Acneiform eruption secondary to radiotherapy
A 45-year-old man presented with T3N0M0 squamous cell carcinoma of the right tonsil. He underwent surgical therapy and megavoltage radiation therapy (70 Gy in 35 fractions). He developed several open and closed comedones along with some tender inflammatory papules over the irradiated area on both sides of his cheeks and neck, two months post radiotherapy. [Figure 1]. Lesional biopsy from neck demonstrated horn plugs blocking the hair follicles. A diagnosis of acneiform eruption secondary to radiotherapy was made. Topical tretinoin cream and oral isotretinoin (10 mg twice daily) were prescribed leading to rapid improvement within 4 weeks. Acneiform eruption with comedones is a late sequelae of radiation therapy which may develop between 2 weeks and 6 months following radiation therapy.1 Proper clinical and histopathological examination is needed in selected cases to rule out differentials like comedonal naevus, Favré–Racouchot syndrome and acne vulgaris.