Acupuncture Therapies for Chemotherapy-Induced Nausea and Vomiting in Patients With Breast Cancer: Protocol for a Systematic Review and Network Meta-Analysis

Background: As a prevalent side effect, chemotherapy-induced nausea and vomiting (CINV) imposes a burden on the daily lives of patients with breast cancer. Multiple clinical trials have suggested the validity of acupuncture in alleviating CINV; however, the optimal acupuncture modality remains unclear. Objective: This protocol describes a systematic review and network meta-analysis to investigate the efficacy and safety of distinct acupuncture interventions for treating CINV in patients with breast cancer. Methods: Eight databases (PubMed, Embase, Web of Science, the Cochrane Library, China National Knowledge Infrastructure, VIP Database, Wanfang Database, and the Chinese Biomedical Literature Database) will be searched for eligible studies from their respective inception to July 31, 2025. The language of published studies is limited to English and Chinese. Primary outcomes are CINV intensity and clinical effectiveness rates. Secondary outcomes include recurrence rates, safety outcomes, and quality of life. Risk of bias will be assessed using the Cochrane risk of bias tool. Pairwise meta-analysis will be conducted in Stata using random-effects models with Hartung-Knapp-Sidik-Jonkman CIs. Network meta-analysis will be conducted using Bayesian Markov chain Monte Carlo methods in R software. Convergence will be assessed using Gelman-Rubin statistics and trace plots. Heterogeneity will be summarized using τ2 and τ, along with prediction intervals, when applicable. Consistency between direct and indirect evidence will be evaluated using the node-splitting method and design-by-treatment interaction test. Small-study effects will be assessed via comparison-adjusted funnel plots and the Egger test in Stata. Where feasible, subgroup analyses and meta-regression analyses will be performed. The certainty of evidence will be evaluated using the Grading of Recommendations Assessment, Development, and Evaluation framework. Results: A preliminary scoping search was completed in August 2025, and this protocol was finalized in October 2025. The comprehensive literature search and study selection are expected to be completed by June 2026, followed by data extraction by August 2026. Data synthesis and final manuscript preparation are scheduled to be completed by December 2026. Conclusions: This analysis will expand the range of evidence-based acupuncture options available to clinicians for treating CINV in patients with breast cancer.