Incidence of metachronous gastric cancer in patients whose primary gastric neoplasms were discovered after Helicobacter pylori eradication.

BACKGROUND AND AIMS: The incidence of metachronous gastric cancer (MGC) in patients whose primary gastric neoplasm is discovered after Helicobacter pylori eradication remains unclear. Here, we evaluated the long-term effect of previous H pylori eradication on development of MGC after endoscopic submucosal dissection (ESD). METHODS: We analyzed prospectively collected data of consecutive patients with successful H pylori eradication more than 1 year before (eradicated group, 180 patients) or after (control group, 602 patients) initial curative ESD. These patients were also followed by endoscopy for over 2 years. Propensity score matching and inverse probability of treatment weighting (IPTW) were used to adjust for confounding variables during data analysis. The main outcome was the incidence of MGC after initial ESD. RESULTS: In a propensity-matched analysis of 174 pairs, the incidence of MGC was similar in the 2 cohorts (33.9 per 1000 person-years vs 40.8 per 1000 person-years in the control group, P = .454) at a median follow-up of 4.1 years (interquartile range, 3.0-5.6). Incidences were also similar in the 2 groups when data were analyzed using IPTW, even after exclusion of 123 patients with successful H pylori eradication <5 years before initial ESD. Multiple Cox regression analysis revealed age, differentiated-type histology, and initial multiplicity were predictors of MGC in patients after initial curative ESD. CONCLUSIONS: The frequency of follow-up surveillance after initial curative ESD should be kept constant, irrespective of whether H pylori eradication is performed before or after initial curative ESD.

Comparison of diagnostic accuracies of various endoscopic examination techniques for evaluating the invasion depth of colorectal tumors.

This study was designed to assess the clinical value of magnifying endoscopy combined with EUS for estimating the invasion depth of colorectal tumors. We studied 168 colorectal adenomas and carcinomas that were sequentially examined by conventional endoscopy followed by magnifying endoscopy and EUS in the same session to evaluate invasion depth. Endoscopic images obtained by each technique were reassessed by 3 endoscopists to determine whether endoscopic resection (adenoma, mucosal cancer, or submucosal cancer with slight invasion) or colectomy (submucosal cancer with massive invasion or advanced cancer) was indicated. The accuracy of differential diagnosis was compared among the examination techniques. The rate of correct differential diagnosis according to endoscopic examination technique was similar. The proportion of lesions that were difficult to diagnose was significantly higher for EUS (15.5%) than for conventional endoscopy and magnifying endoscopy. Among lesions that could be diagnosed, the rate of correct differential diagnosis was the highest for EUS (89.4%), but did not significantly differ among three endoscopic examination techniques. When it is difficult to evaluate the invasion depth of colorectal tumors on conventional endoscopy alone, the combined use of different examination techniques such as EUS may enhance diagnostic accuracy in some lesions.

Rectal granular-cell tumor difficult to distinguish from carcinoid tumor.

A 60-year-old man had a positive fecal occult-blood test on a medical check-up. Colonoscopy revealed a yellowish-white submucosal tumor 8 mm in diameter in the rectum. Endoscopic ultrasonography showed a well-demarcated mass with a homogeneous, low-level, internal echo in the second to third layers of the rectal wall. A carcinoid tumor was suspected, and the mass was resected endoscopically. Histopathological examination revealed a granular-cell tumor. Gastrointestinal granular-cell tumors rarely arise in the rectum, and the preoperative diagnosis of small lesions is often difficult. In our patient, granular-cell tumor was difficult to differentially diagnose because the endoscopic and endoscopic ultrasonographic findings closely resembled those of carcinoid tumor. Interestingly, the endoscopic characteristics of the rectal granular-cell tumor in our patient resembled those of a carcinoid tumor.

[Single-balloon enteroscopy].

Double-balloon enteroscope (DBE) requires a long preparation time and scope insertion is often confused because balloons have to be attached to both the endoscope and the overtube. Single-balloon enteroscope (SBE) is a new model endoscope produced by Olympus Medical Systems, and SBE does not require a balloon to be attached to the scope and has only sliding tube. Therefore, examination, preparations and scope insertion are easier than with DBE. SBE provides high-quality 'Q' type endoscopic images, and narrow-band-imaging can be performed. A prototype ultrasonic probe for SBE is now available. We underwent enteroscopy with SBE in 40 patients, and the total number of sessions was 50. Total enteroscopy was possible in 3 of 5 patients, in whom SBE was inserted deeply through both mouth and anus. There were no serious complications. This newly developed enteroscopy is useful for the diagnosis and treatment of small intestinal bleeding, intestinal stricture and protruding lesions. We believe that the single-balloon enteroscope will be more widely used clinically in the near future.