Risk factors for severe radiation-induced dermatitis in nasopharyngeal carcinoma patients undergoing radiotherapy

Radiation-induced dermatitis (RID) is a common toxicity in patients with nasopharyngeal carcinoma (NPC) undergoing radiotherapy. This study aimed to evaluate the incidence, onset time, and factors associated with severe RID in patients with NPC.

This retrospective study included 287 patients with histologically confirmed NPC who received radiotherapy between August 2020 and August 2025. RID was graded according to the Radiation Therapy Oncology Group (RTOG) acute radiation morbidity criteria. Severe RID was defined as RTOG grade ≥3. Patients were classified into non-severe RID (RTOG grade 0-2) and severe RID groups. Baseline, clinicopathological, treatment-related, and laboratory variables were compared between groups. Logistic regression was used to identify factors associated with severe RID.

Patients were stratified into a non-severe group (RTOG grade 0-2, n = 201) and a severe group (RTOG grade ≥3, n = 86). The mean onset time was 24.8 ± 6.7 days for RTOG grade ≥1 RID and 37.6 ± 6.3 days for RTOG grade ≥3 RID. In multivariable analysis, older age (odds ratio [OR] = 1.03, 95% confidence interval [CI]: 1.01-1.06), smoking history (OR = 1.93, 95% CI: 1.11-3.55), higher total radiation dose (OR = 1.08, 95% CI: 1.01-1.15), elevated C-reactive protein (OR = 1.12, 95% CI: 1.06-1.20), higher neutrophil-to-lymphocyte ratio (OR = 1.53, 95% CI: 1.21-1.96), and larger irradiation area (OR = 1.16, 95% CI: 1.06-1.28) were positively associated with severe RID, whereas higher albumin was inversely associated with severe RID (OR = 0.89, 95% CI: 0.82-0.95).

Severe radiation-induced dermatitis was observed in 30.0% of patients with nasopharyngeal carcinoma receiving radiotherapy. Older age, smoking history, higher radiation dose, elevated inflammatory status, larger irradiation area, and lower albumin level were independently associated with severe radiation-induced dermatitis.