-anal anastomosis (DS-IPAA) is easy to construct and has a good functional outcome in patients with ulcerative colitis (UC). However, retention of the anorectal mucosa may lead to a subsequent risk of inflammation and neoplasia. This study aimed to identify factors associated with the retention of a large amount of anorectal mucosa after DS-IPAA. METHODS: The medical records of 163 patients who had undergone one-stage total proctocolectomy and DS-IPAA for UC between 2007 and 2020 were retrospectively reviewed. The patients were divided into two groups according to the length of the retained mucosa. The high anastomosis group was defined as having a retained mucosal length of ≥ 30 mm in the anterior or posterior wall. Clinical factors were compared between the high and low anastomosis groups. RESULTS: The high anastomosis group showed a significantly higher body mass index (BMI) (high vs. low: 23.2 vs. 19.0), longer operation time (304 vs. 263) and greater blood loss (357 vs. 240). In the multivariate analysis, high BMI was the only factor significantly associated with high anastomosis (odds ratio 1.32). There was a positive correlation between BMI and the length of the retained mucosa. CONCLUSIONS: In DS-IPAA, BMI showed the strongest association with the retention of a large amount of the anorectal mucosa. In high BMI patients, although the risk of inability of anastomosis is little than that of IPAA with mucosectomy, the possible retention of a large amount of mucosa should be considered.

Serrated polyps in patients with ulcerative colitis: Unique clinicopathological and biological characteristics.

BACKGROUND: Serrated polyps have recently been reported in patients with ulcerative colitis (UC); however, their prevalence and detailed characteristics remain unclear. METHODS: The prevalence and clinicopathological and biological characteristics of serrated polyps in patients with UC were retrospectively examined in a single tertiary inflammatory bowel disease center in Japan from 2000 to 2020. RESULTS: Among 2035 patients with UC who underwent total colonoscopy, 252 neoplasms, including 36 serrated polyps (26 in colitis-affected segments, 10 in colitis-unaffected segments), were identified in 187 patients with UC. The proportion of serrated polyps was 1.8% (36/2035). Serrated polyps in colitis-affected segments were common with extensive colitis (88%), history of persistent active colitis (58%), and long UC duration (12.1 years). Serrated polyps in colitis-affected segments were more common in men (88%). Of the 26 serrated polyps in colitis-affected segments, 15, 6, and 5 were categorized as sessile serrated lesion-like dysplasia, traditional serrated adenoma-like dysplasia, and serrated dysplasia not otherwise specified, respectively. Sessile serrated lesion-like dysplasia was common in the proximal colon (67%) and with BRAF mutation (62%), whereas traditional serrated adenoma-like dysplasia and serrated dysplasia not otherwise specified were common in the distal colon (100% and 80%, respectively) and with KRAS mutations (100% and 75%, respectively). CONCLUSIONS: Serrated polyps comprised 14% of the neoplasias in patients with UC. Serrated polyps in colitis-affected segments were common in men with extensive and longstanding colitis, suggesting chronic inflammation in the development of serrated polyps in patients with UC.

Curable leakage in stapled IPAA has little effect on the long-term pouch function.

PURPOSE: This study aimed to evaluate the frequency and grade of anastomotic leakage (AL) in stapled ileal pouch-anal anastomosis (IPAA) and its long-term impact on the pouch functions. METHODS: A longitudinal cohort study was conducted on UC patients who underwent stapled IPAA at Yokohama City University Medical Center between 2007 and 2018. The diagnosis and grading of AL were performed in accordance with the recommendations of the International Study Group of Rectal Cancer. We assessed the functional pouch rate, late complication, pouch survival rate, bowel function (bowel movements per day, soiling, spotting, difficulty in distinguishing feces from flatus) and pouch inflammation (pouchitis disease activity index; PDAI) in the long-term period. RESULTS: Two hundred seventy-six patients were analyzed. Twenty-three (8.3%; grade B/C; 13/10) patients were diagnosed with AL, but a functional pouch was achieved in all the twenty-three patients. Anastomotic stricture was significantly more common in patients with AL (AL group) than in patients without AL (non-AL group; AL/non-AL: 13.0/3.2%, p = 0.020). There were no differences in other late complications. Furthermore, the pouch survival rate did not differ between the AL and non-AL groups (100.0/97.9%/10 years, p = 0.494). There were no differences between the groups in bowel movements per day, spotting, soling, difficulty in distinguishing feces from flatus, or PDAI postoperatively. CONCLUSIONS: Curable AL may not affect late complications (except anastomotic stricture), pouch survival, the bowel function, or pouch inflammation over the long term. Perioperative management to prevent the severity of AL is as important as preventing its occurrence.

Appropriate Preconception Corticosteroid-Free Remission Period in Pregnant Women With Ulcerative Colitis.

BACKGROUND: In women with inflammatory bowel disease, at least 3 months of preconception corticosteroid-free remission (CFREM) is recommended by experts in current consensus statements. However, data are lacking on the appropriate preconception remission period. We investigated the appropriate preconception CFREM period in women with ulcerative colitis to reduce maternal disease activity and adverse pregnancy outcomes (ie, preterm birth, low birth weight, and small for gestational age). METHODS: We retrospectively examined 141 pregnancies in women with ulcerative colitis at 2 institutions. We categorized the patients into 3 subgroups by their preconception CFREM period (≥3 months, >0 to <3 months, and non-CFREM). We also investigated disease activity during pregnancy and postpartum and adverse pregnancy outcomes in each group. RESULTS: During pregnancy, the rate of active disease was significantly lower in the ≥3 months and >0 to <3 months CFREM groups compared with that in the non-CFREM group (P < .001 and P = .0257, respectively). Postpartum, the rate of active disease was significantly lower in the ≥3 months CFREM group compared with that in the non-CFREM group (P = .0087). The preconception CFREM period of ≥3 months was an independent inhibitory factor for active disease during pregnancy and postpartum (adjusted odds ratio, 0.15; P = .0035; and adjusted odds ratio, 0.33; P = .027, respectively). Adverse pregnancy outcomes were less common in the >3 months CFREM group compared with those in the other groups, but this difference was not significant. CONCLUSIONS: A preconception CFREM period of more than 3 months may be appropriate for better maternal and adverse pregnancy outcomes, as recommended in consensus statements.

In women with ulcerative colitis, a preconception corticosteroid-free remission period for at least 3 months may be appropriate. This period could reduce disease activity during pregnancy and postpartum and reduce the incidence of adverse pregnancy outcomes.

Effect of Biologics on the Risk of Advanced-Stage Inflammatory Bowel Disease-Associated Intestinal Cancer: A Nationwide Study.

INTRODUCTION: The aim of this study was to evaluate the effect of biologics on the risk of advanced-stage inflammatory bowel disease (IBD)-associated intestinal cancer from a nationwide multicenter data set. METHODS: The medical records of patients with Crohn's disease (CD) and ulcerative colitis (UC) diagnosed with IBD-associated intestinal neoplasia (dysplasia or cancer) from 1983 to 2020 were included in this study. Therapeutic agents were classified into 3 types: biologics, 5-aminosalicylic acid, and immunomodulators. The pathological cancer stage was compared based on the drug used in both patients with CD and UC. RESULTS: In total, 1,042 patients (214 CD and 828 UC patients) were included. None of the drugs were significantly associated with cancer stage in the patients with CD. In the patients with UC, an advanced cancer stage was significantly associated with less use of biologics (early stage: 7.7% vs advanced stage: 2.0%, P < 0.001), 5-aminosalicylic acid, and immunomodulators. Biologic use was associated with a lower incidence of advanced-stage cancer in patients diagnosed by regular surveillance (biologics [-] 24.5% vs [+] 9.1%, P = 0.043), but this was not the case for the other drugs. Multivariate analysis showed that biologic use was significantly associated with a lower risk of advanced-stage disease (odds ratio = 0.111 [95% confidence interval, 0.034-0.356], P < 0.001). DISCUSSION: Biologic use was associated with a lower risk of advanced IBD-associated cancer in patients with UC but not with CD. The mechanism of cancer progression between UC and CD may be different and needs to be further investigated.

Fulminant Amebic Enteritis in the Perinatal Period.

Pregnancy is a known risk factor for amebic enteritis, which develops into potentially fatal fulminant amebic enteritis in some cases. We describe a case of a 27-year-old non-immunosuppressed pregnant woman with fulminant amebic enteritis complicated with cytomegalovirus enteritis. She improved with intensive care and intravenous metronidazole and ganciclovir but eventually required subtotal colectomy for intestinal stenosis. It is difficult to diagnose amebic enteritis, especially in a non-endemic area. Amebic enteritis must be considered as a differential diagnosis for refractory diarrhea with bloody stools in women in the perinatal period, even those without immunosuppression.

Clinical features and oncological outcomes of intestinal cancers associated with ulcerative colitis and Crohn's disease.

BACKGROUND: Patients with longstanding inflammatory bowel disease are at high risk of developing intestinal cancers. In this study, we aimed to elucidate the differences between intestinal cancers associated with ulcerative colitis and Crohn's disease. METHODS: Intestinal cancers in ulcerative colitis and Crohn's disease patients treated between 1983 and 2020 at 43 Japanese institutions were retrospectively analyzed.. RESULTS: A total of 1505 intestinal cancers in 1189 ulcerative colitis and 316 Crohn's disease patients were studied. Almost all of ulcerative colitis-associated cancers (99%) were in the colon and rectum, whereas half of Crohn's disease-associated cancers (44%) were in the anus, with 11% in the small intestine. Ulcerative colitis-associated cancers were diagnosed more frequently by surveillance (67% vs. 25%, P < 0.0001) and at earlier stages (stages 0-1, 71% vs. 27%, P < 0.0001) compared with Crohn's disease-associated cancers. Colorectal cancers associated with Crohn's disease showed a significantly worse 5-year overall survival rate than those associated with ulcerative colitis (stage 2, 76% vs. 89%, P = 0.01, stage 3, 18% vs. 68%, P = 0.0009, and stage 4, 0% vs. 13%, P = 0.04). Surveillance correlated with earlier diagnoses for ulcerative colitis- and Crohn's disease-associated intestinal cancers, whereas shorter intervals between endoscopic examinations correlated with an earlier cancer diagnosis in ulcerative colitis patients but not in Crohn's disease patients. CONCLUSIONS: The clinical and oncological features of ulcerative colitis- and Crohn's disease-associated cancers were very different. Crohn's disease-associated cancers were diagnosed at more advanced stages and were detected less frequently by surveillance. Additionally, they showed a significantly poorer prognosis.

[Surgical ulcerative colitis complicated by multiple lung abscesses secondary to septic pulmonary embolism after multidrug immunosuppressive therapies].

This is a case implying a serious infectious complication risk during intensive severe ulcerative colitis treatment. A 26-year-old man developed diarrhea and bloody stool who was diagnosed with ulcerative colitis in 2018. He was managed with 5-aminosalicylic acid, but intolerance reaction resulted in discontinuation of treatment. He relapsed with severe abdominal pain and bloody stools in February 2019. He was referred to our department for intensive therapy. He had been treated with steroids, tacrolimus, granulocyte and monocyte apheresis, infliximab or tofacitinib, which temporarily improved his clinical symptoms. However, his medical condition could not be controlled. Hand-assisted laparoscopic subtotal colectomy was then performed in October 2019. He developed intermittent fever on postoperative day 3. Enhanced computed tomography (CT) revealed multiple deep vein thromboses and pulmonary embolism. Antibiotics and anticoagulation therapy were initiated, but postoperative day 13 CT showed multiple pulmonary cavities containing fluids and air, which were diagnosed as pulmonary abscess. His intermittent fever was over 38.0°C. Severe cough and hemoptysis lasted 3 weeks, the clinical symptoms and laboratory data then gradually improved after the fourth week.

Inflammatory bowel disease-specific findings are common morphological changes in the ileal pouch with ulcerative colitis.

Why inflammation is common in ileal pouches with ulcerative colitis (UC) is unclear. We therefore clarified the morphological changes in pouches and afferent limbs (AL) of patients with UC and explored the relationship between these findings. We evaluated the morphological findings (histological and endoscopic inflammation as the Pouchitis Disease Activity Index [PDAI] histology subscore [hPDAI] and endoscopy subscore [ePDAI], inflammatory bowel disease [IBD]-specific findings using the IBD score [SIBD], colonic metaplasia using the colonic metaplasia score [CMS], and goblet cell [GC] ratio) in the pouch and AL of patients with UC. A total of 261 pouchoscopies were analyzed. The pouch body had a higher hPDAI (p < 0.001), SIBD (p < 0.001), CMS (p < 0.001), GC ratio (p < 0.001), and ePDAI (p < 0.001) than the AL. The hPDAI was correlated with the SIBD (Spearman's coefficient r = 0.538; p < 0.001), CMS (r = 0.687; p < 0.001), and the ePDAI (r = 0.552; p < 0.001), but not with GC ratio (r = 0.175; p < 0.001) or the pouch usage duration (r = -0.057; p = 0.107). The incidence of histological inflammation was higher in specimens showing basal plasmacytosis with severe mononuclear cell infiltration (BP) than in those without BP (odds ratio [OR] 6.790, p < 0.001), BP was commonly found with crypt hyperplasia (OR 3.414, p < 0.001) and the crypt length correlated with neutrophil infiltration (r = 0.469; p < 0.001). Histological inflammation, colonic metaplasia, the GC ratio, endoscopic inflammation, and IBD-specific findings were commonly present in the pouch than in the AL. Histological inflammation occurs with IBD-specific findings and colonic metaplasia, and these signify endoscopic inflammation.

Progression of ulcerative colitis following diversion colitis.

Diversion colitis and ulcerative colitis (UC) can be caused by different mechanisms; however, several case reports have described the development of typical UC following diversion colitis. A 63-year-old man underwent Hartmann's operation following a diagnosis of perforation of a sigmoid colon diverticulum and peritonitis. Stoma closure was performed 4 months later, and the portion of the sigmoid colon with the diverticulum was unintentionally left as a blind end. Following stoma closure, hematochezia worsened, and he was diagnosed as having developed diversion colitis only in the blind sigmoid colon. Intermittent use of topical mesalazine enemas controlled the bowel symptoms; however, 4 years after the stoma closure, bloody stools were observed again. Colonoscopy revealed coarse and friable granular mucosa with adherent mucopurulent exudate in the rectum, and mucosal erythematous edema with adherent mucopurulent exudate in the blind sigmoid colon. The histological findings indicated basal plasmacytosis, and goblet cell depletion and cryptitis in the lamina propria, which is characteristic of UC. To the best of our knowledge, this is the fourth description of a patient who developed UC following diversion colitis. Local inflammation may have triggered the development of UC through hematogenous or lymphogenous circulation of lymphocytes or autoantibodies.

Postoperative complications, bowel function, and prognosis in restorative proctocolectomy for ulcerative colitis-a single-center observational study of 320 patients.

PURPOSE: To determine the selection criteria, postoperative complications, bowel function, and prognosis of stapled ileal pouch-anal anastomosis (IPAA) and hand-sewn IPAA for ulcerative colitis (UC). METHODS: We defined our surgical indications and strategy, and compared the postoperative complications, bowel function, and prognoses between patients who underwent stapled and hand-sewn IPAA for UC at the Yokohama City University Medical Center between 2004 and 2017. RESULTS: Among 320 patients enrolled, 298 patients underwent stapled IPAA while 22 underwent hand-sewn IPAA. There was no significant difference in the postoperative complications between the two groups. Regarding postoperative bowel function, stapled IPAA caused significantly less soiling (stapled vs hand-sewn: 9.1% vs 41.0%, odds ratio (OR) = 0.14, p < 0.0002), spotting (stapled vs hand-sewn: 23.2% vs 63.6%, OR = 0.17, p < 0.0001), and difficulty in distinguishing feces from flatus (stapled vs hand-sewn: 39.9% vs 63.6%, OR = 0.36, p < 0.026). No postoperative neoplasia was observed at the final follow-up in all patients. CONCLUSION: In this study, there was no clear difference in the postoperative complications between stapled and hand-sewn IPAA, but stapled IPAA resulted in better postoperative bowel function. Postoperative oncogenesis from the residual mucosa is rare. However, future cancer risk remains; thus, careful follow-up is required.

Preoperative risk factors of incisional surgical site infection in severe or intractable ulcerative colitis.

PURPOSE: The present study explored preoperative risk factors (predictors) of incisional surgical site infection (I-SSI) in severe or intractable ulcerative colitis (UC). METHODS: This was a retrospective study of 230 consecutive patients who underwent primary surgery for UC. Patients whose surgical indications were UC with cancer or dysplasia were excluded. SSI was defined as an infection according to the Centers for Disease Control and Prevention Guidelines. Preoperative variables were examined by univariate, receiver operating characteristic curve, and multivariate analyses. RESULTS: We analyzed 208 patients in this study. In a multivariate logistic analysis, C-reactive protein (CRP) ≥ 1.7 mg/dl [odds ratio (OR) 5.35; 95% confidence interval (CI) 1.50-19.06; p = 0.01), albumin ≤ 2.4 g/dl (OR 5.77; 95% CI 1.41-23.57; p = 0.02), and preoperative blood transfusion (OR 3.21; 95% CI 1.04-9.96; p = 0.04) were predictors of I-SSI. Patients with all predictors had a more than 50% incidence of I-SSI, a higher incidence of all severe complications (13.6% vs. 3.2%; p = 0.02), and a longer postoperative hospital stay (19.5 vs. 17.0 days, p = 0.04) than the other patients. CONCLUSIONS: CRP ≥ 1.7 mg/dl, albumin ≤ 2.4 g/dl, and transfusion are predictors of I-SSI in severe or intractable UC. Clinician should carefully evaluate the surgical options before these predictors appear.

Preoperative prevalence and risk factors of deep-vein thrombosis in Japanese surgical patients with ulcerative colitis: a retrospective investigational study.

PURPOSE: The purpose of this study was to clarify the perioperative deep-vein thrombosis (DVT) prevalence and its risk factors in surgical ulcerative colitis (UC) patients by comparing the results with those in surgical colorectal cancer (CRC) patients at a high risk of perioperative venous thrombosis. METHODS: This retrospective, observational study included patients who underwent surgery for UC or CRC between January 2013 and October 2019. Consecutive surgical patients with a positive D-dimer assay result (≥ 1.0 µg/ml) underwent lower-extremity venous ultrasonography. The prevalence and risk factors for preoperative DVT were examined in UC patients. RESULTS: A total of 101 UC patients and 593 CRC patients were deemed eligible. Among the D-dimer positive cases, there were no significant differences between the two groups in the preoperative DVT prevalence (UC: 21.8% vs. CRC: 28.8%, p = 0.151), distal type (18.8% vs. 27.2%, p = 0.086), or proximal type (5.9% vs. 4.2%, p = 0.434). Furthermore, multivariate analyses showed that an older age, overweight status, poor ASA status, and a high preoperative dose of steroid were independent risk factors for preoperative DVT in UC surgical patients. CONCLUSIONS: The risk of perioperative thrombosis in UC patients was considered similar to that in CRC, so active thromboprophylaxis should be administered to UC patients while paying attention to bleeding. TRIAL REGISTRATION: This study was registered with the Japanese Clinical Trials Registry as UMIN000042004 ( http://www.umin.ac.jp/ctr/index.htm ).

Perioperative Venous Thromboembolism in Ulcerative Colitis: A Multicenter Prospective Study in Japan.

Background: Recently, the prevalence of venous thromboembolism (VTE) in Asian patients with inflammatory bowel disease (IBD) is gradually increasing. IBD surgery is a well-recognized risk factor for VTE. However, there are no prospective studies about VTE after surgery for ulcerative colitis (UC) in Asia. This multicenter prospective study aimed to clarify the prevalence and risk factors for perioperative VTE in UC surgery in Japan. Methods: A total of 134 patients with UC were included from January 1, 2013 to December 31, 2014. Preoperative screening was performed in all patients. In the perioperative period, standard VTE prophylaxis based on risk assessment was administered. The prevalence of pre- and postoperative VTE, its risk factors, and mortality rates were investigated. Results: Perioperative deep vein thrombosis and pulmonary embolism were diagnosed in 15 (11.1%) and 1 patient (0.7%), respectively. All patients were asymptomatic. No surgery-related deaths were found (mortality rate 0%). Seven patients (5.2%) were diagnosed, and 8 (6.4%) during postoperative follow-up by ultrasonography or computed tomography. Forty-seven percent of VTE cases was developed preoperatively. A preoperative hospital length stay of over 5 days was a significant risk factor [P = 0.04; odds ratio: 8.26 (1.06-64.60)] for preoperative VTE. Postoperative deep vein thrombosis occurred in 8 of the 127 patients (6.4%). Six out of these 8 (75.0%) occurred after postoperative day 14. Perioperative blood transfusion was a significant risk factor [P = 0.04; odds ratio: 8.26 (1.06-64.60)] for postoperative VTE. Conclusion: A VTE-conscious perioperative management is as necessary in Asia as in Western countries.