Radiation‐Associated Lymphedema in Head and Neck Cancer: A Systematic Review and Meta‐Analysis

ABSTRACT Objective To estimate the pooled prevalence of lymphedema among adults with mucosal head and neck cancer treated with radiation therapy. Data Sources PubMed, Embase, Scopus, and Cochrane Library. Review Methods A comprehensive literature search of PubMed, Embase, Scopus, and Cochrane Library (2000–2025) identified cohort, case series, cross‐sectional, and clinical trial studies reporting lymphedema after radiotherapy for head and neck cancer. Logit‐transformed lymphedema prevalence was pooled using a DerSimonian‐Laird random‐effects model with Hartung‐Knapp‐Sidik‐Jonkman variance correction; statistical heterogeneity was evaluated using I 2 . This review was not prospectively registered. Results A total of 26 studies ( n = 3133 patients) met inclusion criteria. The pooled prevalence of lymphedema was 49% (95% CI, 36%–62%), with considerable heterogeneity (I 2 = 94%). Subgroup analyses yielded a pooled prevalence of 37% (12%–71%) for external and 45% (31%–60%) for internal lymphedema. Among studies reporting severity‐graded data, the pooled prevalence of clinically significant (grade ≥ 2) lymphedema was 32% (14%–59%). Lymphedema definitions and assessment methods varied across the included studies, most commonly employing clinical grading. Methodological quality was mixed, reflecting the predominantly retrospective, single‐arm nature of the available evidence. Overall certainty of evidence was very low. Funnel plot inspection and Egger's test suggested small‐study effects ( p = 0.06). Conclusion Lymphedema affects nearly half of patients following radiation for head and neck cancer. These findings may support routine surveillance, early identification, and timely referral for lymphedema management within survivorship care pathways. Future prospective studies should adopt standardized definitions and outcome measures to refine risk estimates and guide prevention strategies. Level of Evidence N/A.