In Japan, population-based colorectal cancer screening began in 1992, and the Japanese Society of Gastrointestinal Cancer Screening also began implementing many studies on colorectal cancer screening in 1982. Nevertheless, the number of deaths from colorectal cancer has increased tenfold or more, i. e., from 4,822 (1958) to 50,658 (2018), an increase of 45,836. Colorectal cancer primarily has a good prognosis, and if diagnosed in the preclinical stage, before the presence of any symptoms, or at least by stage III, majority of patients are likely to survive. The present colorectal cancer screening protocol, which uses the fecal occult blood test, has been verified to reduce the mortality rate of colorectal cancer, and if the accuracy of colorectal cancer screening is properly achieved, the number of colorectal cancer deaths can be reduced. Hence, the number of colorectal cancer deaths can unequivocally decrease if the present proposal for colorectal cancer screening is implemented as follows: 1) annual fecal immunochemical test (FIT), 2) FIT for at least five consecutive years, 3) total colonoscopy (TCS) for 100% of FIT positive results, and 4) TCS as "milestone screening" for people who have not had TCS before 50 years old.

Objective: This study was conducted to determine the degree of endoscopic gastric mucosal atrophy (GMA) in different generations with Helicobacter pylori (H. pylori) infection.

Methods: We examined 1,224 subjects (763 males, 461 females; mean age 52.2 years) who were diagnosed as positive for H. pylori infection by both endoscopic findings and serum anti-H. pylori IgG antibody test. The degree of endoscopic GMA was classified using the Kimura-Takemoto classification of mucosal atrophy in the stomach.

Results: The degree of GMA was increased in association with aging. However, approximately one-fourth of the subjects aged over 60 years showed mild GMA, of whom some were endoscopically diagnosed as nodular gastritis. Furthermore, two different peaks were observed for the distribution of degree of GMA in male and female subjects aged over 60 years.

Conclusion: The degree of GMA increases with aging in cases of H. pylori infection. However, the initiation of H. pylori infection in some patients can occur after the childhood period.

Objective: This study aimed to evaluate of diagnostic accuracy of the new latex-based anti-Helicobacter pylori (H. pylori) IgG measurement kits: LZ test "Eiken" H. pylori antibody (Eiken-L) and L-type Wako H. pylori antibody J (Wako-L).

Methods: Serum of 899 healthy examinees were used. E-plate "Eiken" H. pylori antibody II (E-plate3 with a cutoff of 3 U/ml) was used as standard control.

Results: Sensitivity, specificity, and false-negative rate based on infection diagnosis of H. pylori by endoscopy were 84.7%/97.0%/15.3% for E-plate3. Concerning Eiken-L compared with E-plate3, sensitivity (68.5%) was significantly lower; specificity (98.2%) was almost equal, and false-negative rate (31.5%) was significantly higher. Concerning Wako-L compared with E-plate3, specificity (92.6%) was significantly lower; sensitivity (83.8%) and false-negative rate (16.2%) were almost equal. As for the prevalence of "pseudo-A" group in ABC risk stratification for gastric cancer, Eiken-L (27.9%) was significantly higher than E-plate 3 (13.5%), whereas Wako-L (14.4%) showed no significant difference from E-plate3.

Conclusion: Based on infection diagnosis of H. pylori by endoscopy, sensitivity of Eiken-L was significantly lower than that of E-plate3, whereas false-negative rate and "pseudo-A" group rate of Eiken-L were significantly higher than those of E-plate3. There were no significant differences in sensitivity, false-negative rate, and "pseudo-A" group rate between Wako-L and E-plate3.

Overexposure of the esophagus to gastric acid due to gastroesophageal reflux is the main cause of esophageal mucosal damage in reflux esophagitis. Various factors of reflux esophagitis have been considered, including obesity. However, the effect of qualitative visceral fat on reflux esophagitis in metabolic syndrome (MS) is unclear. In this study, we investigated the relationship between reflux esophagitis and qualitative visceral fat in people with MS.

Of the 43,262 people who underwent medical examinations, 875 people with MS who had upper gastrointestinal endoscopic examinations were included; patients taking gastric acid secretion inhibitors were excluded. The incidence of reflux esophagitis was 17.7% (visceral MS: 23.8% > subcutaneous MS: 12.3%). In multivariate analysis, alcohol consumption, Helicobacter pylori (H. pylori), esophageal hiatal hernia, and visceral MS were significant factors for the onset of reflux esophagitis.

Alcohol consumption, esophageal hiatal hernia, negative for H. pylori, and visceral MS are important factors for the onset of reflux esophagitis in people with MS. Hence, it is necessary to consider the qualitative assessment of visceral fat, besides MS diagnosis, in medical examinations, considering the differences in the clinical background and incidence of reflux esophagitis depending on whether the person has visceral MS or subcutaneous MS.

Aim: We investigated diagnostic abilities of non-biopsy tests for autoimmune gastritis (AIG).

Methods: Patients with suspected AIG without biopsy information were retrospectively recruited in JCHO Shiga Hospital from May 2012 to April 2017. They were suspected with positive anti-parietal cell antibody (PCA) test and at least one of the following 4 tests: high serum gastrin concentration, severe endoscopic gastric mucosal atrophy (Nakajima's criteria O-p), 3+pepsinogen test, and low serum vitamin B₁₂ concentration. Helicobacter pylori (H. pylori) infection was evaluated using two or more H. pylori tests. Those who underwent biopsy using stomach samples were further investigated. Biopsy specimens taken from greater curvature of middle corpus were histologically evaluated for atrophy using the updated Sydney system. The aforementioned 4 non-biopsy tests were assessed using biopsy-based histological evaluation.

Results: Twenty-one patients were suspected of AIG without pathological information. Of these, one was diagnosed with active H. pylori infection but not AIG. Therefore, 20 patients were diagnosed with suspected AIG and further investigated. Biopsy-based histology was evaluated in 15 subjects; AIG was confirmed in these patients. Of these subjects, all 15 patients had high serum gastrin concentration, 14 had endoscopic O-p atrophy, 11 were positive for the 3+pepsinogen test, and 9 had low vitamin B₁₂ levels; these subjects showed severe histological fundic gland atrophy.

Conclusion: High serum gastrin concentration, endoscopic O-p atrophy, 3+pepsinogen test, and low vitamin B₁₂ concentration were effective indirect markers of severe fundic gland atrophy in patients with suspected AIG. If PCA is positive and H. pylori infection is negative, at least one positive result of these 4 tests is acceptable for the primary diagnosis of AIG without performing biopsy.

A 60-year-old woman who was found to have a protruding lesion in the stomach via a X-ray checkup and a detailed esophagogastroduodenoscopy consulted to our hospital to be further examined and treated. The lesion located at the greater curvature of the middle gastric body was a pedunculated polypoid lesion accompanied by a small mucosal defect of 2 cm in diameter. The pathological diagnosis by a forceps biopsy specimen obtained from a mucosal defect is categorized as Group 1. The endoscopic ultrasonography conducted in our hospital revealed the multicystic form of submucosal layer in the lesion. These morphological characteristics indicated that the lesion could be diagnosed as a pedunculated hamartomatous inverted polyp (HIP). Upon hearing her medical history of annual checkup and endoscopic examinations, this lesion was first detected as a small normal-colored polyp of 1 cm in diameter suspected to be an HIP via a health checkup 11 years ago. Through follow-up via health checkups, the HIP showed gradual enlargement and then exhibited expanded head accompanied by an elongated stalk of 2 cm in diameter 3 years ago. One year ago, the polyp did not show remarkable change, so she was recommended to be followed up via a health checkup. This time, she consented to receive the endoscopic polypectomy, because the HIP showed a gradual enlargement and has a slightly potential risk of gastric cancer development. The specimens of resected lesion revealed the submucosal tumor covered with normal surface epithelium. The polyp comprised submucosal invasion of cystic gastric glands accompanied by fibromuscular elements; these pathological findings indicate the definite HIP diagnosis.

We encountered four cases of colorectal cancer in young adults (aged <40 years) with positive fecal occult blood test during optional colorectal cancer screening. Three patients were male, and all patients were aged in their 30s. Two patients used to smoke, three had a history of drinking alcohol, and one had a family history of pancreatic cancer. Body mass index of each patient was <25 kg/m². The tumor was found in the right colon in two cases and sigmoid colon and rectum in the other two cases. Three patients received endoscopic treatment, and one underwent surgery. In the pathological examination, two patients had early cancer, and the others had advanced cancer. All patients had good clinical courses without recurrence and/or metastasis. However, the clinical significance of colorectal cancer in young adults aged <40 years was not negligible, because 2 of the 4 patients had advanced cancer. The epidemiology of colorectal cancer in young adults remains unknown. To detect colorectal cancer as early as possible and reduce cancer mortality as much as possible, the first step is to understand its epidemiology, and the second step is to identify risk factors related to the disease.