Characteristics of Primary and Metachronous Gastric Cancers Discovered after Helicobacter pylori Eradication: A Multicenter Propensity Score-Matched Study

Helicobacter pylori Eradication Does Not Adversely Affect the Clinical Course of Gastric Cancer: A Multicenter Study on Screening Endoscopic Examination in Japan

BACKGROUND

Since gastric cancers (GCs) detected after Helicobacter pylori (HP) eradication present with different morphological characteristics from conventional HP-positive GCs, delayed detection of early-stage GCs may be observed. This study aimed to investigate the clinical impact of HP eradication on diagnosing GC during screening endoscopy.

METHODS

Eleven health checkup institutions in Japan participated in the present study. All GC cases newly diagnosed by screening endoscopy between January 2016 and December 2020 were included. After propensity score matching, multivariable regression analysis was performed to estimate the effect of HP eradication on deep tumor invasion among HP-eradicated and HP-positive GC cases.

RESULTS

A total of 231 patients with GCs (134 HP-eradicated and 97 HP-positive cases) were enrolled. After propensity score matching, there were 81 cases in each group. The distribution of the depth of tumor invasion (pT1a, pT1b1, pT1b2, and pT2) between the HP-eradicated group and HP-positive group was similar (p = 0.82). In the propensity analysis, with HP-positive as the reference value, HP eradication was not significantly associated with T1b-T4-GCs and T1b2-T4-GCs, with odds ratios (95% confidence intervals) of 1.16 (0.48-2.81) and 1.16 (0.42-3.19), respectively.

CONCLUSIONS

HP eradication does not adversely affect the clinical course of GCs, supporting the recommendation of HP eradication in screening programs to reduce the total number of GC cases without delaying diagnosis.

Endoscopic characteristics and high-risk background mucosa factors of early gastric cancer after helicobacter pylori eradication: a single-center retrospective study

Purpose

Gastric cancer still develops after successful Helicobacter pylori(Hp)eradication. In this study, we aimed to explore the characteristics and risks of mucosal factors.

Methods

A total of 139 early gastric cancers (EGC) diagnosed in 133 patients after successful eradication from January 2016 to December 2021 were retrospectively included in the Hp-eradication EGC group and 170 EGCs diagnosed in 158 patients were included in the Hp-positive EGC group. We analyzed the clinical, pathological, and endoscopic characteristics between the two groups to identify the features of EGC after Hp eradication. Another 107 patients with no EGC after Hp eradication were enrolled in a Hp-eradication non-EGC group. The background mucosal factors between the Hp-eradication EGC group and the Hp-eradication non-EGC group were compared to analyze the high-risk background mucosal factors of EGC after eradication. In addition, we divided the EGC group after Hp eradication into IIc type and non-IIc type according to endoscopic gross classification to assess the high-risk background factors of IIc-type EGC after Hp eradication.

Results

The endoscopic features of EGC after Hp eradication included location in the lower part of the stomach (p=0.001), yellowish color (p= 0.031), and smaller size (p=0.001). The moderate/severe gastric atrophy (GA), intestinal metaplasia (IM) in the corpus, severe diffuse redness, and map-like redness were risk factors for EGC after eradication (p=0.001, p=0.001, p=0.001, and p= 0.005, respectively). The Kyoto classification total score in the EGC group was higher than the non-EGC group (4 vs.3 p<0.001). A multivariate analysis revealed that depressed erosion (OR=3.42, 95% CI 1.35-8.65, p= 0.009) was an independent risk factor for IIc-type EGC after Hp eradication.

Conclusion

EGC after eradication are smaller and yellowish lesions located in the lower part of the stomach. The risk background mucosal factors include moderate/severe GA, IM in the corpus, severe diffuse redness, and map-like redness. The Kyoto classification total score of 4 or more after successful eradication treatment might indicate EGC risk. In addition, the IIc-type EGC should be cautioned in the presence of depressed erosion after Hp eradication.

Clinical and endoscopic features of metachronous gastric cancer with possible lymph node metastasis after endoscopic submucosal dissection and Helicobacter pylori eradication

BACKGROUND

Several studies have reported the metachronous gastric cancers (MGCs) with possible lymph node metastasis (LNM) after endoscopic submucosal dissection (ESD) and Helicobacter pylori (H. pylori) eradication in which a curative ESD had not been achieved. There have been no published reports of evaluations of the features of patients with MGC with possible LNM after ESD and H. pylori eradication.

METHODS

We identified 264 patients with 369 MGCs after H. pylori eradication among the 4354 patients with 5059 early gastric cancers (EGCs) who underwent ESD between 1999 and 2017 and divided them into two groups: patients with MGCs with possible LNM (Group I) and patients with MGCs undergone curative ESD (Group II). We retrospectively compared the features of patients with MGCs and patients with EGCs at index ESD in the two groups.

RESULT

Group I consisted of 20 patients with 21 MGCs, and Group II consisted of 244 patients with 348 MGCs. Group I lesions were significantly more common in the posterior wall than in the lesser curvature (odds ratio [OR] = 3.97; 95% confidence intervals [CI] 1.20-13.10). Development of Group I was significantly more common in patients with a body mass index (BMI) < 19.0 kg/m2 than in patients with a BMI ≥ 19.0 kg/m2 at index ESD (OR = 4.44; 95% CI 1.30-15.20).

CONCLUSIONS

During surveillance endoscopy after gastric ESD and H. pylori eradication, the posterior wall should be carefully examined to detect MGCs early. Lower BMI may be associated with the development of MGCs with possible LNM.

Characteristics and background mucosa status of early gastric cancer after Helicobacter pylori eradication: A narrative review

Helicobacter pylori (H pylori) eradication treatment can reduce the risk of gastric cancer. However, early gastric cancer (EGC) can still be detected after eradication. Meanwhile, EGC after eradication is challenging to diagnose by an endoscopist in some cases due to the lack of apparent characteristics and the complex mucosal status. This review aims to summarize the endoscopic and histological characteristics and the mucosal risk factors for gastric cancer after H pylori eradication. The literature was searched for possible reported gastric cancer after eradication in "PubMed." These included related clinical studies and reviews, and unrelated or non-English articles were excluded. Endoscopically, EGC displays a small, reddish and depressed lesion, indistinct border, "gastritis-like" appearance and submucosal invasion. Histologically, it is divided into surface differentiation, nontumorous epithelium, and intestinal type. The risk factors include severe gastric atrophy, intestinal metaplasia in the corpus, and map-like redness. In conclusion, these studies on the characteristics and risk mucosal factors of patients with gastric cancer after H pylori eradication will drive the establishment of a novel endoscopic surveillance and diagnosis system for H pylori-eradicated patients.

Detection of Early Gastric Cancer after Helicobacter pylori Eradication

BACKGROUND

Based on evidence that Helicobacter pylori eradication reduces the development of gastric cancer and other diseases such as peptic ulcer, eradication therapy has prevailed. However, gastric cancer can develop even after successful eradication.

SUMMARY

In this review article, we searched for studies that identified the characteristics of primary and metachronous gastric cancers after H. pylori eradication, the risk factors for the development of these cancers after successful H. pylori eradication, and whether image-enhanced endoscopy is useful for diagnosing gastric cancer after eradication. A gastritis-like appearance is seen as a characteristic endoscopic finding, which corresponds to an epithelium with low-grade atypia - also known as nonneoplastic epithelium - covering the surface of the cancerous glands. This finding may make endoscopic detection of early gastric cancer difficult after H. pylori eradication. Similar risk factors, such as the male sex, endoscopic atrophy, histologic intestinal metaplasia, and late eradication, have been reported as predictors for the development of both primary and metachronous gastric cancers. Image-enhanced endoscopy, such as linked color imaging, may be useful for the detection and risk stratification of gastric cancer after eradication. Key Messages: Based on these findings, we believe that effective surveillance of high-risk patients leads to early detection of gastric cancer in the era of H. pylori eradication.

Relationship of prognostic factors in stomach cancer with Helicobacter pylori: A retrospective study

Background and study aims

The prognostic value of H. pylori, which infects more than half of the human population living in the world and plays a role in gastric cancer pathogenesis, is controversial. Our aim is to investigate the relationship between H. pylori and prognostic factors in gastric cancer.

Patients and methods

The data of 110 patients (38 females and 72 males) that underwent surgeries due to gastric cancer between 2014 and 2017 were retrospectively analyzed. The relationships between survival (disease-free and overall) and factors such as p53, HER2/neu, Ki-67, neutrophil and platelet lymphocyte ratio (NLR / PLR), histopathological and demographic characteristics were examined. In addition, the results of H. pylori positive and negative groups were compared.

Results

Sixty-one (55%) patients were H. pylori negative and 49 (45%) were positive. In multivariate analysis, TNM stage, lymph node capsule invasion and NLR were determined as independent prognostic factors in both disease-free and overall survival. Age>62 and PLR>14.3 were determined as independent predictive factors of poor prognosis in overall survival. In univariate analysis, tumor diameter of >4.3 cm, lymphovascular and perineural invasion, and diffuse p53 expression were determined as predictive factors of poor prognosis in disease-free and overall survival. The effectiveness of these markers in prognosis was not different between H. pylori negative and positive groups.

Conclusion

While age, tumor diameter, TNM stage, lymph node capsule invasion, perineural and lymphovascular invasion, diffuse p53, PLR, and NLR were determined as prognostic factors in gastric cancer, these factors were not affected by the presence of H. pylori.

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.

Chronic inflammation and long-lasting changes in the gastric mucosa after Helicobacter pylori infection involved in gastric cancer

OBJECTIVE

Helicobacter pylori (H. pylori) infects approximately half of the world's population, as one of the most common chronic infections. H. pylori infection has been widely recognized as a major risk factor for gastric cancer (GC).

METHODS

Eradication treatment is considered to abolish the inflammatory response and prevent progression to GC. However, only 1-3% of H. pylori-infected patients develop GC, whereas GC can occur even after eradicating H. pylori. In addition, the incidence of GC following H. pylori infection is significantly higher compared to the gross incidence induced by all causes, although eradicating H. pylori reduces the risk of developing GC.

RESULTS

Therefore, it is reasonable to hypothesize that H. pylori infection results in changes that persist even after its eradication. Several of these changes may not be reversible within a short time, including the status of inflammation, the dysfunction of immunity and apoptosis, mitochondrial changes, aging and gastric dysbacteriosis.

CONCLUSION

The present review article aimed to discuss these potential long-lasting changes induced by H. pylori infection that may follow the eradication of H. pylori and contribute to the development of GC.

Relationship of prognostic factors in stomach cancer with helicobacter pylori: a retrospective study

BACKGROUND AND STUDY AIMS

The prognostic value of H. pylori, which infects more than half of the human population living in the world and plays a role in gastric cancer pathogenesis, is controversial. Our aim is to investigate the relationship between H. pylori and prognostic factors in gastric cancer.

PATIENTS AND METHODS

The data of 110 patients (38 females and 72 males) that underwent surgeries due to gastric cancer between 2014 and 2017 were retrospectively analyzed. The relationships between survival (disease-free and overall) and factors such as p53, HER2/neu, Ki-67, neutrophil and platelet lymphocyte ratio (NLR / PLR), histopathological and demographic characteristics were examined. In addition, the results of H. pylori positive and negative groups were compared.

RESULTS

Sixty-one (55%) patients were H. pylori negative and 49 (45%) were positive. In multivariate analysis, TNM stage, lymph node capsule invasion and NLR were determined as independent prognostic factors in both disease-free and overall survival. Age>62 and PLR>14.3 were determined as independent predictive factors of poor prognosis in overall survival. In univariate analysis, tumor diameter of >4.3 cm, lymphovascular and perineural invasion, and diffuse p53 expression were determined as predictive factors of poor prognosis in disease-free and overall survival. The effectiveness of these markers in prognosis was not different between H. pylori negative and positive groups.

CONCLUSION

While age, tumor diameter, TNM stage, lymph node capsule invasion, perineural and lymphovascular invasion, diffuse p53, PLR, and NLR were determined as prognostic factors in gastric cancer, these factors were not affected by the presence of H. pylori.

Characteristics and Early Diagnosis of Gastric Cancer Discovered after Helicobacter pylori Eradication

The prevalence of gastric cancer after eradication (GCAE) is increasing dramatically in Japan. GCAE has characteristic features, and we must understand these features in endoscopic examinations. Differentiated cancer types were frequently found after eradication and included characteristic endoscopic features such as reddish depression (RD). However, benign RD can be difficult to distinguish from gastric cancer because of histological alterations in the surface structures (nonneoplastic epithelium or epithelium with low-grade atypia [ELA]) as well as multiple appearances of RD. Recently, we clarified similar alterations in genetic mutations between ELA and gastric cancer, suggesting that ELA is derived from gastric cancer. Clinically, submucosal invasive cancer was frequently found in patients after eradication therapy even if they received annual endoscopic surveillance. We can improve the diagnostic ability using image-enhanced endoscopy with magnified observation.

ABC Classification Is Less Useful for Older Koreans Born before 1960

Background/Aims

In the ABC classification system, group A consists of seronegative subjects without gastric corpus atrophy. This study aimed to determine the prevalence and characteristics of pseudo group A subjects.

Methods

Group A subjects were identified among consecutive Korean adults who underwent a serum anti-Helicobacter pylori immunoglobulin G (IgG) test and pepsinogen (PG) assay on the day of endoscopy. Past infection was defined as the presence of either eradication history or endoscopic findings suggesting past infection (i.e., gastric xanthoma, metaplastic gastritis, or advanced atrophy >closed-type 1).

Results

Among 2,620 group A subjects, 448 (17.1%) had eradication history, and 133 (5.1%) showed endoscopic findings suggesting past infection. Older age (odds ratio [OR], 1.148; 95% confidence interval [CI], 1.067 to 1.236) and earlier year of birth (OR, 1.086; 95% CI, 1.009 to 1.168) were independent risk factors for classification into pseudo group A, with cutoff points at 50.5 years and birth year of 1959.5, respectively. Positive H. pylori test findings were found in 22 subjects (3.1%) among the 715 subjects who underwent the urea breath test or Giemsa staining on the same day. Current infection was positively correlated with PG I and PG II levels (p<0.001) but not with age, anti-H. pylori IgG titer, or classification into pseudo group A.

Conclusions

Among the group A subjects, 22.2% had past infection. The risk was higher in subjects older than 50 years, especially those born before 1960. Furthermore, current infection was found in 3.1% of the subjects and was correlated with increased gastric secretory ability.

Gastric endoscopic submucosal dissection: a systematic review and meta-analysis on risk factors for poor short-term outcomes

OBJECTIVE

Endoscopic submucosal dissection (ESD) is now established as the first option to manage early gastric neoplasms, but its efficacy may vary according to diverse factors. We aimed to systematically identify risk factors for poor short-term outcomes of gastric ESD with the purpose to improve patients' selection and management.

METHODS

Three online databases (MEDLINE, ISI Web of Knowledge and Scopus) were searched (last search on June 2018) for poor outcomes of gastric ESD (deep submucosal invasion, piecemeal/incomplete resection, noncurative resection and local recurrence).

RESULTS

One hundred five studies were included referring to 52.126 ESDs. Undifferentiated histology and upper location (vs lower) were associated with submucosal invasion [odds ratio (OR) = 2.42 [95% confidence interval (CI), 1.62-3.61] and OR = 3.20 (1.04-9.86), respectively] and deep submucosal invasion [OR = 2.98 (2.02-4.39) and OR = 2.35 (1.45-3.81), respectively]. Lesion size greater than 30 mm and ulceration were associated with piecemeal resection [OR = 2.78 (1.17-6.60) and OR = 2.76 (1.23, 6.20), respectively]. Lesion size greater than 30 mm, ulceration, upper location and fibrosis were risk factors for incomplete resection [OR = 3.83 (2.68-5.49), OR = 4.06 (1.62-10.16), OR = 3.71 (2.49-5.54) and OR = 4.46 (1.66-11.96), respectively]. A noncurative resection was more often observed for lesions located in the upper third of the stomach [OR = 1.49 (1.24-1.79)], depressed morphology [OR = 1.49 (1.04-2.12)] and those outside standard criteria [OR = 3.56 (2.31-5.48)]. Older age was significantly linked with local recurrence rates [OR = 3.08 (1.13-5.02)].

CONCLUSION

Several risk factors influence poor efficacy short-term outcomes of gastric ESD that may be used to inform both patients and health providers about the expected efficacy.

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.

Prevention of gastric cancer by Helicobacter pylori eradication: A review from Japan

Japan introduced a Helicobacter pylori eradication therapy strategy in 2013, with the aim of decreasing the number of gastric cancer‐related death, the number of new cases of gastric cancer, and associated medical costs. Five years have passed since then, but no reduction in the annual number of gastric cancer has been observed. In addition, it was suggested that the number of deaths due to gastric cancer could be reduced to 30,000 a year by 2020, but the annual death toll in 2017 remained at more than 45,000. Based on the above evidence, it was examined whether it was possible to reach the target value based on the data from the last 5 years. The number of deaths per year in 2020 is predicted to be more than 40,000, which is clearly different from the target value. Logically, the effect of the strategy might appear by 2023. However, there is a possibility that the risk of gastric cancer may increase in some populations due to the influence of proton pump inhibitors and dysbiosis in the gastric microbiome. To solve these problems, combined therapy with PPIs and aspirin for patients after H pylori eradication should be considered.

Characteristics and predictors of gastric cancer after Helicobacter pylori eradication

Helicobacter pylori (H. pylori) eradication can reduce gastric cancer. However, gastric cancer still develops after eradication, and cases who received eradication therapy are increasing. In this study, we have reviewed the characteristics and predictors of primary gastric cancer developing after H. pylori eradication. In terms of the characteristics, endoscopic, histologic, and molecular characteristics are reported. Endoscopically, gastric cancer after eradication is often depressed-type and shows a gastritis-like appearance, which sometimes makes the diagnosis difficult. Histologically, most gastric cancer after eradication is intestinal type, and non-neoplastic epithelium, also called epithelium with low-grade atypia, is frequently seen over the tumor, which is presumably the cause of the endoscopic gastritis-like appearance. As for molecular characteristics, some markers, such as Ki67, MUC2, and Wnt5a expression, are lower in cancer from patients in whom H. pylori has been eradicated. In terms of predictors, several Japanese studies have reported that severe endoscopic atrophy at eradication is a risk factor for gastric cancer development. Histologic intestinal metaplasia, especially in the corpus, and long-term use of proton pump inhibitors, are also reported as risk factors for gastric cancer after H. pylori eradication. These studies on the characteristics and predictors of gastric cancer development will become the cornerstone for establishing a novel surveillance program based on the gastric cancer risk stratification specific to H. pylori-eradicated patients.