Systematic Reviews
Copyright ©The Author(s) 2023. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Apr 14, 2023; 29(14): 2202-2221
Published online Apr 14, 2023. doi: 10.3748/wjg.v29.i14.2202
Effectiveness of Helicobacter pylori eradication in the treatment of early-stage gastric mucosa-associated lymphoid tissue lymphoma: An up-to-date meta-analysis
Fabian Fellipe Bueno Lemos, Caroline Tianeze de Castro, Mariana Santos Calmon, Marcel Silva Luz, Samuel Luca Rocha Pinheiro, Clara Faria Souza Mendes dos Santos, Gabriel Lima Correa Santos, Hanna Santos Marques, Henrique Affonso Delgado, Kádima Nayara Teixeira, Cláudio Lima Souza, Márcio Vasconcelos Oliveira, Fabrício Freire de Melo
Fabian Fellipe Bueno Lemos, Mariana Santos Calmon, Marcel Silva Luz, Samuel Luca Rocha Pinheiro, Clara Faria Souza Mendes dos Santos, Gabriel Lima Correa Santos, Henrique Affonso Delgado, Cláudio Lima Souza, Márcio Vasconcelos Oliveira, Fabrício Freire de Melo, Instituto Multidisciplinar em Saúde, Universidade Federal da Bahia, Vitória da Conquista 45029094, Bahia, Brazil
Caroline Tianeze de Castro, Instituto de Saúde Coletiva, Universidade Federal da Bahia, Salvador 40110040, Bahia, Brazil
Hanna Santos Marques, Campus Vitória da Conquista, Universidade Estadual do Sudoeste da Bahia, Vitória da Conquista 45029094, Bahia, Brazil
Kádima Nayara Teixeira, Campus Toledo, Universidade Federal do Paraná, Toledo 85919899, Paraná, Brazil
Author contributions: Lemos FFB, Castro CT, Teixeira KN, Souza CL, Oliveira MV, and Freire de Melo F contributed to the conceptualization of the manuscript; Lemos FFB, Castro CT, Teixeira KN, Souza CL, Oliveira MV, and Freire de Melo F designed the study methodology; Lemos FFB, Castro CT, Calmon MS, Silva Luz M, Pinheiro SLR, Faria Souza Mendes dos Santos C, Santos GLC, Marques HS and Delgado HA were responsible for manuscript visualization; Lemos FFB, Calmon MS, Silva Luz M, Pinheiro SLR, Faria Souza Mendes dos Santos C, Santos GLC, Marques HS, Delgado HA, Teixeira KN, Souza CL, Oliveira MV, and Freire de Melo F contributed to the investigation; Lemos FFB, Calmon MS, Silva Luz M, Pinheiro SLR, Faria Souza Mendes dos Santos C, Santos GLC, Marques HS, Delgado HA performed formal analysis; Lemos FFB wrote the original draft; Castro CT and Silva Luz M were responsible for manuscript editing; Castro CT, Silva Luz M, Teixeira KN, Souza CL, and Oliveira MV were responsible for manuscript writing and review; and Freire de Melo F supervised the writing of the original draft.
Supported by the Scientific Initiation Scholarship Programme (PIBIC) of the Bahia State Research Support Foundation, FAPESB, Brazil; the Doctorate Scholarship Program of the Coordination of Improvement of Higher Education Personnel, CAPES, Brazil; the Scientific Initiation Scholarship Programme (PIBIC) of the National Council for Scientific and Technological Development, CNPq, Brazil; and the CNPq Research Productivity Fellowship (PQ).
Conflict-of-interest statement: All the authors report no relevant conflicts of interest for this article.
PRISMA 2009 Checklist statement: The authors have read the PRISMA 2009 Checklist, and the manuscript was prepared and revised according to the PRISMA 2009 Checklist.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: https://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Fabrício Freire de Melo, PhD, Professor, Instituto Multidisciplinar em Saúde, Universidade Federal da Bahia, Estrada do Bem Querer, 3293-3391 - Candeias, Vitória da Conquista 45029094, Bahia, Brazil. freiremeloufba@gmail.com
Received: November 19, 2022
Peer-review started: November 19, 2022
First decision: November 30, 2022
Revised: December 10, 2022
Accepted: March 14, 2023
Article in press: March 14, 2023
Published online: April 14, 2023
ARTICLE HIGHLIGHTS
Research background

Gastric mucosa-associated lymphoid tissue (MALT) lymphoma (GML) is usually a low-grade, B-cell neoplasia strongly associated with Helicobacter pylori (H. pylori)-induced chronic gastritis. As such, clinical practice guidelines currently recommend H. pylori eradication as the preferred initial treatment for early-stage GML.

Research motivation

Studies that aim to evaluate the effects of H. pylori eradication on early-stage GML are generally small and heterogenous single-arm uncontrolled observational studies. Hence, we recognized the need for an updated powerful statistical synthesis of the available evidence regarding the practical effect of H. pylori eradication as sole initial therapy for early-stage GML.

Research objectives

We aimed to perform a systematic review with an up-to-date proportional meta-analysis (P-MA) to assess the complete remission (CR) rate of H. pylori-positive early-stage GML after bacterial eradication therapy.

Research methods

We performed independent computer-assisted searches of PubMed/MEDLINE, Embase and Cochrane Central databases culling reports published before September 2022. Prospective and retrospective observational studies evaluating the CR rate of early-stage GML after bacterial eradication therapy in H. pylori-positive patients were eligible for inclusion. The risk of bias was assessed using the JBI Critical Appraisal Tools. We followed the random-effects model to calculate the pooled estimate of the complete histopathological remission rate and respective confidence intervals (95%CI). We used Cochran’s Q test and I2 statistic to assess the heterogeneity and inconsistency, and we set the threshold for heterogeneity as P < 0.01 and I² > 50%, respectively. Subgroup and meta-regression analyses were conducted to explore potential sources of heterogeneity.

Research results

P-MA highlighted that the overall CR of H. pylori-positive early-stage GML after bacterial eradication was 75.18% (95%CI: 70.45%-79.91%). On the other hand, the substantial heterogeneity observed across studies (I2 = 92%; P < 0.01) limits, but does not preclude, the interpretation of the pooled overall CR rate. Subgroup analysis revealed that retrospective and prospective studies presented similar overall CR rate estimates after eradication therapy: 75.51% (95%CI: 64.96%-86.07%; I2 = 96%; P < 0.01) and 75.08% (95%CI: 69.80%-80.36%; I2 = 89%; P < 0.01), respectively. Nevertheless, meta-regression analysis indicated that the proportion of patients with t(11;18)(q21;q21)-positive GML and the studies’ risk of bias were sources of heterogeneity. More precisely, studies with greater than 30% of patients with t(11;18)(q21;q21)-positive GML and high risk of bias decrease in 0.40 (95%CI: -0.59 to -0.22; P < 0.0001) and 0.43 (95%CI: -0.77 to -0.09; P = 0.0139) the pooled estimate of the CR rate, respectively.

Research conclusions

Comprehensive evidence synthesis suggests the effectiveness of H. pylori eradication as the sole initial therapy for early-stage GML. Although the substantial heterogeneity observed across studies limits the interpretation of the pooled overall CR rate, the present study is a relevant alternative for informing clinical practice.

Research perspectives

Inadequate reporting was an important reason for the exclusion of studies during screening and a complicating factor for data extraction. As reliable and robust studies are scarce in our field, we emphasize that proper reporting of the available evidence is vital to inform clinical practice. Further robust comparative observational studies are needed to identify predictive factors for GML remission following H. pylori eradication and to provide more reliable evidence in our field.