ABC Classification Is Less Useful for Older Koreans Born before 1960

Helicobacter pylori Infection Status and Gastric Tumor Incidence According to the Year of Birth

Background/Aims

: The prevalence of Helicobacter pylori-naive status is increasing. Nonetheless, biennial gastroscopy is recommended for all Koreans aged 40 to 75 years. This study aimed to determine whether gastric cancer screening guidelines could be changed according to H. pylori infection status and year of birth.

Methods

: Koreans who underwent serum assays and gastroscopy for gastric cancer screening between 2010 and 2016 were included if screening tests were followed up for ≥3 times. H. pylori infection was confirmed when invasive tests or 13C-urea breath tests were positive. In the case of negative test findings, eradication history, serologically detected atrophy, and intestinal metaplasia/atrophy were checked for past infection. If all were absent, H. pylori-naive status was confirmed.

Results

: Two-thousand and two (256 H. pylori-naive, 743 past-infected, and 1,003 infected) Koreans underwent screening tests for 95.5±28.4 months. The mean year of birth in the naive group (1969±7) differed from those of the past-infected (1957±10, p<0.001) and infected (1958±10, p<0.001) groups. H. pylori-naive status was correlated with recent year of birth (r=0.368, p<0.001). No gastric tumors were observed among the naive participants (p=0.007), whereas 23 adenomas, 18 adenocarcinomas, and two neuroendocrine tumors were detected in 1.9% (14/743) of past-infected and 2.5% (25/1,003) of infected participants, including four infected participants with metachronous tumors.

Conclusions

: The prevalence of H. pylori-naive status is increasing in young Koreans, and gastric tumors are rare in this population. Hence, biennial gastroscopy could be waived after the confirmation of naive status.

Population-based X-ray gastric cancer screening in Hiroshima prefecture, Japan

BACKGROUND

X-ray gastric cancer (GC) screening has been shown to decrease mortality. Population-based X-ray GC screening has been performed in Hiroshima Prefecture, Japan, since 1983 but time trends and the efficacy of the method over 39 years have not been assessed.

AIM

To evaluate time trends and efficacy of population-based X-ray GC screening and identify challenges and suggested solutions for the future.

METHODS

This was a population-based retrospective study. The data were derived from aggregated data of the Hiroshima Regional Health Medical Promotion Organization, including the number and rate of participants and those requiring esophagogastroduodenoscopies (EGDs), the number and rate of participants diagnosed as having GC, and the positive predictive value of the abnormal findings detected by X-ray and confirmed by EGDs. The number and rate of esophageal cancers were also collected. Further, the cost of detecting one GC was evaluated.

RESULTS

The number of participants has decreased during the last four decades, from 39925 in 1983 to 12923 in 2021. The rate of those requiring EGDs decreased significantly in recent years (P < 0.001). The number of participants diagnosed as having GC has also declined, from 76 to 10 cases. However, the rate of cases diagnosed as GC among the participants remained around 0.1%. The positive predictive value increased significantly in recent years except during 1983-1991. The number and rate of accidentally detected esophageal cancers have risen recently, from 0% in 2008 to 0.02% in 2021, one-fifth of the diagnosis rate of GC. One GC diagnosis costs approximately 4200000 Japanese Yen (30000 United States Dollars) for the X-ray screenings and EGDs.

CONCLUSION

X-ray GC screening in Hiroshima has been efficient, but one challenge is the cost. Esophageal cancers may also need to be considered because they have gradually increased in recent years.

Useful Serum Pepsinogen Levels for Detecting Ongoing Helicobacter pylori Infection in Asymptomatic Subjects: A Cross-Sectional Study Based on 13C-urea Breath Test Findings

BACKGROUND /AIMS

The serum pepsinogen (PG) assay is used to screen subjects at high risk for gastric cancer. Currently, there are few studies on the PG levels for the detection of Helicobacter pylori infection. This study aimed to determine the PG assay findings for detecting ongoing infection.

METHODS

Asymptomatic subjects who underwent a ¹³C-urea breath test (¹³C-UBT) on the day of gastroscopy and serum assay for cancer screening were included. Subjects with a recent intake of acid suppressants or antibiotics, gastrectomy, or renal failure were excluded. H. pylori infection was defined as a positive ¹³C-UBT result.

RESULTS

Among the 500 included subjects, 167 (33.4%) had current infection. The serum PG II levels of > 12.95 ng/mL (area under the curve [AUC] = 0.930, sensitivity 86.5%, specificity 90.7%) and PG I/II ratios of < 4.35 (AUC = 0.875, sensitivity 86.8%, specificity 79.6%) were related to infection. The PG I/II ratios were inversely correlated with age (r = -0.160, p = 0.039). The cutoff values of PG I/II ratios were lower in older subjects aged ≥ 50 years (< 4.05; AUC = 0.875, sensitivity 80.7%, specificity 88.2%) than in younger subjects aged < 50 years (< 4.35; AUC = 0.873, sensitivity 77.4%, specificity 88.9%).

CONCLUSIONS

Serum PG II levels > 12.95 ng/mL and PG I/II ratios < 4.35 suggest ongoing infection in asymptomatic subjects; therefore, H. pylori confirmation tests (i.e., ¹³C-UBT) should be considered under these conditions. Stricter criteria are required in older subjects aged ≥ 50 years (PG I/II ratio < 4.05) to detect ongoing infection than younger subjects.

Prognosis of Seronegative Subjects with a Helicobacter pylori-infected Spouse

Background/Aims: Helicobacter pylori (H. pylori) can disseminate between couples. The present study compared the findings of gastric cancer screening between seronegative subjects according to the presence of an infected spouse.Materials and Methods: Follow-up data of seronegative subjects were analyzed among married couples who underwent gastric cancer screening via gastroscopy, serum pepsinogen, and anti-H. pylori IgG assays between January 2010 and May 2016. New detection rates of H. pylori infection and gastric neoplasm at the follow-up screening were compared between seronegative subjects according to the H. pylori-infected status of spouse.Results: Among 246 seronegative subjects with an H. pylori-infected spouse, 92 underwent follow-up tests (case group). Among 278 seronegative subjects with seronegative spouse, 94 underwent follow-up tests (control group). The past infection rate was higher in the case group than in the control group (52/92 vs. 34/94; P=0.005). New H. pylori infection was diagnosed in three of the 92 cases and two of the 94 controls (3.2% vs. 2.1%; P=0.681). During the mean follow-up of 67.9±36.0 months, three adenocarcinomas and two adenomas (5/184) were newly detected among the cases and their spouses, whereas none (0/188) were detected among the controls and their spouses (2.7% vs. 0%; P=0.029).Conclusions: Gastric neoplasm occurred more frequently in couples with an H. pylori-infected spouse. Because the past infection rate is higher among seronegative subjects with an infected spouse, gastric cancer screening is recommended in both partners when the spouse is infected.

Serum Assay Findings after Successful Helicobacter pylori Eradication

Serum pepsinogen (PG), anti-Helicobacter pylori (H. pylori) immunoglobulin G (IgG), and gastrin-17 (G-17) are plasma biomarkers for gastritis. H. pylori serology titers and PG levels increase during active H. pylori infection; moreover, elevated PG II levels indicate a high risk for diffuse-type gastric cancer in East Asian populations. Serum PG I/II ratios and PG I levels decrease with the progression of gastric corpus atrophy; thus, a combination of serum PG I levels ≤70 ng/mL and a PG I/II ratio ≤3 (serologic atrophy) indicates a high risk of intestinal-type gastric cancer. Serum G-17 is often not used as an indicator in H. pylori-seroprevalent populations because it is usually elevated in subjects with H. pylori infections. When H. pylori is eradicated, most patients show a rapid decrease in serum PG II levels and anti-H. pylori IgG titers within a few months. Seroreversion is required for several months to years after regression of H. pylori. Moreover, seroreversion may not always be achieved in all eradicated cases. The serum PG I/II ratio starts to increase after eradication; therefore, serologic atrophy improves accordingly, unless severe atrophy is present. Thus, some eradicated patients may show normal serum assay findings but have a higher risk for developing gastric cancer than H. pylori-naive subjects. Furthermore, serum PG levels decrease after gastrectomy and increase with the intake of certain drugs (e.g., aspirin or acid suppressants) or in renal failure patients. Due to such wide variations, serum assays are inadequate for the confirmation of H. pylori eradication. It is useful when interpreted with gastroscopy and other H. pylori test findings.

Scoring model for discriminating gastric cancer risk in patients with negative serum pepsinogen and anti-Helicobacter pylori antibody results

BACKGROUND

The ABC test measures serum pepsinogen and anti-Helicobacter pylori IgG antibody levels to predict precancerous conditions in the stomach and gastric cancer. However, a limitation of this test is that the gastric cancer risk is not negligible in patients with a negative result.

METHODS

Based on their ABC results, 1157 patients were classified into Groups A (n = 392), B (n = 479), C (n = 247), and D (n = 39). In Group A, 24.2% of patients had atrophic gastritis and/or intestinal metaplasia and had thus been incorrectly assigned to Group A. Patients in Group A were then assigned to derivation (n = 236) and validation (n = 156) cohorts by 3:2 random sampling. Logistic regression analyses were performed to identify the factors discriminating between a correct (true) and incorrect (false) Group A classification.

RESULTS

A 4-point discriminative model was constructed based on a high-negative H. pylori IgG antibody titer and the patient's age (50-64 and ≥65 years). The areas under the receiver operating characteristic curve for the derivation and validation cohorts were 0.868 and 0.894, respectively. In the validation cohort, the addition of a discriminative model score ≥2 to the ABC method showed a similar accuracy for predicting gastric cancer risk compared with the ABC method alone (93.8% vs. 92.4%).

CONCLUSION

The 4-point discriminative model may help identify patients with a normal serological test who are nonetheless at risk of developing gastric cancer.

Five Autoimmune Gastritis Patients with Positive Findings of Serum Anti-parietal Cell Antibodies

Autoimmune gastritis is a corpus-dominant type of gastritis with positive serum anti-parietal cell antibodies (APCA) and/or anti-intrinsic factor antibodies. Serum APCA and pepsinogen (PG) assays were performed in subjects with corpus-dominant gastritis detected by endoscopy. Serum APCA was positive in five patients. All these patients were postmenopausal women (four Koreans and one Caucasian from the Russian Federation) with a mean age of 59.0±3.2 years. They displayed low PG I levels ranging from 8.1 to 18.8 ng/mL (mean, 11.4±4.8 ng/mL) and low PG I/II ratios ranging from 0.7 to 2.4 (mean, 1.2±0.7). Three of the patients were being treated for autoimmune thyroiditis. Multiple gastric neuroendocrine tumors were observed in two Helicobacter pylori (H. pylori)-naive patients with high serum gastrin levels exceeding 700 pg/mL and serum chromogranin A levels exceeding 1,000 ng/mL. In the remaining three patients, intestinal metaplasia was observed in the biopsied specimens from the antrum, suggesting a history of H. pylori infection. Our findings indicate the value of positive serum APCA findings, low serum PG I levels, and low serum PG I/II ratios in confirming autoimmune gastritis in patients showing corpus-dominant atrophy, regardless of their H. pylori infection status.

Incidence of Infection among Subjects with Helicobacter pylori Seroconversion

Background/Aims

Helicobacter pylori (H. pylori) seroconversion may occur during screening for gastric cancer. Our study aimed to assess the number of seroconverted subjects with H. pylori and their results in follow-up tests.

Methods

Data were consecutively collected on subjects who were H. pylori-seronegative and presented for gastric cancer screening. Subjects who were followed up using the same serology test and pepsinogen (PG) assays on the day of endoscopy were included in the study.

Results

During the follow-up of 57.7 ± 21.4 months, 61 (15.0%) of 407 seronegative subjects showed seroconversion. H. pylori infection was detected in six (9.8%) of 61 seroconverted subjects. A diffuse red fundal appearance, with a significant increase in the Kyoto classification scores for gastritis, was observed in the infected subjects (p<0.001). Compared to the false-seropositive subjects, infected subjects showed higher serology titers (p<0.001) and PG II levels (p<0.001), and lower PG I/II ratios (p=0.002), in the follow-up tests.

Conclusions

Seroconversion occurred in 3.3% of seronegative subjects per year; however, only 9.8% had H. pylori infection. The majority (90.2%) of the seroconverted subjects showed false seropositivity without significant changes in the follow-up test results. The diffuse red fundal appearance could be an indicator of H. pylori infection.

Helicobacter pylori-negative Gastric Cancer

<i>Helicobacter pylori (H. pylori)</i>-negative gastric cancer is diagnosed when gastric malignancies are found in patients in <i>H. pylori</i>-naïve stomachs. There are four types of noncardiac <i>H. pylori</i>-negative gastric cancers. The signet ring cell-type poorly cohesive carcinoma is most common, followed by the chief cell-predominant type gastric adenocarcinoma of the fundic gland. Extremely well-differentiated adenocarcinoma of the corpus and well-differentiated pyloric gland cancers are rare outside Japan because of country-specific differences in diagnostic criteria. In endemic areas of <i>H. pylori</i> infection, strict criteria are required for diagnosing an <i>H. pylori</i>-naïve stomach. Both invasive and noninvasive <i>H. pylori</i> tests should show negative results in a subject without a history of <i>H. pylori</i> infection. Furthermore, the serum pepsinogen (PG) assay and endoscopic findings of the background gastric mucosa are required to discriminate subjects with past infections owing to spontaneous regression or unintended eradication of <i>H. pylori</i>. There should be no gastric corpus atrophy (PG I ≤70 ng/mL and PG I/II ≤3.0). Gastroscopy should reveal a regular arrangement of collecting venules without gastric xanthoma, metaplastic gastritis, or advanced atrophy over the angle. On biopsy, there should be no gastric atrophy, intestinal metaplasia, neutrophils, or <i>H. pylori</i> infiltration, and only a mild degree of mononuclear cell infiltration is permitted. The types and characteristics of noncardiac <i>H. pylori</i>-negative gastric cancers are summarized in this review, along with current diagnostic challenges found in Korea.

Optimized diagnosis of Helicobacter pylori and tailored eradication therapy for preventing gastric cancer: a proposal for SHAKE strategy

INTRODUCTION

To decrease gastric cancer-related mortality, the Korean National Cancer Screening Program provides biennial screening gastroscopy to all individuals aged >40 years. However, a test-and-treat strategy of Helicobacter pylori for preventing gastric cancer has not been established.

AREAS COVERED

In this review, we present up-to-date results of endoscopic findings of H. pylori gastritis, optimal sites for H. pylori detection, gastric cancer risk assessment using serum pepsinogen, tailored eradication based on the antimicrobial resistance against H. pylori, and post-eradication surveillance.

EXPERT OPINION

Here we propose approaches to H. pylori diagnosis and treatment for preventing gastric cancer, termed 'Screening for H. pylori in Korea and Eradication (SHAKE)' strategy. This strategy consists of the following: (1) optimized H. pylori diagnosis, (2) individualized management based on the H. pylori infection status, and (3) tailored eradication therapy. H. pylori gastritis can be diagnosed by endoscopic observation of the gastric mucosal pattern at the greater curvature of the corpus. Measurement of the serum pepsinogen I/II ratio is useful for assessing the risk of gastric cancer. As a first-line treatment, tailored eradication based on the results of molecular testing is effective in a country with a high rate of clarithromycin-resistant H. pylori.

Efficacy and safety of twice a day, bismuth-containing quadruple therapy using high-dose tetracycline and metronidazole for second-line Helicobacter pylori eradication

BACKGROUND/AIMS

Conventional second-line, bismuth-containing quadruple therapy is administered four times a day. We aimed to evaluate the efficacy and safety of twice a day administration compared to the four times a day therapy.

METHODS

Medical records of consecutive patients with positive ¹³ C-urea breath tests (UBTs) after first-line eradication were reviewed. From December 2018 to June 2019, 100 consecutive ¹³ C-UBT-positive patients received tetracycline 1 g, metronidazole 750 mg, bismuth subcitrate 300 mg, and pantoprazole 20 mg twice a day for one week. The same number of consecutive¹³ C-UBT-positive patients before December 2018 was included as controls. The control group received tetracycline 500 mg and bismuth subcitrate 300 mg four times a day, metronidazole 500 mg three times a day, and pantoprazole 20 mg twice a day for one week. Eradication was confirmed based on a ¹³ C-UBT performed in the 5th week after taking quadruple therapy.

RESULTS

Ninety-eight patients from the twice a day group and 99 patients from the four times a day group were analyzed. The eradication rate did not differ between the twice a day group (92/98, 93.9%) and the four times a day group (92/99, 92.9%). Adverse drug effects were found in 36 patients from the twice a day group and 50 patients from the four times a day group (P = .051). Abdominal pain, discomfort, and distention were more common with four times a day intake (13.1%) than with twice a day intake (4.1%; P = .024).

CONCLUSIONS

We determined for the first time that twice a day intake of bismuth-containing quadruple therapy using 2 g/d of tetracycline, 1.5 g/d of metronidazole, and 600 mg/d of bismuth subcitrate for one week is effective and safe as the conventional four times a day therapy. Twice a day intake decreased abdominal pain, discomfort, and distention.

Classifying risk level of gastric cancer: Evaluation of questionnaire-based prediction model

Objective

This study aimed at evaluating the efficacy of the questionnaire-based prediction model in an independent prospective cohort.

Methods

A cluster-randomized controlled trial was conducted in Changsha, Harbin, Luoshan, and Sheyang in eastern China in 2015−2017. A total of 182 villages/communities were regarded as clusters, and allocated to screening arm or control arm randomly. Face-to-face interview through a questionnaire interview, including of relevant risk factors of gastric cancer, was administered for each subject. Participants were further classified into high-risk or low-risk groups based on their exposure to risk factors. All participants were followed up until December 31, 2019. Cumulative incidence rates from gastric cancer between high-risk and low-risk groups were calculated and compared using the log-rank test. Cox proportional hazard regression models were applied to estimate hazard ratio (HR) and 95% confidence interval (95% CI).

Results

Totally, 89,914 residents were recruited with a mean follow-up of 3.47 years. And 42,015 (46.73%) individuals were classified into high-risk group and 47,899 (53.27%) subjects were categorized into low-risk group. Gastric cancer was diagnosed in 131 participants, of which 91 were in high-risk group. Compared with the low-risk participants, high-risk individuals were more likely to develop gastric cancer (adjusted HR=2.15, 95% CI, 1.23−3.76). The sensitivity of the questionnaire-based model was estimated at 61.82% (95% CI, 47.71−74.28) in a general population.

Conclusions

Our questionnaire-based model is effective at identifying high-risk individuals for gastric cancer.