Generalized lichen ruber planus - Induced by radiotherapy of the breast?

Background: Lichen ruber planus is an inflammatory, pruritic disease of the skin and mucous membranes, which can be either generalized or localized. The etiology is unknown. Patients and Methods: A 56-year-old female was treated with standard local radiotherapy after breast-conserving surgery due to high-grade ductal carcinoma in situ ( DCIS) of the breast. Results: During radiotherapy, the patient began to complain about increasing disseminated itching papules of the breast. The efflorescences appeared as flat-topped, solid, purplish papules spreading to the limbs and trunk. A thorough clinical examination revealed additionally suspicious cob-web like and white-coated mucosal lesions of the oral cavity consistent with the clinical diagnosis of a generalized lichen ruber planus with an oral manifestation. Conclusion: To our knowledge, this is the first report of a generalized manifestation of lichen ruber planus presumably induced by radiation therapy.