Background
Systematic review and meta-analysis. 63 studies, 5,765 patients with keloids treated with post-excision RT. Compared recurrence rates across: (1) RT fractionation schedules (single fraction vs multi-fraction); (2) anatomic site; (3) RT timing post-excision; (4) RT source (electron, superficial X-ray, brachytherapy). Mankowski P et al, Ann Plast Surg 2017 — the most comprehensive meta-analysis of keloid RT to date.
Interventions and follow up
Arm A: Various postoperative RT regimens compiled from 63 studie
Primary endpoint: Keloid recurrence rate
mFollow up: 1–5 years (variable across studies)
Primary endpoint: Keloid recurrence rate
mFollow up: 1–5 years (variable across studies)
Results
Comparison: Single fraction vs multi-fraction; electron vs superficial X-ray vs brachytherapy; timing (immediate vs delayed)
Overall pooled recurrence: 22.7%
Single fraction (10–20 Gy): Recurrence 22% vs multi-fraction 23% — equivalent
Brachytherapy recurrence: 20% — similar to EBRT
RT within 24 hr post-excision: Recurrence 15% vs >24 hr 32%, P<.001
Anatomic site (ear): Recurrence 8%; sternal: 35%
Overall pooled recurrence: 22.7%
Single fraction (10–20 Gy): Recurrence 22% vs multi-fraction 23% — equivalent
Brachytherapy recurrence: 20% — similar to EBRT
RT within 24 hr post-excision: Recurrence 15% vs >24 hr 32%, P<.001
Anatomic site (ear): Recurrence 8%; sternal: 35%
Adverse events
Main adverse events: Hyperpigmentation (30%), skin atrophy (8%), telangiectasia (7%). All across heterogeneous studies. Rare: secondary malignancy not reported in any included study at this follow-up.
Conclusions
Post-excision RT reduces keloid recurrence to ~23% overall. Single-fraction and multi-fraction regimens have similar efficacy. Immediate RT (within 24 hours) is significantly more effective than delayed RT. Site matters: ear keloids respond best; sternal keloids have highest recurrence regardless of technique.
Key Limitations
Key Limitations: Majority of included studies are retrospective with high heterogeneity. Publication bias toward positive outcomes. Standardized keloid staging, excision techniques, and patient-reported outcomes are lacking. Secondary malignancy risk with RT near critical structures in young patients requires longer follow-up than available in this analysis.
Clinical Context
The Mankowski meta-analysis is the most cited evidence synthesis for keloid RT. It confirms: (1) RT within 24 hours of excision is essential; (2) single-fraction and multi-fraction are equivalent; (3) sternal keloids need aggressive management. Most centers use 15–18 Gy/3 fractions for practical and fractionation-tolerance reasons over single-fraction.
References