Prognostic Factors for Severe-to-Fatal Post-Endoscopic Retrograde Cholangiopancreatography Pancreatitis: A Multicenter Prospective Cohort Study.

The prognostic factors associated with severe-to-fatal post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis (PEP) remain unclear despite the extensive number of studies on PEP. In total, 3739 ERCP patients with biliary disease with an intact papilla and indicated for ERCP were prospectively enrolled at 36 centers from April 2017 to March 2018. Those with acute pancreatitis diagnosed before ERCP, altered gastrointestinal anatomy, and an American Society of Anesthesiologists (ASA) physical status > 4 were excluded. Univariate and multivariate logistic regression analyses were performed on patient-related factors, operator-related factors, procedure-related factors, and preventive measures to identify potential prognostic factors for severe-to-fatal PEP. Multivariate analyses revealed pancreatic guidewire-assisted biliary cannulation (OR 13.59, 95% CI 4.21-43.83, p < 0.001), post-ERCP non-steroidal anti-inflammatory drug (NSAID) administration (OR 11.54, 95% CI 3.83-34.81, p < 0.001), and previous pancreatitis (OR 6.94, 95% CI 1.45-33.33, p = 0.015) as significant risk factors for severe-to-fatal PEP. Preventive measures included endoscopic biliary sphincterotomy (EST; OR 0.29, 95% CI, 0.11-0.79, p = 0.015) and prophylactic pancreatic stents (PPSs; OR 0.11, 95% CI, 0.01-0.87, p = 0.036). In biliary ERCP, pancreatic guidewire-assisted biliary cannulation, NSAID administration after ERCP, and previous pancreatitis were risk factors for severe-to-fatal PEP, whereas EST and PPS were significant preventive measures for severe-to-fatal PEP.

Does endoscopic sphincterotomy contribute to the prevention of post-endoscopic retrograde cholangiopancreatography pancreatitis after endoscopic biliary stenting for malignant biliary obstruction? A multicenter prospective cohort study.

BACKGROUND: There is no consensus on the necessity of endoscopic sphincterotomy (ES) to prevent post-endoscopic retrograde cholangiopancreatography pancreatitis (PEP) after endoscopic stenting in patients with malignant biliary obstruction. We investigated the incidence of PEP after endoscopic biliary stenting for malignant biliary obstruction with or without ES in a multicenter prospective cohort study. METHODS: We enrolled 807 patients who underwent endoscopic biliary stenting for malignant biliary obstruction with a native papilla at 36 hospitals between April 2017 and March 2018. The incidence of PEP in patients with or without ES was compared for subgroups based on stent type, placement method, and patient background. Univariate and multivariate analysis was performed to investigate the incidence of PEP in all stenting patients. RESULTS: Plastic and metal stents (MS) were inserted in 598 and 209 patients, respectively. The incidence of PEP in patients with or without ES was 7.9% and 7.4%, respectively among all stenting patients. The incidences of PEP with or without ES in plastic stent insertion patients, patients with MS insertion, stent insertions across the papilla, stent insertions across the papilla in patients without main pancreatic duct obstruction, and fully covered MS insertions across the papilla were compared. There was no overall significant difference in the incidence of PEP between those with or without ES. Multivariate logistic regression analysis for the incidence of PEP in all stenting patients revealed obstruction of the main pancreatic duct at the pancreatic head and epinephrine spraying on the papilla were significant factors; there was no significant difference in the incidence of PEP between patients with or without ES. CONCLUSION: Endoscopic sphincterotomy may not contribute to the prevention of PEP after endoscopic biliary stenting for malignant biliary obstruction, even in cases of insertion with a fully covered MS across the papilla.

The effectiveness of a nonalcoholic disinfectant containing metal ions, with broad antimicrobial activity.

Disinfectants have different efficacies depending on their use and the target microorganism. This study aimed to evaluate the efficacy and safety of our new nonalcoholic disinfectant, which consists mainly of metal ions. According to the 17th revised Japanese Pharmacopoeia and ASTM international E1052 method, the bactericidal and virucidal efficacy of this new disinfectant against 13 microorganisms was evaluated by the in vitro quantitative suspension test. Additionally, the disinfectant cytotoxicity against multiple cell lines was examined. Then, a safety test using a human open patch test was performed with 26 healthy volunteers. This disinfectant showed strong bactericidal and virucidal activities: all microorganisms except enterovirus were inactivated very quickly. The infectivity of 12 microbial strains was eliminated within 5 min of disinfectant exposure. Additionally, this disinfectant showed little acute cytotoxicity in vitro. All volunteers were negative in the human open patch test. Our new disinfectant has a broad spectrum of microbial targets, is safe for human skin, and demonstrates no cytotoxicity. This disinfectant could prevent common microbial infections.

Comparison of double-layer large-diameter and conventional small-diameter plastic stents for preoperative biliary drainage in resectable distal malignant biliary obstruction.

The use of a plastic stent (PS) in resectable patients with distal malignant biliary obstruction (DMBO) is uncommon due to the high failure rate of this method. This study evaluated the efficacy and safety of a double-layer, large-diameter PS as a bridge to surgery compared with a conventional PS. This was a single-center retrospective cohort study. In total, 129 consecutive patients with DMBO underwent pancreaticoduodenectomy between January 2011 and March 2018. Fifty-five patients who preoperatively underwent plastic biliary drainage were enrolled. The patients were divided into two groups based on stent diameter: a large-diameter plastic stent (LPS) group and a small-diameter plastic stent (SPS) group. The primary endpoint was the stent patency period, and the secondary endpoint was the medical cost. Thirty-six patients received SPSs; 19 patients received LPSs. The patency rate until surgery was significantly higher in the LPS group than in the SPS group (89.5% vs. 41.7%, P = 0.0006). Multivariate analysis revealed that LPS use was significantly associated with sufficient stent patency. The total cost of LPS use was significantly lower than that of SPS use. LPSs had longer patency and reduced medical costs than SPSs. LPSs may be suitable for patients with DMBO who are scheduled to undergo surgery.

A Triple-Drug Blister-Packaged Drug with Vonoprazan Improves First-Line Eradication of Helicobacter pylori in Elderly Patients: A Retrospective Propensity Score-Matched Cohort Study.

BACKGROUND: A blister-packaged drug might be useful to enhance the eradication of Helicobacter pylori. We investigated the effect of a blister-packaged drug for H. pylori eradication. METHODS: We treated 1,758 patients with H. pylori infections and evaluated the successful eradication rate in patients who underwent first-line eradication between January 2013 and May 2018. Treatments included a conventional proton pump inhibitor (PPI) blister-packaged drug containing lansoprazole or rabeprazole with clarithromycin (CAM) and amoxicillin (AC), vonoprazan (VPZ) with CAM and AC in a separate tablet, or a VPZ blister-packaged drug (VONOSAP) containing VPZ with CAM and AC, with all drugs given twice daily for 7 days. RESULTS: Finally, we evaluated 1,263 patients (conventional PPI: n = 644, VPZ: n = 326, and VONOSAP: n = 293). The overall successful eradication rates were 71.9% in the conventional PPI group, 90.2% in the VPZ group, and 92.2% in the VONOSAP group. There was a significantly lower eradication rate in the PPI group than in the VPZ and VONOSAP (p < 0.00001, p < 0.0001) groups, but there was no significant difference between the VPZ and VONOSAP groups (p = 0.4006). We enrolled a total of 256 age- and gender-matched patients in the VPZ and VONOSAP groups, and both groups had successful eradication rates of approximately 90% (89.8 vs. 90.4%, respectively, p = 0.7641). After analyzing the subgroup of patients older than 75 years, there was a significant treatment benefit of VONOSAP but not of VPZ in elderly patients (EPs). CONCLUSION: Triple-drug blister-packaged drugs including VPZ may improve the first-line eradication of H. pylori in EPs.

Prediction and clinical implications of HBV reactivation in lymphoma patients with resolved HBV infection: focus on anti-HBs and anti-HBc antibody titers.

Hepatitis B virus (HBV) reactivation (HBV-R) and hepatitis related to HBV-R are well-recognized complications that occur in patients who have undergone cytotoxic chemotherapy or immunosuppressive therapy. The degree of HBV-R in this population varies from self-limited or asymptomatic hepatitis to acute liver failure, which may lead to life-threatening events. However, no established treatment or standard surveillance method exists for monitoring patients to predict the development of HBV-R during or after chemotherapy or immunosuppressive therapy, particularly regarding resolved HBV infection. Prophylactic antiviral agents and regular monitoring of HBV-DNA levels are known to be useful methods for preventing HBV-R; however, these methods require considerable financial resources, and such resources are limited in the endemic areas of HBV infection. Most patients with resolved HBV infection do not develop a hepatitis flare or self-limited HBV-R with only an increase in HBV DNA. However, some patients may develop HBV-R even 1 year or more after the last chemotherapy treatment. Therefore, predicting the development of HBV-R and its timing is difficult, and exploring markers that could help predict whether or when HBV reactivation occurs is necessary. In this review, we address the predictive risk factors for HBV-R in patients with resolved HBV infection, focusing on the ability of anti-HBs and anti-HBc to predict HBV-R. We conclude that the combination of anti-HBc and anti-HBs titers may be a reliable and useful predictor for managing HBV-R.

Follicular cholangitis mimicking cholangiocarcinoma treated with right hepatectomy: A case report and review of published works.

Follicular cholangitis is a new, rare disease that causes severe biliary stricture. We herein describe the findings from a resected case of follicular cholangitis, suggesting a distinct disease entity that causes benign biliary stricture. A 60-year-old man who was referred to our hospital due to elevated γ-glutamyl transpeptidase levels and dilatation of the B8 bile duct. Although bile juice cytology and bile duct brushing cytology showed no malignancy, the dilatation was progressive. Therefore, right hepatectomy combined with caudate lobectomy was carried out on suspicion of intrahepatic cholangiocarcinoma. The wall of the resected bile duct was markedly thickened due to severe fibrosis under the mucosal layer. Histology of the mucosal epithelium indicated no malignancy. Infiltration of plasma cells characterized by remarkable formation of lymphoid follicles with germinal centers was observed around the bile ducts. The patient was diagnosed with follicular cholangitis based on histological findings. We thus observed a rare case of follicular cholangitis. This case and review of published reports suggest that, despite its rarity, follicular cholangitis should be considered at the differential diagnosis of biliary stricture. This case report could contribute to a better understanding of how to address this disease.

Impact of time from diagnosis to chemotherapy in advanced gastric cancer: A Propensity Score Matching Study to Balance Prognostic Factors.

BACKGROUND: It is unclear whether treatment delay affects the clinical outcomes of chemotherapy in advanced gastric cancer (A-GC). AIM: To assess whether treatment delay affects the clinical outcomes of chemotherapy in A-GC. METHODS: This single-center retrospective study examined consecutive patients with A-GC between April 2012 and July 2018. In total, 110 patients with stage IV A-GC who underwent chemotherapy were enrolled. We defined the wait time (WT) as the interval between diagnosis and chemotherapy initiation. We evaluated the influence of WT on overall survival (OS). RESULTS: The mean OS was 303 d. The median WT was 17 d. We divided the patients into early and elective WT groups, with a 2-wk cutoff point. There were 46 and 64 patients in the early and elective WT groups, respectively. Compared with the elective WT group, the early WT group had significantly lower albumin (Alb) levels and higher neutrophil/lymphocyte ratios and C-reactive protein (CRP) levels but not a lower performance status. The elective WT group underwent more combination chemotherapy than did the early WT group. OS was different between the two groups (230 d vs 340 d, respectively). Multivariate analysis revealed that higher CRP levels, lower Alb levels and monotherapy were significantly related to a poor prognosis. To minimize potential selection bias, patients in the elective WT group were 1:1 propensity score matched with patients in the early WT group; no significant difference in OS was found (303 d vs 311 d, respectively, log-rank P = 0.9832). CONCLUSION: A longer WT in patients with A-GC does not appear to be associated with a worse prognosis.

Prediction of survival benefit when deciding between chemotherapy and best supportive therapy in elderly patients with advanced gastric cancer: A retrospective cohort study.

It remains unclear whether elderly patients (EPs) with advanced gastric cancer (AGC) benefit from chemotherapy. The aim of the present study was to examine the prognostic factors for EPs with AGC in order to generate a prognosis-predicting scoring system. This single-center retrospective study examined consecutive patients with AGC between April 2012 and July 2017. Risk factors for survival in EPs aged ≥75 years were identified using a Cox proportional hazards model, and a prognostic scoring system was generated and retrospectively evaluated to determine its usefulness for predicting patient prognosis. A total of 61 patients were enrolled as EPs (mean age, 81 years) and compared with 80 non-EPs (mean age, 66 years). The median survival time (MST) was significantly longer for non-EPs compared with that for EPs (3.8 vs. 10.1 months, respectively; P=0.0447). Among the EPs, 29 (48%) received chemotherapy and 32 received best supportive care (BSC). A total of 68 non-EPs (85%) received chemotherapy and 12 non-EPs received BSC. Among EPs with AGC, age-adjusted multivariate analysis revealed that performance status (PS), neutrophil/lymphocyte ratio (NLR)<4, intestinal-type histology and chemotherapy were significant prognostic factors. To predict EPs too frail for chemotherapy prior to treatment, one point was assigned for a PS of 1, diffuse-type histology and NLR≥4, whereas 2 points were assigned for PS≥2, and the point totals for each patient were calculated. A cut-off point of 2 had the best P-value by the log-rank test and was used to divide the patients into low-risk (LoR: Score 0-1) and high-risk (HiR: Score 2-4) groups. The MST of the LoR and HiR groups was 23.6 and 3.6 months, respectively (P<0.001). As regards treatment strategies and risk groups, the LoR chemotherapy group had the best prognosis (P=0.0010), and LoR EPs who were administered chemotherapy had a longer MST (30.3 months) compared with EPs who received BSC (8.7 months). In conclusion, scoring systems using PS, histology and NLR may be useful when considering chemotherapy in EPs with AGC.

Distinct Clinical Factors in Hospitalized Patients with Diverticular Bleeding and Diverticulitis.

BACKGROUND/AIMS: It is unclear why colonic diverticular bleeding and diverticulitis rarely coexist. This study compared the characteristics of these conditions. METHODS: This single-center retrospective study examined 310 consecutive patients hospitalized with an episode of diverticular disease (cases) and outpatients without a diverticular episode (controls) from January 2012 to December 2015. We investigated distinct clinical factors in hospitalized patients with diverticular bleeding and diverticulitis. RESULTS: We identified 183 patients with 263 episodes of diverticular bleeding and 127 patients with 135 episodes of diverticulitis during the study period. Patients with diverticular bleeding were significantly older than those with diverticulitis (median age 76 vs. 56 years) and had more cardiovascular disease, hypertension, diabetes, cerebrovascular disease, chronic kidney disease, lipid disorder, or a poorer performance status. Significantly more diverticular bleeding patients were taking antiplatelet drugs, anticoagulant drugs, proton pump inhibitors, or laxative agents. Multivariate analysis revealed that an age > 65 years (OR 5.42), and antiplatelet agent use (OR 7.29) were more significant risk factors for diverticular bleeding than for diverticulitis. CONCLUSIONS: Elderly people using antiplatelet drugs may be more susceptible to diverticular bleeding than diverticulitis.

Correction: Radiation exposure dose and influencing factors during endoscopic retrograde cholangiopancreatography.

[This corrects the article DOI: 10.1371/journal.pone.0207539.].

Alveolar Echinococcosis Mimicking a Hepatic Neoplasm with Lymph Node Metastasis: A Case Report.

A 37-year-old man had an asymptomatic 17-mm mass in the liver by health check with ultrasonography. Five years later, he was referred to our hospital because the mass was slightly enlarged with a peripancreatic lymph node. We performed endoscopic ultrasonography fine-needle aspiration (EUS-FNA) to evaluate a lymph node, but it showed amorphous eosinophilic material and eosinophilic infiltrate in necrotic tissue of toothpaste-like white specimen. However, we diagnosed as potentially malignant liver mass with lymph node metastasis because of 2-deoxy-2-(fluorine-18) fluorodeoxyglucose uptake. We then performed hepatectomy and enucleation of the pancreas. DNA polymerase chain reaction analysis revealed Echinococcus multilocularis infection. Retrospectively, we could find a part of Echinococcus in the specimens of EUS-FNA.

Radiation exposure dose and influencing factors during endoscopic retrograde cholangiopancreatography.

INTRODUCTION: Various endoscopic procedures under fluoroscopic guidance are being rapidly adopted, and radiation exposure is considered to be increasing. However, there is little concern about this issue in gastroenterology practice. This study aims to evaluate the actual radiation exposure dose (RD) during endoscopic retrograde cholangiopancreatography (ERCP) and the factors affecting the RD. METHODS: In this retrospective, single-center cohort study of 1157 consecutive patients who underwent ERCP between October 2012 and February 2017, we analyzed the influences of patient characteristics, procedure time (min), total fluoroscopy time (min), type of processing engine, experience of the endoscopist, and type of disease on the total RD (mGy). RESULTS: The median procedure times were 28 min for common bile duct stones (CBDS), 25 min for distal malignant biliary obstruction (MBO), and 30 min for proximal MBO. Similarly, the median fluoroscopy times were 10.3, 8.8, and 13.4 min, and the median RDs were 167, 123, and 242 mGy, respectively. Proximal MBO required significantly longer procedure time and fluoroscopy time and resulted in greater RD than distal MBO (P = 0.0006, <0.0001, <0.0001) and CBDS (P = 0.015, <0.0001, <0.0001). Multiple linear regression showed that distal MBO and a novel processing engine negatively correlate with RD (P = 0.04, <0.0001) and that proximal MBO positively correlates with RD (P = 0.0001). DISCUSSION: Procedure time and fluoroscopy time were significantly longer for proximal MBO than for CBDS and distal MBO. The type of disease and processing engine significantly influenced the RD during ERCP.

Number of polyps detected is a useful indicator of quality of clinical colonoscopy.

BACKGROUND AND STUDY AIMS: Adenoma detection rate (ADR) is a well-known quality indicator (QI) for colonoscopy. It is, however, difficult to evaluate ADR during practice. The aim of this study was to investigate the number of endoscopically detected polyps as a QI for colonoscopy. PATIENTS AND METHODS: This was a retrospective single-center cohort study of 5,190 consecutive patients who underwent colonoscopy from January 2015 to May 2016. Among these patients, we ultimately enrolled 1,937 patients for initial colonoscopy. We evaluated QIs including bowel preparation, cecum intubation time, withdrawal time, number of endoscopically detected polyps, ADR and advanced neoplasia detection rate (ANDR). RESULTS: The mean number of endoscopically detected polyps, ADR and ANDR were 1.5 ±â€Š2.3 (95 % confidence interval (CI)1.4 - 1.6), 38.6 % (95 % CI 36.5-40.8), and 18.3 % (95 % CI 16.6 - 20.1), respectively. ADR and ANDR increased with the number of endoscopically detected polyps, but the correlation reached a plateau at five or more polyps. We divided the patients into three groups based on the number of polyps (1 to 2, 3 to 4, and 5 or more). Logistic regression analysis adjusted by age and sex revealed that presence of a large number of polyps was a strong predictor of advanced neoplasia (odds ratio: 3.1 [95 % CI 2.2 - 4.3] for 3 to 4 polyps and 7.9 [95 % CI 5.4 - 11.8] for 5 or more polyps when using the presence of 1 or 2 polyps as a reference). CONCLUSION: The number of endoscopically detected polyps can predict risk of advanced neoplasia and may thus be a new QI for colonoscopy.

Nivolumab Induces Sustained Liver Injury in a Patient with Malignant Melanoma.

A 42-year-old man was diagnosed with cStage IIIb malignant melanoma and underwent resection. After interferon-beta therapy, 18-fluorodeoxyglucose-positron emission tomography/computed tomography (18F-FDG PET/CT) showed multiple lung metastases, and he received nivolumab (2 mg/kg) every 3 weeks, resulting in a total of 17 cycles. After treatment, 18F-FDG PET/CT showed a significant decrease in the size of the metastases, but he had a Grade 4 alanine aminotransferase (ALT) elevation. Liver histology revealed drug-induced liver damage. Therefore, we performed steroid half-pulse therapy followed by oral methylprednisolone, but his ALT level did not completely recover to the normal range even after five months. We herein report a case with specific, sustained liver injury induced by nivolumab as an immune-related adverse events.

Clinically diagnosed late-onset fulminant Wilson's disease without cirrhosis: A case report.

A 64-year-old woman was referred to our hospital with jaundice of the bulbar conjunctiva and general fatigue. After admission, she developed hepatic encephalopathy and was diagnosed with fulminant hepatitis based on the American Association for the Study of Liver Disease (AASLD) position paper. Afterwards, additional laboratory findings revealed that serum ceruloplasmin levels were reduced, urinary copper levels were greatly elevated and Wilson's disease (WD)-specific routine tests were positive, but the Kayser-Fleischer ring was not clear. Based on the AASLD practice guidelines for the diagnosis and treatment of WD, the patient was ultimately diagnosed with fulminant WD. Then, administration of penicillamine and zinc acetate was initiated; however, the patient unfortunately died from acute pneumonia on the 28th day of hospitalization. At autopsy, the liver did not show a bridging pattern of fibrosis suggestive of chronic liver injury. Here, we present the case of a patient with clinically diagnosed late-onset fulminant WD without cirrhosis, who had positive disease-specific routine tests.

The combination of anti-HBc and anti-HBs levels is a useful predictor of the development of chemotherapy-induced reactivation in lymphoma patients with resolved HBV infection.

Fatal chemotherapy-induced hepatitis B virus reactivation (HBV-R) is a well-described serious complication observed in patients with lymphoma and resolved HBV infection. The aim of the present study was to determine the predictive factors of the development of chemotherapy-induced HBV-R. A total of 77 consecutive newly diagnosed patients with lymphoma and resolved HBV infection, who received chemotherapy from 2007 through 2015 were analysed retrospectively. Significant predictive factors associated with HBV-R were identified based on the data from these patients. Ten patients developed HBV-R during and following chemotherapy, and two of these 10 patients developed HBV-associated hepatitis flares. There was a significant negative correlation between anti-hepatitis B core (HBc) titres prior to chemotherapy and time to HBV-R (P=0.016, R=-0.732). Univariate and multivariate logistic regression analyses demonstrated that anti-HBc and anti-hepatitis B surface (HBs) titres at baseline were significant predictive factors for HBV-R. In addition, patients with high anti-HBc titres at baseline (above 10 S/CO) were significantly more likely to experience HBV-R than patients with low anti-HBc and high anti-HBs titres (above 28 mIU/ml), who did not experience complete reactivation (P<0.0001). Furthermore, patients with low anti-HBs titres were significantly more likely to experience HBV-R than those with high anti-HBs titres (P=0.031). All HBV-R episodes among the patients with high anti-HBc titres occurred within 3 months following the initiation of chemotherapy. The combination of anti-HBc and anti-HBs titres, as opposed to either titre alone, at baseline in patients with lymphoma may serve as a surrogate marker for the occurrence of HBV-R under the influence of chemotherapy.

Frequency of coexistent carcinoma in sessile serrated adenoma/polyps and traditional serrated adenomas removed by endoscopic resection.

BACKGROUND AND STUDY AIMS: Sessile serrated adenoma/polyps (SSA/Ps) have a different potential than traditional adenomatous polyps for developing into malignant colorectal cancer. However, little is known about the coexistent cancer rate. Here, we evaluate the frequency of carcinoma in serrated polyps removed by endoscopic resection (ER). PATIENTS AND METHODS: This was a retrospective single-center cohort study of consecutive patients with colorectal polyps who underwent ER from March 2003 to October 2014. We determined the frequency of serrated polyps among all resected colorectal polyps and analyzed the clinicopathological findings as well as the frequency and characteristics of coexistent carcinoma in the serrated polyps resected by ER based on pathology reports. RESULTS: A total of 21,048 polyps from 15,326 patients were identified, including 15,984 traditional adenomatous polyps (75.9 %), 621 SSA/Ps (3.0 %), 136 traditional serrated adenomas (TSAs) (0.6 %), 1,121 hyperplastic polyps (5.3 %), and 3,186 polyps of other types (15.1 %). The clinical and endoscopic findings of SSA/Ps revealed a male predominance (68.6 %), with 61.7 % of the polyps located in the proximal colon. Males accounted for 77.2 % of all patients with TSAs, and 77.2 % of these polyps were located in the distal colon. The mean sizes of the SSA/Ps and TSAs were 8.8 and 10.7 mm, respectively. Among the SSA/Ps, 8 (1.3 %) cases had coexistent carcinoma, and 1 (0.7 %) patient with TSA showed coexistent carcinoma. In the patients with SSA/Ps, female sex and a tumor size ≥ 10 mm were predictive factors for coexistent carcinoma. CONCLUSIONS: The frequency of SSA/Ps with carcinoma was lower than that for traditional adenoma. Female sex and tumor size ≥ 10 mm were significant predictive factors for coexistent carcinoma.