EGFR and acneiform dermatitis: In this subgroup, the incidence of acneiform dermatitis (86 cases, ROR = 6.14) and radiation-induced skin injury (68 cases, ROR = 5.99) was 3.2-fold higher than in younger patients, a pattern likely associated with diminished epidermal regenerative capacity and enhanced keratinocyte apoptosis triggered by EGFR inhibition.