Incidence, Risk Factors, and Management of Radiotherapy-Related Skin Toxicity in Rectoanal Cancer Patients: a...

Radiotherapy is essential for rectoanal cancer, but pelvic anatomy and high radiation doses increase radiodermatitis risk, potentially compromising treatment efficacy. No specific meta-analysis exists for this group.

We systematically searched PubMed, Embase, Cochrane Library, and Web of Science up to September 2025. Pooled meta-analysis, network meta-analysis, and dose-effect meta-analysis were performed on 50 included studies (n = 4,892).

The overall radiodermatitis incidence was 58.7% (95% CI: 55.2%-62.1%), including severe (Grade ≥ 3, 12.3%) and moist desquamation (34.5%). Key independent risk factors (P < 0.05) were tumor distance ≤ 5 cm from anal verge (OR = 2.86), stoma absence (OR = 3.12), total dose > 50 Gy (OR = 2.59), concurrent chemotherapy (OR = 2.73), HIV infection (OR = 5.82), 3D-CRT vs. IMRT (OR = 8.76), and tumor skin invasion (OR = 36.0). Effective interventions included spray-type skin protectants (SUCRA = 92.3%), volumetric modulated arc therapy (VMAT; OR = 0.29 vs. 3D-CRT), recombinant human epidermal growth factor, and amifostine. A dose inflection point occurred at 50 Gy, with a 29% increased risk of severe dermatitis per additional 5 Gy above this threshold.

Skin toxicity is common in rectoanal cancer radiotherapy and linked to tumor, treatment, and patient factors. Optimized techniques (e.g., VMAT) combined with spray-type protectants enable precision management, improving outcomes.