Antimicrobial lock therapy for catheter-related infections in cancer patients: a systematic review and meta-analysis

Catheter-related infections remain a major healthcare-associated complication in patients with cancer requiring long-term central venous access. Antimicrobial lock therapy (ALT) has been proposed as a catheter-salvage strategy; however, its effectiveness and safety in adult oncology and hematology patients remain uncertain. Following PRISMA 2020, we searched PubMed/MEDLINE, Embase, Scopus, Web of Science, and the Cochrane Library from inception through September 2025. Studies evaluating therapeutic ALT for catheter-related infections in adult oncology and hematology populations were included. Outcomes were harmonized by construct and follow-up window. Absolute ALT-treated outcomes were pooled using random-intercept binomial-logit generalized linear mixed models when aligned, while comparative evidence was evaluated separately by study design and comparator. Risk of bias was assessed with design-specific tools, and GRADE was applied to comparative management-effectiveness evidence. Thirty-seven studies comprising 1,967 patients, infection episodes, or observations were included. Pooled early clinical response was 93.8% (95% CI, 90.3%–97.4%), early microbiological response 93.3% (79.6%–98.0%), sustained infection resolution at approximately 1 month 82.2% (73.5%–88.5%), short-term catheter salvage 84.2% (78.9%–88.3%), and catheter salvage at approximately 3 months 61.2% (56.5%–65.7%). Same-organism relapse was 7.8% (4.4%–13.5%) within approximately 1 month and 17.4% (13.2%–22.7%) during approximately 1–3 months; these estimates were derived from different studies and risk sets. Infection-attributable mortality was 1.45% (0.64%–3.24%). Comparative management-effectiveness evidence was limited and of very low certainty and did not establish a consistent advantage for ALT-based conservative strategies over alternative management, including catheter removal or reinsertion and systemic antimicrobial therapy without an active lock. Safety assessment and adverse-event reporting were heterogeneous. In the ETHALOCK randomized trial, catheter malfunction was more frequent with ethanol than with vancomycin lock therapy. Among ALT-treated patients, early infection control and short-term catheter salvage were frequently achieved, but these absolute outcomes do not establish comparative treatment benefit. ALT may be considered as an adjunctive salvage option in carefully selected patients when catheter preservation is clinically important and immediate removal is not otherwise indicated. Adequately powered, comparator-specific prospective studies using standardized definitions and prespecified follow-up are needed. PROSPERO CRD420251173835; registered 8 December 2025.