Does the eradication of Helicobacter pylori delay the diagnosis of gastric cancer?

Eradication of Helicobacter pylori and Gastric Cancer: A Systematic Review and Meta-analysis of Cohort Studies

BACKGROUND

Helicobacter pylori (H. pylori) is associated with an increased risk of gastric adenocarcinoma and gastric mucosa associated lymphoid tissue (MALT) lymphoma and a decreased risk of esophageal adenocarcinoma. We aimed to assess how eradication therapy for H. pylori influences the risk of developing these cancers.

METHODS

This was a systematic review and meta-analysis. We searched PubMed, Web of Science, Embase, and the Cochrane Library and selected articles that examined the risk of gastric cancer, MALT lymphoma, or esophageal cancer following eradication therapy, compared with a noneradicated control group.

RESULTS

Among 3629 articles that were considered, nine met the inclusion criteria. Of these, eight cohort studies assessed gastric cancer while one randomized trial assessed esophageal cancer. Out of 12 899 successfully eradicated patients, 119 (0.9%) developed gastric cancer, compared with 208 (1.1%) out of 18 654 noneradicated patients. The pooled relative risk of gastric cancer in all eight studies was 0.46 (95% confidence interval [CI] = 0.32 to 0.66, I(2) = 32.3%) favoring eradication therapy. The four studies adjusting for time of follow-up and confounders showed a relative risk of 0.46 (95% CI = 0.29 to 0.72, I(2) = 44.4%).

CONCLUSIONS

This systematic review and meta-analysis indicates that eradication therapy for H. pylori prevents gastric cancer. There was insufficient literature for meta-analysis of MALT lymphoma or esophageal cancer.

Treatment of gastric outlet obstruction that results from unresectable gastric cancer: Current evidence

Malignant gastric outlet obstruction (GOO) is a common condition that results from locally advanced malignancies in the upper gastrointestinal tract, such as pancreatic, gastric, and other carcinomas. Two types of procedures for malignant GOO, namely, gastrojejunostomy (GJ) with laparotomy or a laparoscopic approach and endoscopic stenting (ES), are currently available. Although numerous previous reports have clarified the benefits and drawbacks of each procedure, whether GJ or ES should be used in patients with GOO that results from gastric cancer who may have a longer life expectancy than patients with other malignancies has not been determined. In this review, which focuses on gastric cancer-induced GOO, we analyzed the two systematic reviews and a meta-analysis that compared GJ and ES and outlined the current status of GOO treatment. We also provide an updated review that includes laparoscopic GJ. Various data from 13 studies in one review and 6 studies in another review were analyzed. Although the main results of the present review indicated that both GJ and ES were efficacious treatments in patients with GOO that resulted from gastric cancer, current evidence suggests that GJ may be the preferable procedure given its good performance status and improved prognosis in gastric cancer patients.

Gastric outlet obstruction in gastric cancer: a comparison of three palliative methods

BACKGROUND

Gastric outlet obstruction (GOO) commonly occurs in advanced gastric cancer. Our aim was to evaluate the results of endoscopic stenting (ES), palliative resection (PR), and gastrojejunostomy (GJ) as palliation of GOO.

METHODS

A total of 97 patients (50 ES, 26 PR, 21 GJ) were included in this retrospective study. All the patients had primary gastric cancer and symptoms of GOO.

RESULTS

Compared to surgery, ES resulted in a faster improvement on oral intake and symptom relief (P < 0.001) and a shorter hospitalization (P < 0.001). Complication rates, hospital re-admissions, occurrence of biliary obstruction, and the number of patients receiving chemotherapy were similar. The median symptom-free and overall survival were longest in the PR group (P < 0.001). In multivariate survival analysis, independent prognostic factors were age, BMI, pre-procedure GOOSS, palliative resection as treatment modality, and chemotherapy.

CONCLUSIONS

In gastric cancer and GOO, the clinical condition of the patient before treatment affects survival and should be taken into account in determining the treatment. PR seems to provide a survival benefit and should be considered as treatment option for patients suitable for surgery. For patients unfit for surgery, ES provides rapid and efficient palliation. Chemotherapy also seems to improve survival in gastric cancer and GOO.

Does non-curative gastrectomy improve survival in patients with metastatic gastric cancer?

BACKGROUND

The role of non-curative or palliative gastrectomy remains controversial. Our aim was to compare retrospective patients who have undergone non-curative gastrectomy to the patients with surgical exploration only.

METHODS

Between years 2000 and 2009, 488 patients with gastric adenocarcinoma were treated at the Department of Surgery, Helsinki University Central Hospital. Fifty-five patients had metastatic disease but their symptoms were not severe enough to require palliative surgery. Thirty-two of them underwent operative exploration (Group A), and 23 non-curative gastrectomy (Group B). All operations were initiated with curative intent.

RESULTS

The difference in median survival between Groups A and B was insignificant (5.7 months in Group A and 10.8 months in Group B, P = 0.152). However, 33 patients with postoperative chemotherapy had significantly better median survival than the others (14.2 months vs. 1.9 months, P < 0.001). No significant differences were observed between Groups A and B in the rate of late postoperative gastrointestinal obstruction or bleeding.

CONCLUSIONS

Non-curative gastrectomy does not improve survival in patients with metastatic gastric cancer, nor reduces the rate of late occlusions. There is no need for prophylactic palliative gastrectomy in patients with gastric cancer who do not have bleeding or obstruction preoperatively. Among those patients, postoperative chemotherapy seems to improve survival.

Clinical prevention of gastric cancer by Helicobacter pylori eradication therapy: a systematic review

Helicobacter pylori (H. pylori) infection plays an important role in gastric carcinogenesis. We conducted a systematic review concerning gastric cancer development after H. pylori eradication therapy. In total 15 papers matched our criteria, the results were reviewed. The H. pylori eradication therapy statistically diminished the prevalence of clinical gastric cancer by approximately one-third. The studies from Japan supported this conclusion; however, studies from overseas reported conflicting results. The differences in these conclusions lie in the diagnostic ability of endoscopic examination, since the clinical stage was quite different between these studies. Gastric cancer that developed after eradication revealed a mainly intestinal type histology and depressed-type appearance. The following are possible reasons for reduced gastric cancer: (1) eradication therapy inhibits the new occurrence of gastric cancer, (2) eradication regresses or inhibits the growth of gastric cancer, and (3) eradication interferes with the discovery of gastric cancer. Considering the biological nature of cancer cell proliferation, a sufficiently long-term follow-up may clarify the effect of eradication therapy on inhibition of the development (not discovery) of gastric cancer and reduction of gastric cancer-related mortality.