Clinical Evaluation of Computer-Aided Colorectal Neoplasia Detection Using a Novel Endoscopic Artificial Intelligence: A Single-Center Randomized Controlled Trial.

INTRODUCTION: Computer-aided diagnostic systems are emerging in the field of gastrointestinal endoscopy. In this study, we assessed the clinical performance of the computer-aided detection (CADe) of colonic adenomas using a new endoscopic artificial intelligence system. METHODS: This was a single-center prospective randomized study including 415 participants allocated into the CADe group (n = 207) and control group (n = 208). All endoscopic examinations were performed by experienced endoscopists. The performance of the CADe was assessed based on the adenoma detection rate (ADR). Additionally, we compared the adenoma miss rate for the rectosigmoid colon (AMRrs) between the groups. RESULTS: The basic demographic and procedural characteristics of the CADe and control groups were as follows: mean age, 54.9 and 55.9 years; male sex, 73.9% and 69.7% of participants; and mean withdrawal time, 411.8 and 399.0 s, respectively. The ADR was 59.4% in the CADe group and 47.6% in the control group (p = 0.018). The AMRrs was 11.9% in the CADe group and 26.0% in the control group (p = 0.037). CONCLUSION: The colonoscopy with the CADe system yielded an 11.8% higher ADR than that performed by experienced endoscopists alone. Moreover, there was no need to extend the examination time or request the assistance of additional medical staff to achieve this improved effectiveness. We believe that the novel CADe system can lead to considerable advances in colorectal cancer diagnosis.

Endoscopic three-categorical diagnosis of Helicobacter pylori infection using linked color imaging and deep learning: a single-center prospective study (with video).

BACKGROUND: Helicobacter pylori (H. pylori) eradication is required to reduce incidence related to gastric cancer. Recently, it was found that even after the successful eradication of H. pylori, an increased, i.e., moderate, risk of gastric cancer persists in patients with advanced mucosal atrophy and/or intestinal metaplasia. This study aimed to develop a computer-aided diagnosis (CAD) system to classify the status of H. pylori infection of patients into three categories: uninfected (with no history of H. pylori infection), currently infected, and post-eradication. METHODS: The CAD system was based on linked color imaging (LCI) combined with deep learning (DL). First, a validation dataset was formed for the CAD systems by recording endoscopic movies of 120 subjects. Next, a training dataset of 395 subjects was prepared to enable DL. All endoscopic examinations were recorded using both LCI and white-light imaging (WLI). These endoscopic data were used to develop two different CAD systems, one for LCI (LCI-CAD) and one for WLI (WLI-CAD) images. RESULTS: The diagnostic accuracy of the LCI-CAD system was 84.2% for uninfected, 82.5% for currently infected, and 79.2% for post-eradication status. Comparisons revealed superior accuracy of diagnoses based on LCI-CAD data relative based on WLI-CAD for uninfected, currently infected, and post-eradication cases. Furthermore, the LCI-CAD system demonstrated comparable diagnostic accuracy to that of experienced endoscopists with the validation data set of LCI. CONCLUSIONS: The results of this study suggest the feasibility of an innovative gastric cancer screening program to determine cancer risk in individual subjects based on LCI-CAD.

Current status of first- and second-line Helicobacter pylori eradication therapy in the metropolitan area: a multicenter study with a large number of patients.

BACKGROUND: The environment surrounding Helicobacter pylori eradication treatment is dramatically changing. Recently, vonoprazan, a first-in-class potassium-competitive acid blocker (P-CAB), was introduced onto the market in 2015. The aging of Japan's demographic structure is becoming pronounced. In this study, we examined the trend of the eradication rate of H. pylori in the metropolitan area and examined factors concerning successful eradication. METHODS: We collected data from 20 hospitals in the Tokyo metropolitan area on patients who received first-line eradication therapy with a proton-pump inhibitor (PPI)/P-CAB, amoxicillin, and clarithromycin for 1 week and second-line eradication therapy with a PPI/P-CAB, amoxicillin, and metronidazole for 1 week from 2013 to 2018. The annual eradication rate and associated factors for successful eradication were analyzed. RESULTS: We collected data of 4097 and 3572 patients in the first- and second-line eradication therapies, respectively. The eradication rate decreased from 2013 to 2014 and increased again from 2015 to 2018 with the first-line therapy [the eradication rates in 2013, 2014, 2015, 2016, 2017 and 2018 were 71.8%, 63.7%, 78.5%, 84.6%, 89.7 and 90.1%, respectively, in the per protocol (PP)]. The second-line eradication rates were 90.0%, 82.6%, 88.8%, 87.5%, 91.8% and 90.1% in 2013, 2014, 2015, 2016, 2017 and 2018, respectively, in PP. Vonoprazan was an independent factor for successful eradication in not only first-line, but also second-line eradication. Age over 75 years was an independent factor for eradication failure in both first- and second-line eradication therapies. CONCLUSION: The eradication rate improved from 2015 to 2018 with the first-line therapy because of the introduction of vonoprazan in the market. The eradication rates with first- and second-line regimens in elderly patients were lower than those in younger patients.

Artificial intelligence diagnosis of Helicobacter pylori infection using blue laser imaging-bright and linked color imaging: a single-center prospective study.

BACKGROUND: Deep learning is a type of artificial intelligence (AI) that imitates the neural network in the brain. We generated an AI to diagnose Helicobacter pylori (H. pylori) infection using blue laser imaging (BLI)-bright and linked color imaging (LCI). The aim of this pilot study was to establish an AI diagnosing system that predicts H. pylori infection status using endoscopic images to improve the accuracy and productivity of endoscopic examination. METHODS: A total of 222 enrolled subjects (105 H. pylori-positive) underwent esophagogastroduodenoscopy and a serum test for H. pylori IgG antibodies. During esophagogastroduodenoscopy, an endoscopist sequentially took 3 still images of the lesser curvature of the stomach using white light imaging (WLI), BLI-bright, and LCI. EG-L580NW endoscopic equipment (FUJIFILM Co., Japan) was used for the study. The specifications of the AI were as follows: operating system, Linux; neural network, GoogLeNet; framework, Caffe; graphic processor unit, Geforce GTX TITAN X (NVIDIA Co., USA). RESULTS: The area under the curve (AUC) on receiver operating characteristics analysis was 0.66 for WLI. In contrast, the AUCs of BLI-bright and LCI were 0.96 and 0.95, respectively. The AUCs obtained for BLI-bright and LCI were significantly larger than those for WLI (P<0.01). CONCLUSIONS: The results demonstrate that the developed AI has an excellent ability to diagnose H. pylori infection using BLI-bright and LCI. AI technology with image-enhanced endoscopy is likely to become a useful image diagnostic tool.

Changes in the first line Helicobacter pylori eradication rates using the triple therapy-a multicenter study in the Tokyo metropolitan area (Tokyo Helicobacter pylori study group).

BACKGROUND AND AIM: Helicobacter pylori (H. pylori) infection is a strong risk factor for the development of gastric cancer. In 2013, the Japanese government approved H. pylori eradication therapy in patients with chronic gastritis as well as peptic ulcer. However, the continuing decline in eradication rates for first-line H. pylori eradication therapies is an urgent problem. In this study, we investigated changes in the first-line eradication rate from 2001 to 2010. METHODS: Eradication rates for 7-day triple therapy [proton pump inhibitor (rabeprazole 20 mg, lansoprazole 60 mg, or omeprazole 40 mg)+amoxicillin 1500 mg + clarithromycin (CAM) 400 or 800 mg, daily] were collated from 14 hospitals in the Tokyo metropolitan area. The urea breath test was used for the evaluation of eradication. The cut-off value was less than 2.5%. RESULTS: The yearly eradication rates (intention to treat/per protocol) were 78.5/79.5% (2001, n=242), 71.2%/72.9% (2002, n=208), 67.8%/70.5% (2003, n=183), 75.6%/84.6% (2004, n=131), 56.4%/70.5% (2005, n=114), 70.5%/75.8% (2006, n=271), 67.4%/82.0% (2007, n=135), 64.0%/76.3% (2008, n=261), 60.5%/74.3% (2009, n=329), and 66.5%/78.8% (2010, n=370), respectively. Examination of eradication rates according to CAM dosage revealed an eradication rate of 65.6% (383/584) for CAM 400 mg daily, and 68.5% (1124/1642) for CAM 800 mg daily, with no significant difference seen between dosages. CONCLUSION: In recent years, eradication rates for first-line triple therapy have obviously decreased, but no noticeable decrease has occurred after 2001.

Trends of second-line eradication therapy for Helicobacter pylori in Japan: a multicenter study in the Tokyo metropolitan area.

BACKGROUND: In Japan, the eradication rate of first-line therapy for Helicobacter pylori (H. pylori) with a proton pump inhibitor (PPI), amoxicillin (AMPC) and clarithromycin (CAM) has been decreasing because of a high prevalence of CAM resistance. A possible decrease of the eradication rate for second-line therapy with a PPI, AMPC and metronidazole (MNZ) is of concern. The aim of this study is to assess the trends in second-line eradication therapy for H. pylori in Japan. MATERIALS AND METHODS: We accumulated data retrospectively on patients administered second-line eradication therapy for Helicobacter pylori with a PPI, AMPC, and MNZ for 1 week after failure of first-line eradication therapy with a PPI, AMPC and CAM at 15 facilities in the Tokyo metropolitan area in Japan from 2007 to 2011. Trends for second-line eradication rates in modified intention-to-treat (ITT) analyses were investigated. Second-line eradication rates were categorized by three PPIs (rabeprazole (RPZ), lansoprazole (LPZ) or omeprazole (OMZ)) and evaluated. RESULTS: We accumulated data on 1373 patients. The overall second-line eradication rate was 92.4%. Second-line eradication rates in 2007, 2008, 2009, 2010 and 2011 were 97.7, 90.6, 94.5, 91.8 and 91.8%, respectively, with no significant trends revealed. Second-line eradication rates categorized by three PPIs for the entire 5-year period were 91.6, 93.4 and 92.4% (RPZ, LPZ and OPZ, respectively) with no significant differences among the three PPIs. CONCLUSIONS: From 2007 to 2011, there were no significant trends in the second-line eradication rates and the rates remained consistently high. From the viewpoint of high prevalence of CAM resistance in Japan, triple therapy with PPI, AMPC and MNZ may be a better strategy for first-line therapy compared to triple therapy with PPI, AMPC and CAM.

Endoscopic evaluation of low-dose aspirin-induced gastric and duodenal ulcers during prophylaxis with lansoprazole.

BACKGROUND/AIMS: To compare the endoscopic features of LDA-induced ulcers developing during secondary prophylaxis with lansoprazole (LPZ) and gefarnate (GFN). METHODOLOGY: All ulcers that had developed during prophylaxis with LPZ (15mg once daily) and GFN (50mg twice daily) in a prospective, randomized, double-blind trial, were reviewed and compared by a panel of expert endoscopists, based on endoscopic images available from the trial, to provide evidence for efficacy of LPZ versus GFN in secondary prophylaxis in patients with endoscopically confirmed ulcer scars. RESULTS: A total of 6 and 53 patients had developed gastric or duodenal ulcers during prophylaxis with LPZ and GFN, respectively. Six gastric ulcers seen in those given LPZ were "small" and "shallow", while, of the 38 gastric ulcers seen those given GFN, 44.7% and 55.3% were "medium" or "large" and "small", respectively. Ulcers associated with blood coagula were seen only in those given GFN. Duodenal ulcers developed in 15 and 0 patients given GFN and LPZ, respectively. CONCLUSIONS: The ulcers developing during prophylaxis with GFN and LPZ varied in their features. The study findings may be useful when devising a strategy for prophylaxis of ulcers in high-risk patients receiving LDA therapy in a routine clinical setting.

Lansoprazole for secondary prevention of gastric or duodenal ulcers associated with long-term non-steroidal anti-inflammatory drug (NSAID) therapy: results of a prospective, multicenter, double-blind, randomized, double-dummy, active-controlled trial.

BACKGROUND: Low-dose lansoprazole has not been intensively evaluated for its efficacy in the prevention of recurrent gastric or duodenal ulcers in patients receiving long-term non-steroidal anti-inflammatory drug (NSAID) therapy for pain relief in such diseases as rheumatoid arthritis, osteoarthritis, and low back pain. METHODS: This multi-center, prospective, double-blind, randomized, active-controlled study involving 99 sites in Japan was designed to compare the efficacy of lansoprazole (15 mg daily) with gefarnate (50 mg twice daily). Patients with a history of gastric or duodenal ulcers who required long-term NSAID therapy were randomized to receive lansoprazole 15 mg daily (n = 185) or gefarnate 50 mg twice daily (n = 181) and followed up for 12 months or longer prospectively. RESULTS: The cumulative incidence of gastric or duodenal ulcer at days 91, 181, and 361 from the start of the study was calculated by the Kaplan-Meier method as 3.3, 5.9, and 12.7%, respectively, in the lansoprazole group versus 18.7, 28.5, and 36.9%, respectively, in the gefarnate group. The risk for ulcer development was significantly (log-rank test, P < 0.0001) lower in the lansoprazole group than in the gefarnate group, with the hazard ratio being 0.2510 (95% CI 0.1400-0.4499). A long-term follow-up study showed an acceptable safety profile for low-dose lansoprazole therapy, with diarrhea as the most frequent adverse event. CONCLUSION: Lansoprazole was superior to gefarnate in reducing the risk of gastric or duodenal ulcer recurrence in patients with a definite history of gastric or duodenal ulcers who required long-term NSAID therapy.

Lansoprazole for secondary prevention of gastric or duodenal ulcers associated with long-term low-dose aspirin therapy: results of a prospective, multicenter, double-blind, randomized, double-dummy, active-controlled trial.

BACKGROUND: The efficacy of low-dose lansoprazole has not been established for the prevention of recurrent gastric or duodenal ulcers in those receiving long-term low-dose aspirin (LDA) for cardiovascular and cerebrovascular protection. This study sought to examine the efficacy of low-dose lansoprazole (15 mg once daily) for the secondary prevention of LDA-associated gastric or duodenal ulcers. METHODS: Patients were randomized to receive lansoprazole 15 mg daily (n = 226) or gefarnate 50 mg twice daily (n = 235) for 12 months or longer in a prospective, multicenter, double-blind, randomized active-controlled trial, followed by a 6-month follow-up study with open-label lansoprazole treatment. The study utilized 94 sites in Japan and 461 Japanese patients with a history of gastric or duodenal ulcers who required long-term LDA therapy for cardiovascular and cerebrovascular disease. RESULTS: The primary endpoint was the development of gastric or duodenal ulcers. The cumulative incidence of gastric or duodenal ulcers on days 91, 181, and 361 from the start of the study was calculated by the Kaplan-Meier method as 1.5, 2.1, and 3.7%, respectively, in the lansoprazole group versus 15.2, 24.0, and 31.7%, respectively, in the gefarnate group. The risk of ulcer development was significantly (log-rank test, P < 0.001) lower in the lansoprazole group than in the gefarnate group, with the hazard ratio being 0.099 (95% confidence interval [CI] 0.042-0.230). CONCLUSION: Lansoprazole was superior to gefarnate in reducing the risk of gastric or duodenal ulcer recurrence in patients with a definite history of gastric or duodenal ulcers who required long-term LDA therapy.

Case-control study on the association of upper gastrointestinal bleeding and nonsteroidal anti-inflammatory drugs in Japan.

OBJECTIVE: Studies in Western populations have shown the association of nonsteroidal anti-inflammatory drugs (NSAIDs) and upper gastrointestinal bleeding (UGIB). The role of Helicobacter pylori infection in NSAIDs-related UGIB remains to be studied. We conducted a case-control study in Japan to investigate these related topics. METHODS: Cases of UGIB due to duodenal or gastric ulcer, or gastritis were identified in 14 study hospitals in various areas of Japan. For each case, two controls were identified from population registries in the same district. Information on drugs and other risk factors was obtained from 175 cases and 347 controls by telephone interviews. Anti-H. pylori antibody in the urine was measured in a single laboratory for all the cases and 225 controls. RESULTS: The odds ratio (OR) of UGIB was 5.5 for aspirin and 6.1 for other NSAIDs (NANSAIDs) (p<0.01). The OR for regular use was higher than for occasional use both for aspirin (7.7 vs 2.0) and NANSAIDs (7.3 vs 4.1). Loxoprofen (5.9), frequently used in Japan as a safe 'prodrug', was significantly associated with UGIB. The odds ratio for H. pylori infection was 4.9 and the relative excess risk due to the interaction between H. pylori and the use of NSAID was 1.2 (95% CI: -5.8-8.1). CONCLUSION: NSAIDs including loxoprofen increase the risk of UGIB in Japan as in Western countries, with a similar magnitude of association. There was no evidence of biological interaction between NSAIDs and H. pylori infection.

A pilot study to evaluate a new combination therapy for gastric ulcer: Helicobacter pylori eradication therapy followed by gastroprotective treatment with rebamipide.

BACKGROUND AND AIM: Controversies remain over the need for antiulcer treatment following 1-week eradication triple therapy for Helicobacter pylori-positive peptic ulcers. The usefulness of combination therapy for gastric ulcers in Japanese patients, which consists of H. pylori eradication followed by gastroprotective therapy with rebamipide, was therefore evaluated. METHODS: The study was conducted in 52 H. pylori-positive patients with an endoscopically-proven open gastric ulcer. All patients received 1-week triple therapy (lansoprazole, amoxicillin and clarithromycin) followed by 7-week rebamipide therapy. After completion of the combination therapy, all patients underwent evaluation of ulcer healing by endoscopy, gastric ulcer symptoms and H. pylori eradication by rapid urease test and (13)C-urea breath test. RESULTS: The ulcer healing rates were 85.7% (36/42) at 8 weeks, 83.3% (30/36) in eradicated patients and 100% (6/6) in non-eradicated patients. The overall gastrointestinal symptom-free rate improved from 19.0% at baseline to 88.1% at 8 weeks. H. pylori was effectively eradicated in 85.7% (36/42) of patients. CONCLUSIONS: The results suggested that the combination therapy for open gastric ulcer was safe, well-tolerated and effective. However, data from a double-blind placebo-controlled study is necessary to confirm these findings.

Efficacy of metronidazole as second-line drug for the treatment of Helicobacter pylori Infection in the Japanese population: a multicenter study in the Tokyo Metropolitan Area.

BACKGROUND: With the increase in the frequency of clarithromycin-resistant Helicobacter pylori (H. pylori), there is rising concern about the decline of the eradication rate of this infection following treatment. The Tokyo Hp Study Group examined the eradication rate in response to a second-line regimen consisting of proton pump inhibitor (PPI), amoxicillin, and metronidazole by conducting a multicenter study in the Tokyo Metropolitan Area. MATERIALS AND METHODS: Two hundred and twenty-eight patients with H. pylori infection, in whom the first-line therapy with a PPI, amoxicillin, and clarithromycin administered for 1 week had failed to eradicate the infection, were enrolled in this study. These cases were randomly assigned to one of the two second-line regimens containing metronidazole (PPI/AM500 or PPI/AM750) administered for 1 week. 13C-urea breath test was performed as a diagnostic method test for H. pylori infection not earlier than 8 weeks after the second-line therapy. RESULTS: Intention-to-treat (ITT) and per-protocol (PP) analyses revealed an eradication rate of 87.6 and 90.6%, respectively, following PPI/AM500 treatment, and 86.9 and 88.6%, respectively, following PPI/AM750 treatment. Neither analysis revealed any significant difference in the eradication rate between PPI/AM500 and PPI/AM750 (p = .876 and .621, respectively). According to ITT and PP analyses, the eradication rates following treatment with PPI/AM500 were 85.2 and 88.5% with the use of lansoprazole, 62.5 and 62.5% with the use of omeprazole, and 93.2 and 96.5% with the use of rabeprazole, respectively. There was a significant difference in the eradication rates between PPI (omeprazole)/AM500 and PPI (rabeprazole)/AM500. In the case of PPI/AM750, the corresponding eradication rates were 84.8 and 87.0% with the use of lansoprazole, 92.9 and 92.9% with the use of omeprazole, and 92.9 and 92.9% with the use of rabeprazole, respectively. There were no significant differences in the eradication rates obtained with the use of the three PPIs. CONCLUSIONS: Both PPI/AM500 and PPI/AM750 administered for 1 week appeared to be highly effective second-line regimens for the treatment of H. pylori infection in Japanese patients. From the viewpoint of adverse events, PPI/AM500 appeared to be safe compared with PPI/AM750.

Recurrent peptic ulcers in patients following successful Helicobacter pylori eradication: a multicenter study of 4940 patients.

OBJECTIVE: Although curative treatment of Helicobacter pylori infection markedly reduces the relapse of peptic ulcers, the details of the ulcers that do recur is not well characterized. The aim of this study is to describe the recurrence rate and specific features of peptic ulcers after cure of H. pylori infection. METHODS: This was a multicenter study involving 4940 peptic ulcer patients who were H. pylori negative after successful eradication treatment and were followed for up to 48 months. The annual incidence of ulcer relapse in H. pylori-cured patients, background of patients with relapsed ulcers, time to relapse, ulcer size, and site of relapsed ulcers were investigated. RESULTS: Crude peptic ulcer recurrence rate was 3.02% (149/4940). The annual recurrence rates of gastric, duodenal and gastroduodenal ulcer were 2.3%, 1.6%, and 1.6%, respectively. Exclusion of patients who took NSAIDs led annual recurrence rates to 1.9%, 1.5% and 1.3%, respectively. The recurrence rate was significantly higher in gastric ulcer. Recurrence rates of patients who smoked, consumed alcohol, and used NSAIDs were significantly higher in those with gastric ulcer recurrence compared to duodenal ulcer recurrence (e.g. 125 of 149 [83.9%] relapsed ulcers recurred at the same or adjacent sites as the previous ulcers). CONCLUSIONS: Curative treatment of H. pylori infection is useful in preventing ulcer recurrence. Gastric ulcer is more likely to relapse than duodenal ulcer. Recurrent ulcer tended to recur at the site of the original ulcers.

Clinical significance of the accessory pancreatic duct.

BACKGROUND/AIMS: The accessory pancreatic duct is the smaller and less constant pancreatic duct in comparison with the main pancreatic duct. We investigated the patency of the accessory pancreatic duct and its role in pancreatic pathophysiology. METHODOLOGY: Dye-injection endoscopic retrograde pancreatography was performed in 411 patients. In patients in whom the main pancreatic duct could be selectively cannulated, contrast medium with indigo carmine was injected through the catheter. Excretion of the dye from the minor duodenal papilla was observed endoscopically. RESULTS: Patency of the accessory pancreatic duct was 43% of the 291 control cases. In the 46 patients with acute pancreatitis, 8 (17%) had a patent accessory pancreatic duct. The difference in patency between this group and the normal group was significant (p < 0.01). Especially, patency of the accessory pancreatic duct was only 8% of the 13 patients with acute biliary pancreatitis. In the patients with pancreaticobiliary maljunction, biliary carcinoma occurred in 72% of patients with a nonpatent accessory pancreatic duct, but in contrast, it occurred only in 30% of those with a patent accessory pancreatic duct. This difference was significant (p < 0.05). Lower amylase level in the bile of patients with pancreaticobiliary maljunction with a patent accessory pancreatic duct was frequently observed than those with a nonpatent accessory pancreatic duct. CONCLUSIONS: A patent accessory pancreatic duct may prevent acute pancreatitis by lowering the pressure in the main pancreatic duct. In cases of pancreaticobiliary maljunction with a patent accessory pancreatic duct, the incidence of carcinogenesis of the bile duct might be lower, as the reflux of the pancreatic juice to the bile duct might be reduced by the flow of the pancreatic juice into the duodenum through the accessory pancreatic duct.

[Problems occurred after Helicobacter pylori eradication and their countermeasures].

Acute esophagogastroduodenal mucosal lesions are the demonstrable adverse events occurred after H. pylori eradication. In our study, acute duodenal erosions were observed in 13.5% of the eradicated patients. Duodenal erosions which occurred mainly at the early phase after eradication were temporal and asymptomatic. Acute gastric erosion showed the same clinical manner. However, it needs to pay attention for rare occurrence of acute ulcers with severe symptoms. On the other hand, mild but persistent reflux esophagitis occurred at relatively late phase after eradication. Their occurrence rates were 9.8% after 1 year and 11.4% after 3 years. Acute mucosal lesions occurred probably due to the increase of acid output accompanied with the recovery of gastritis. Symptomatic treatment with antacids were need occasionally for acute ulcer and reflux esophagitis.

Salivary gland involvement in chronic pancreatitis of various etiologies.

OBJECTIVE: Both the pancreas and salivary glands show many histological and functional similarities. Recently, autoimmune pathogenesis has been postulated in some chronic pancreatitis cases. To examine whether a cell-mediated phenomenon involving the pancreas has a secondary effect on the salivary glands, we assessed the frequency of salivary gland dysfunction in patients with chronic pancreatitis of various etiologies. METHODS: Function of the salivary glands was examined by sialochemistry and salivary gland scintigraphy in patients with chronic pancreatitis (n = 33), Sjogren's syndrome (n = 45), and controls (n = 28). Etiologies of chronic pancreatitis were alcoholic (19 cases), idiopathic (seven cases), and autoimmune (seven cases). RESULTS: Concentrations of Na+, amylase, and beta2-microglobulin in saliva were investigated. In submandibular and parotid gland scintigraphy, time-activity curves were generated, and the ratios of peak count density and washout were calculated. Concentrations of Na+ in saliva of patients with idiopathic chronic pancreatitis and of beta2-microglobulin in saliva of patients with idiopathic and autoimmune chronic pancreatitis were significantly elevated than those of the control group. In submandibular and parotid gland scintigraphy, the peak count density ratio of patients with all chronic pancreatitis and washout ratio of patients with alcoholic and idiopathic chronic pancreatitis were significantly lower than those of the control group. CONCLUSIONS: Salivary gland function was frequently impaired in the course of chronic pancreatitis of various etiologies. Salivary gland dysfunction might be the result of a common pathophysiological effect of alcohol in patients with alcoholic chronic pancreatitis and the aggressive immune mechanism against the pancreatic and the salivary ducts in patients with autoimmune and idiopathic chronic pancreatitis.

Long-term follow-up of intraductal papillary adenoma of the pancreas.

Intraductal papillary mucinous tumors of the main pancreatic duct are often considered to be premalignant or malignant, and therefore surgical resection is recommended. We report two autopsy cases of intraductal papillary mucinous tumor of the pancreas following long-term observation. The first patient was an 84-year-old man with early gastric cancer treated by endoscopic mucosectomy. The second patient was a 77-year-old man with hepatocellular carcinoma treated by percutaneous pure ethanol injection and transarterial embolization. In both patients, endoscopic retrograde pancreatography showed a diffusely dilated main pancreatic duct, with intraductal filling defects expressing mucus, as well as dilated side branches. Obvious intramural nodules were not detected. Due to their advanced age and personal requests, both patients were managed conservatively and followed nonoperatively. In the first patient, serial pancreatograms showed progression of the pancreatic duct dilatation. Both patients died of gastric cancer, the first patient 7(1)/(2) years and the second, 10 years after first presentation, respectively. Autopsies revealed extensive intraductal papillary adenoma throughout the dilated mucus-filled main pancreatic duct. However, there was no evidence of progression to adenocarcinoma. Based on these observations, we suggest that, in patients with intraductal papillary mucinous tumor of the pancreas without obvious intramural nodules, even if the tumor is in the main pancreatic duct, pancreatectomy may not be mandatory, particularly in the elderly.

A case of solid pseudopapillary neoplasm of the pancreas and tumor doubling time.

BACKGROUND: Solid pseudopapillary neoplasm of the pancreas is a rare tumor with unique clinicopathological features. Although it is considered to grow slowly, little is known about its doubling time. METHOD: We encountered a young Japanese woman with a solid pseudopapillary neoplasm of the pancreas that had been detected at another hospital 5 years previously but was resected at our hospital. The tumor showed only a solid component without any cysts. Computed tomographic scans taken 5 years apart were compared to determine the tumor doubling time. RESULT: The tumor doubling time according to the formula of Schwartz and co-workers was determined to be 765 days. CONCLUSION: These findings confirm that this tumor grows quite slowly and also support long disease-free periods even in patients who have recurrence or metastases.

Clinical significance of a long common channel.

BACKGROUND/AIM: It was reported that in only 19 (11%) of 173 patients was the common channel at the junction of the pancreatic and bile ducts found to be 6 mm or longer. Pancreaticobiliary maljunction (PBM) is defined as an anomaly with a markedly long common channel with the junction located outside the duodenal wall, so the action of the sphincter of Oddi does not functionally affect the junction. We defined high confluence of pancreaticobiliary ducts (HCPBD) as a length of the common channel > or = 6 mm, in which the communication between the pancreatic and bile ducts was occluded when the sphincter was contracted. This study aims at investigating the clinical significance of HCPBD. METHODS: 2,980 consecutive cases with an adequate endoscopic retrograde cholangiopancreatography were reviewed. PBM and HCPBD were diagnosed according to the above definitions. PBM was divided into two groups: with or without biliary dilatation. RESULTS: PBM and HCPBD were detected in 63 (2.1%) and 50 (1.7%) cases, respectively. Biliary dilatation was detected in 30 cases having PBM. The incidences of gallbladder carcinoma associated with PBM with or without biliary dilatation and HCPBD were 13, 67, and 12%, being significantly higher than in controls (p < 0.05, p < 0.01, and p < 0.05). Pancreatic ductal reflux was detected in 11 (85%) of 13 patients with HCPBD in whom postoperative T tube cholangiograms were performed, and acute pancreatitis occurred in 14 (24%) of the 50 patients with HCPBD. CONCLUSIONS: HCPBD may be an intermediate variant of PBM. It is necessary to pay attention to an associated gallbladder carcinoma in patients with HCPBD as well as in those with PBM.