A mathematical simulation model to determine the optimal endoscopic screening strategy for detection of H. pylori-naïve gastric neoplasms.

BACKGROUND: The effectiveness of esophagogastroduodenoscopy (EGD) screening in cohorts with low Helicobacter pylori prevalence is unknown. This study aimed to develop an optimally efficient EGD screening strategy for detecting H. pylori-naïve gastric neoplasms (HpNGNs). METHODS: EGD data of 12 institutions from 2016 to 2022 were retrospectively analyzed. Age-related HpNGN prevalence, tumor growth rate, missing rate, and detection threshold size were calculated from the databases. Subsequently, using clinical data, a novel mathematical model that simultaneously simulated demographic changes and HpNGN detection was developed. Screening strategies using different starting ages (40/45/50 years) and intervals (2/5/10 years) were also compared. The detection rates of all tumors occurring within the virtual cohort and number-needed-to-test (NNT) were measured as outcomes. RESULTS: Data of 519,368 EGDs and 97 HpNGNs (34 pure signet ring cell carcinomas, 26 gastric adenocarcinomas of the fundic gland type, 30 foveolar gastric adenoma-Raspberry type, and seven undifferentiated-type cancer cases) were analyzed. A virtual cohort with a 70-year time horizon was used to simulate the occurrence, growth, and detection of 346,5836 people. Among the strategies with detection rate > 50%, the screening strategy with a 5-year interval starting at 45 years of age had the lowest NNT. Adopting this strategy, most HpNGNs were detected at < 20 mm in size, and the deep submucosal invasion rate was less than 30%. CONCLUSIONS: A mathematical simulation model revealed that screening every 5 years starting at 45 years of age could efficiently assist in identifying HpNGNs at an early stage.

Impact of preoperative tumor rupture timing on gastrointestinal stromal tumor prognosis: a retrospective multicentric cohort study.

BACKGROUND: A gastrointestinal stromal tumor rupture entails a high risk of recurrence even after curative surgery. However, the definition of rupture is unclear, and the question of whether patients with a minor rupture should be treated with adjuvant imatinib remains controversial. METHODS: The present, retrospective, multicentric study enrolled 57 patients with gastrointestinal stromal tumor with a minor/major tumor rupture, of whom 46 were finally found to be eligible for analysis. Tumor ruptures were subclassified by their degree, timing and cause. Multivariate analysis was performed to identify the risk factors of all types of recurrence as well as of peritoneal recurrence only. RESULTS: The study cohort included minor (n = 24), intraoperative (n = 19) and iatrogenic (n = 20) ruptures besides the typical types (major, preoperative and spontaneous). All intraoperative ruptures were iatrogenic. In total, 27 patients (58.7%) had a recurrence in the peritoneum (n = 17) and/or the liver (n = 13) during a median follow-up period of 5.8 years, but no recurrence was observed in patients with tumor rupture as a single, high-risk factor. Multivariate analysis found the timing of tumor rupture to be an independent risk factor of poor recurrence-free survival (hazard ratio: 2.37; 95% confidence interval: 1.02-5.49; P = 0.045). CONCLUSIONS: Preoperative tumor rupture in patients with a ruptured gastrointestinal stromal tumor was associated with poor recurrence-free survival. Our results suggested that a distinction should be made between preoperative and intraoperative tumor ruptures when considering the indications for adjuvant imatinib therapy for gastrointestinal stromal tumor patients with tumor rupture as a single, high-risk factor of recurrence.

Guidelines for endoscopic management of non-variceal upper gastrointestinal bleeding.

Japan Gastroenterological Endoscopy Society (JGES) has compiled a set of guidelines for endoscopic management of non-variceal upper gastrointestinal bleeding using evidence-based methods. The major cause of non-variceal upper gastrointestinal bleeding is peptic gastroduodenal ulcer bleeding. As a result, these guidelines mainly focus on peptic gastroduodenal ulcer bleeding, although bleeding from other causes is also overviewed. From the epidemiological aspect, in recent years in Japan, bleeding from drug-related ulcers has become predominant in comparison with bleeding from Helicobacter pylori (HP)-related ulcers, owing to an increase in the aging population and coverage of HP eradication therapy by national health insurance. As for treatment, endoscopic hemostasis, in which there are a variety of methods, is considered to be the first-line treatment for bleeding from almost all causes. It is very important to precisely evaluate the severity of the patient's condition and stabilize the patient's vital signs with intensive care for successful endoscopic hemostasis. Additionally, use of antisecretory agents is recommended to prevent rebleeding after endoscopic hemostasis, especially for gastroduodenal ulcer bleeding. Eighteen statements with evidence and recommendation levels have been made by the JGES committee of these guidelines according to evidence obtained from clinical research studies. However, some of the statements that are supported by a low level of evidence must be confirmed by further clinical research.

Initial clinical trial of a novel hemostat, TDM-621, in the endoscopic treatments of the gastric tumors.

BACKGROUND AND AIM: The feasibility of TDM-621, the synthetic infectious agent-free peptides, was tested in hemostasis of the bleeding after endoscopic treatments of the gastric tumors. METHODS: The patients who underwent endoscopic mucosal resection (EMR) or endoscopic submucosal dissection (ESD) were enrolled in the present study. The subject of hemostasis was the oozing after the EMR or ESD. The hemostatic effect, the secondary hemorrhage from one postoperative day to the day before discharge and operability were studied. RESULTS: The hemostatic effects were assessed in 12 patients. It was "remarkably effective" in 11 patients and "effective" in 1 patient. The operability was "very easy" in two patients, "easy" in eight patients and "acceptable" in two patients. No secondary hemorrhage was observed in all of 12 patients. No adverse effect considered to be related to TDM-621 was observed. CONCLUSION: It was shown that hemostasis using TDM-621 was feasible after endoscopic treatments of the gastric tumors without any technical trouble or adverse event.

Comparison of hemostasis using bipolar hemostatic forceps with hemostasis by endoscopic hemoclipping for nonvariceal upper gastrointestinal bleeding in a prospective non-randomized trial.

BACKGROUND: We previously reported on the safety and efficacy of bipolar hemostatic forceps for treating nonvariceal upper gastrointestinal (UGI) bleeding. However, no prospective or randomized studies have evaluated the efficacy of bipolar hemostatic forceps. The aim of this study was to evaluate the hemostatic efficacy of using bipolar hemostatic forceps compared with the hemostatic efficacy of the commonly used method of endoscopic hemoclipping for treating nonvariceal UGI bleeding. METHODS: A total of 50 patients who required endoscopic hemostasis for UGI bleeding were divided into two groups: those who underwent endoscopic hemostasis using bipolar hemostatic forceps (Group I) and those who underwent endoscopic hemostasis by endoscopic hemoclipping (Group II). We compared the two groups in terms of hemostasis success rate and time required to achieve hemostasis and stop recurrent bleeding. RESULTS: All (100 %) of 27 patients in Group I and 18 (78.2 %) of 23 patients in Group II were successfully treated using bipolar hemostatic forceps or by endoscopic hemoclipping alone, respectively, indicating a significantly higher success rate for Group I than for Group II (p < 0.05). The time required to achieve hemostasis was 6.8 ± 13.4 min for Group I and 15.4 ± 17.0 min for Group II. One patient in Group I (3.7 %) and four patients in Group II (22.2 %) experienced recurrent bleeding. CONCLUSION: Bipolar hemostatic forceps was more effective than endoscopic hemoclipping for treating nonvariceal UGI bleeding.

Mucosal cutting biopsy technique for histological diagnosis of suspected gastrointestinal stromal tumors of the stomach.

BACKGROUND AND AIM: The Japanese Gastrointestinal Stromal Tumor (GIST) therapeutic guidelines recommend endoscopic ultrasound-guided fine-needle aspiration biopsy for histological diagnosis. However, before 2010, this technique was only carried out at a minority of medical institutions in Japan. In the present study, we investigated the usefulness of mucosal cutting biopsy. METHODS: In 18 asymptomatic gastric submucosal tumors, mucosal cutting biopsies were carried out. We examined tumor size, tumor site (lower third: L; middle third: M; upper third: U), histopathological diagnostic yield and complications. In cases that proceeded to surgical resection with a diagnosis of GIST, we compared the pre- and postoperative histopathological diagnosis, and the histological degrees of malignancy. RESULTS: The tumors had a mean size of 20.3 mm and were located at the L site in five cases, M in four, and U in nine. Histological diagnosis of submucosal tumor was obtained in all the cases. (GIST, n = 13; heterotopic pancreas, n = 2; and leiomyoma, n = 3). No complications (e.g. bleeding, perforation or peritonitis) were seen after this procedure. In all 11 patients with GIST who underwent surgical resection, the histopathological findings from the mucosal cutting biopsy specimens were similar to those from the surgically resected specimens, with agreement between the immunostaining findings and the histological degree of malignancy (90.9%) in 10 patients. CONCLUSIONS: The mucosal cutting biopsy technique is a useful diagnostic modality for the diagnosis of gastric GIST and for selection of the appropriate treatment.

Endoscopic ultrasound-assisted rendezvous by transgastric approach in malignant extrahepatic bile duct stricture.

Endoscopic ultrasonography rendezvous (EUS-RV) is useful in cases of difficult deep biliary cannulation. However, in malignant extrahepatic bile duct strictures (MEHBDS), transduodenal routes are challenging and the transgastric approach often requires fistula dilation. We report a case of resectable MEHBDS in which transgastric puncture from the antrum of the stomach as EUS-RV was useful.

Narrow-band imaging on screening of esophageal lesions using an ultrathin transnasal endoscopy.

BACKGROUND AND AIM: Ultrathin transnasal endoscopy, used extensively in Japan, is considered to have inferior image quality and suction performance, and questionable diagnostic performance. So the aim of the present study was to compare the diagnostic performance of white light (WL) examination and non-magnified narrow-band imaging (NBI) examination in screening for esophageal disorders with ultrathin transnasal endoscopy. METHODS: A prospective case study of 105 consecutive patients screened for upper gastrointestinal disorders at a single clinic in Tokyo Medical University Hospital. All subjects were diagnosed using WL, NBI and Lugol-staining examinations. Areas ≥ 5 mm clearly not a Lugol-staining lesion were defined as esophageal disorders and the rates of detection of the two examination methods (WL vs NBI) were compared. RESULTS: For WL examination, the sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy (concordance rate) for esophageal disorders were 19.6%, 98.1%, 90.9%, 55.4%, and 59.2%, respectively, versus 60.8% 96.2%, 93.9%, 71.4%, and 78.6% for NBI. CONCLUSION: A useful level of diagnostic performance for esophageal disorders can be achieved with non-magnified narrow-band NBI ultrathin transnasal endoscopy.

[A case of pseudomembranous colitis concomitant with toxic megacolon and paralytic ileus].

A 60-year-old man was diagnosed as pseudomembranous colitis with chief complaint of fever and abdominal distension after a cerebral operation. It was ineffective although vancomycin hydrochloride (VCM) was given orally. Complications occurred. The patient had toxic megacolon and paralytic ileus. VCM was administrated via an ileus tube. In addition, the bowel was lavaged and VCM was sprayed by colonoscopy. This therapy was very effective. Generally, a patient with pseudomembranous colitis concomitant with toxic megacolon or/and paralytic ileus is considered to have a poor prognosis, however, he completely recovered by a combination of medical treatment.

Conflicting clinical environment about the management of antithrombotic agents during the periendoscopic period in Japan.

BACKGROUND AND AIMS: Although there are guidelines for the management of antithrombotic agents during the periendoscopic period, gaps between various guidelines create a confusing situation in daily clinical practice. The purpose of this study was to examine the current management of antithrombotic agents during the periendoscopic period in Japan. METHODS: This is a prospective cohort study in 12 high-volume endoscopy centers in Japan. A total of 970 outpatients receiving antithrombotic agents underwent endoscopies (705 esophagogastroduodenoscopies and 265 colonoscopies) with or without invasive procedures. Main outcome measures are adverse events in these patients. RESULTS: Need for cessation of antithrombotics before endoscopy was mostly determined by non-gastroenterologists (51%) who are unfamiliar with the Japan Gastroenterological Endoscopy Society (JGES) guideline, although cessation periods after endoscopy for most patients were determined by endoscopists (78%). Consequently, most patients underwent endoscopy without cessation (25%) or after a cessation period of 6-7 days (33%), indicating low permeation of the JGES guideline in Japan. Among 970 patients, two patients experienced major complications that may be related to thromboembolic events or gastrointestinal bleeding (95% confidence interval [CI]: 0-0.7%). One of these patients died due to sudden onset ventricular tachycardia. Invasive procedures, including 40 biopsies and two mucosal resections, were performed in 42 patients without cessation of antithrombotics, and no patients experienced major complications (95% CI: 0-8.4%). CONCLUSIONS: This study revealed a conflicting clinical environment due to absence of a unified guideline in Japan. Further accumulation of data is mandatory to establish a unified guideline based upon solid evidence.

Helicobacter pylori infection and reflux esophagitis in young and middle-aged Japanese subjects.

BACKGROUND AND AIMS: Helicobacter pylori infection rates are reported to be high in people over the age of 40 years, but are decreasing in younger age groups. A negative correlation has been reported between H. pylori infection and reflux esophagitis (RE). METHODS: The subjects were 418 patients who underwent esophagogastroduodenoscopy and measurement of serum immunoglobulin G H. pylori antibodies examined as part of their routine health checks. Their mean age was 39.2 +/- 8.3 years (range 22-58). We analyzed the RE findings (Los Angeles classification: A, B, C, D). RESULTS: The total H. pylori infection rate was 33.7% (141/418). By age group, infection rates were 15.7% in the 20-29 years group, 28.0% in the 30-39 group, 34.3% in the 40-49 group and 69.1% in the 50-59 group. The proportion of H. pylori-negative subjects with RE was 23.5% (20-29, 22.9%; 30-39, 31.7%; 40-49, 32.4%; 50-59, 41.7%), significantly higher than that (12.1%) in H. pylori-positive subjects (20-29, 0%; 30-39, 16.7%; 40-49, 12.2%; 50-59, 10.5%). The severity of RE increased with advancing age in H. pylori-positive subjects, but not in H. pylori-negative subjects. CONCLUSION: In this study, higher rates of RE were seen in H. pylori-negative subjects. It may be, however, that the presence of H. pylori infection influences the progression of RE.

Clinical evaluation of emergency endoscopic hemostasis with bipolar forceps in non-variceal upper gastrointestinal bleeding.

The present study was designed to evaluate the usefulness and safety of bipolar hemostatic forceps, known as a less invasive and highly safe means of thermal coagulation used for hemostasis in cases of non-variceal upper gastrointestinal bleeding. This technique of bipolar forceps is simple, safe and unlikely to induce complications, and is therefore promising as a new technique of endoscopic hemostasis. The study involved 39 cases where hemostasis was attempted with bipolar forceps to deal with non-variceal upper gastrointestinal bleeding, including 28 cases of gastric ulcer, six cases of duodenal ulcer, three cases of bleeding after endoscopic submucosal dissection (ESD), one case of Mallory-Weiss syndrome and one case of postoperative bleeding from the anastomosed area. There were 34 males and five females, with a mean age of 63.6 years. Bipolar forceps were the first-line means of hemostasis in cases of oozing bleeding (venous bleeding), pulsatile or spurting bleeding (arterial bleeding) and exposed vessels without active bleeding. The primary hemostasis success rate was 92.3%, and the re-bleeding rate was 0%. In cases where the bleeding site was located along the tangential line or in cases where large respiration-caused motions hampered identification of the bleeding site, hemostasis by means of coagulation was easily effected by application of electricity while the forceps were kept open and compressed the bleeding area. In addition, there were no complications. This technique of bipolar forceps is simple, safe and unlikely to induce complications, and is therefore promising as a new technique of endoscopic hemostasis.

Complete remission of peritoneal dissemination of colon cancer by alternate-day S-1 and oxaliplatin plus bevacizumab treatment and maintenance chemotherapy comprising alternate-day S-1 plus bevacizumab: A case report.

A 56-year-old man diagnosed with sigmoid colon cancer underwent sigmoid colectomy. Nine months later, his serum carcinoembryonic antigen (CEA) level had increased, and the diagnosis of recurrent peritoneal dissemination was made based on positron emission tomography/computed tomography (PET/CT) findings. Although systemic chemotherapy comprising S-1 and oxaliplatin (SOX) plus bevacizumab was initiated, severe diarrhea occurred on day 4 of the second cycle despite reduction in S-1 dose. By changing the daily oral intake schedule for S-1 to an alternate-day intake from the third cycle (modified SOX plus bevacizumab), the patient was able to continue undergoing chemotherapy without any adverse gastrointestinal effects. All tumors disappeared after four cycles, and the patients received eight cycles of modified SOX plus bevacizumab followed by maintenance chemotherapy comprising alternate-day S-1 plus bevacizumab. Maintenance chemotherapy was discontinued after 17 cycles owing to adverse events, including thrombocytopenia, corneal and lacrimal duct disorders, and hyperbilirubinemia. The patient has been radiographically confirmed to be in remission for 5 years without any recurrence, and his serum CEA level has been within normal range for >3 years. To conclude, compared with the conventional consecutive treatment, alternate-day SOX plus bevacizumab treatment may reduce the adverse effects of these chemotherapeutic drugs.

Tailored eradication therapy based on fecal Helicobacter pylori clarithromycin sensitivities.

BACKGROUND AND AIM: Helicobacter pylori (H. pylori) eradication rates using the PPI/AC regimen (proton pump inhibitor + amoxicillin + clarithromycin) are declining. We trialed tailoring eradication regimens according to clarithromycin (CAM) susceptibility. METHODS: The subjects were 70 H. pylori positive adults. They were randomly allocated to a tailored group and a control group. In the tailored group, subjects with CAM-sensitive strains were given PPI/AC eradication therapy, and those with CAM-resistant strains were given PPI/AM (metronidazole instead of clarithromycin) therapy. The control group were all given PPI/AC therapy. CAM sensitivity was measured by collecting fecal specimens, and extracting the DNA. The 23S rRNA domain, associated with CAM susceptibility in H. pylori, was amplified using a nested polymerase chain reaction (PCR), and DNA sequencing was used to detect point mutations at A2143G and A2144G. RESULTS: Eradication rates were 94.3% in the tailored group and 71.4% in the control group. In particular, the eradication rate was 100% for CAM-resistant strains in the tailored group. CONCLUSIONS: In Japan, where CAM-resistant H. pylori strains are expected to continue to increase, tailored eradication therapy according to CAM sensitivity will be of benefit.

Impact of transnasal ultrathin esophagogastroduodenoscopy (UT-EGD) in the evaluation of esophageal peristaltic function.

BACKGROUND: We used transnasal ultrathin esophagogastroduodenoscopy (UT-EGD) to simultaneously perform realtime esophageal manometry and observe esophageal peristalsis. METHODS: The subjects were 22 healthy volunteers and 10 patients with proton-pump inhibitor (PPI) dependent gastroesophageal reflux disease (GERD). We induced the primary peristaltic wave associated with swallowing and observed it endoscopically in the lower esophagus, at the same time measuring the intraesophageal pressure using a manometry catheter. RESULTS: The mean primary peristaltic amplitude associated with swallowing was 65.6+/-47.4 mmHg in the volunteer group, and 28.0+/-25.6 mmHg in the GERD group. Although peristalsis was observed endoscopically in the GERD group, in some cases incomplete peristalsis left a small but definite lumen and in these subjects, the primary peristaltic wave was almost flat. CONCLUSIONS: The use of an ultrathin transnasal endoscope makes possible simultaneous manometry and endoscopic observation of the esophagus. This combination should prove useful in the evaluation of esophageal peristaltic function, such as in the diagnosing of GERD.

A study of the relationship between Helicobacter pylori microbial susceptibility, 13C-urea breath test values.

BACKGROUND/AIMS: Diagnostic methods for Helicobacter pylori (H. pylori) infection can be divided into invasive endoscopic methods and non-invasive methods. A typical and widely used non-invasive method is the 13C urea breath test (UBT). In this study, the possibility of a correlation between pre-treatment UBT values with H. pylori antimicrobial resistance is investigated. METHODOLOGY: The subjects were 119 consecutive patients who attended this hospital for H. pylori testing. Average age was 47.5 +/- 13.2 years, with a male:female ratio of 2.05:1. The diagnosis was gastric ulcer in 43 subjects, duodenal ulcer in 27, gastroduodenal ulcer in 21 and chronic gastritis in 28. Subjects underwent UBT as well as upper gastrointestinal endoscopy (UGITE). The diagnosis of H. pylori infection was examined by the results of culture, histological examination and the rapid urease test (RUT). The mean inhibitory concentration (MIC) was determined for each antimicrobial agent in the bacterial isolates that could be cultured. RESULTS: In this study, the sensitivity and specificity were excellent at 97.0% and 100% with a cut-off point of 3.5 per thousand for UBT respectively. Clarithromycin resistance was more common in the group with high UBT values. No correlation at all was seen between UBT values and metronidazole, sparafloxacin, cefaclor and amoxicillin susceptibility. CONCLUSIONS: It is possible that UBT values also tend to be higher in cases of CAM resistance.

Comparison of the effects on cardiopulmonary function of ultrathin transnasal versus normal diameter transoral esophagogastroduodenoscopy in Japan.

BACKGROUND/AIMS: Transnasal esophagogastroduodenoscopy (EGD) is reported to be more pleasant than conventional transoral EGD. In this study, we compared the hemodynamic effects of transnasal and transoral EGD. METHODOLOGY: The subjects were 120 patients with upper gastrointestinal conditions. Transnasal and transoral EGD were performed on 60 subjects each. Oxygen saturation, heart rate and blood pressure were monitored. Subjects were also asked for their condition with each EGD. RESULTS: VAS scores for discomfort at the insertion, and for trouble breathing and nausea during the procedure, were significantly lower for transnasal than for transoral EGD. A significant increase in the heart rate and significant decrease in oxygen saturation were seen only in the transoral group during EGD. The double product (heart rate x systolic blood pressure) was also significantly increased only in the transoral group. No significant changes were seen in the transnasal EGD. CONCLUSIONS: Double product has been reported to correlate with myocardial oxygen consumption. Transnasal EGD is a safe technique, and is not only less stressful to patients, but also has fewer hemodynamic effects than the transoral method.

[The efficacy of gastrojejunostomy for patients with unresectable gastric cancer].

We evaluated the efficacy of gastrojejunostomy for patients with unresectable gastric cancer. Thirteen patients had undergone gastrojejunostomy (GJ group) and 14 patients who couldn't receive gastrojejunostomy, but had only been observed into their abdomen in the operation (S group). Between two groups, there were no significant differences in the effective rate, median survival time and the number of dates the patient stayed home after the operation. Gastrojejunostomy was useful for patients with a strong case of stenosis in the stomach, and may improve the quality of life as one of the multimodal therapy.

Efficacy of short period, low dose oral prednisolone for the prevention of stricture after circumferential endoscopic submucosal dissection (ESD) for esophageal cancer.

BACKGROUND AND AIMS: Endoscopic submucosal dissection (ESD) was developed in Japan and has been performed on many patients with early stage esophageal cancer; however quality of life in patients with postoperative stricture is drastically decreased and repeat, periodic endoscopic balloon dilatation (EBD) is usually required over long periods. In this study, we evaluate the efficacy of short period, low dose oral prednisolone in controlling post-procedural esophageal stricture. PATIENTS AND METHODS: In total, 33 patients who underwent semicircular or complete circular ESD for esophageal superficial squamous cell carcinoma were included in this study. They were divided into two groups: those who underwent large-circumference ESD with no preventative treatment for stricture (ESD alone group) and those who received systemic steroid treatment for stricture (oral prednisolone group). We compared the two groups in terms of stricture rate and total number of EBD sessions. The ESD alone group underwent no preventative treatment. The oral prednisolone group started with 30 mg/day prednisolone on the second day post-ESD, and continued with a gradually tapering prednisolone dose, finally discontinuing systemic steroid administration 3 weeks later. RESULTS: The stricture rate after ESD was significantly lower in the oral prednisolone group (3 of 17 patients; 17.6 %) than in the ESD alone group (11 of 16 patients; 68.7 %) (P < 0.01). The number of EBD sessions was significantly lower in the oral prednisolone group than in the ESD alone group (median 4.6, range 2 - 10 vs. median 8.1, range 1 - 18; P < 0.01). CONCLUSION: Short period, low dose oral prednisolone showed promising results for the prevention of stricture after ESD for early stage esophageal cancers.

Clinicopathological characteristic and clinical handling of the patients with 2 cm or less gastric GISTs.

BACKGROUND: We previously reported that safety and efficacy of mucosal cutting biopsy for diagnosing included 2 cm or less gastric GISTs. However, there have been no reports stating the clinicopathological characteristic and clinical handling of the patients with 2 cm or less gastric GISTs. The aim of our study is to investigate the clinicopathological characteristic and clinical handling of the patients with 2 cm or less gastric GISTs. METHODS: The 19 patients diagnosed with GIST by mucosal cutting biopsy were divided into 2 groups: Group I; subjects were GISTs with 2 cm or less, Group II; subjects were GISTs >2 cm. We compared the 2 groups in terms of mean age, tumor size, tumor site, histopathological risk grade. In cases that underwent surgery with a diagnosis of GIST, we compared the pre- and postoperative histopathological diagnosis, and the histopathlogical risk grade within each group. RESULTS: The mean age and tumor size were significantly higher in Group I than in Group II. Meanwhile, there were no significant differences between the 2 groups, sex ratio, tumor site. All lesions were at histopathological risk grade at very low risk and low risk respectively. In 17 patients with GIST who underwent surgery, the histopathological diagnoses, immunostaining were in agreement with those from the mucosal cutting biopsy specimens in all cases, but mitotic count of one patient was not in agreement in group II. CONCLUSIONS: The 2 cm or less gastric GISTs diagnosed with histpathlogical very low risk can be considered acceptable to follow-up.