Pooled Oncological Outcomes in Marjolin's Ulcer: A Systematic Review and Meta-Analysis.

Marjolin's ulcer is a rare, aggressive cutaneous malignancy arising in chronic wounds, scars, and burns, for which prognostic and treatment data remain fragmented across small retrospective series. We conducted a systematic review and meta-analysis, registered with the International Prospective Register of Systematic Reviews (PROSPERO) and performed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA), searching PubMed, EMBASE, Scopus, the Cochrane Library, and ScienceDirect for case series and cohort studies (≥10 patients) reporting histologically confirmed malignancy arising in scars, ulcers, or chronic wounds. Pooled proportions were estimated using random-effects models (restricted maximum likelihood (REML)) with logit transformation, treatment arms were compared using log risk ratios, and risk of bias was assessed with the Joanna Briggs Institute (JBI) checklist. Fifty-one studies comprising 2,388 patients across 18 countries were included. Squamous cell carcinoma predominated (95.7%), arising chiefly in the lower limb (58.9%) after a long latency (median 29.5 years). The pooled local recurrence rate was 20% (95% confidence interval (CI) 16%-24%; I² = 66.3%), while the pooled rate of regional nodal metastasis at diagnosis was 19% (95% CI 15%-24%; I² = 78.5%); the pooled five-year overall survival was 61% (95% CI 49%-72%). Adding adjuvant radiotherapy to surgery showed no significant effect on local recurrence (log risk ratio 0.78, 95% CI -1.56-3.12), though confounded by indication. Evidence certainty was low to very low; wide local excision with clear margins, according to the oncological principles, remains the cornerstone of management.