From toasted skin to tumors: a retrospective nationwide case-control analysis investigating the link between erythema ab igne and various skin cancers

This study investigated erythema ab igne (EAI) and comorbid skin cancers. Each EAI case, searched by ICD-10-CM code L59.0 in the All of Us database, was compared to four controls, matched by sex at birth, age, and self-identified race/ethnicity. Demographics and skin cancer comorbidities were assessed with odds ratios (ORs) and 95% confidence intervals (CIs) using Wald's method. EAI was most prevalent between 60 and 70 years of age. A female-to-male ratio of 1:1 was observed between ages 40 and 50. EAI patients had a statistically significant increased risk of basal cell carcinoma (OR, 10.67; 95% CI, 2.76-41.30; <i>P</i> < 0.001), squamous cell carcinoma (OR, 27.84; 95% CI, 1.42-545.59; <i>P</i> = 0.03), and melanoma (OR, 8.00; 95% CI, 1.43-44.60; <i>P</i> = 0.02). Additional tumors were analyzed, but insufficient case/control data was obtained from the database. In conclusion, EAI is positively correlated with skin cancers. Awareness and prevention of EAI is warranted.