Cutaneous granulocytic sarcoma arising at the site of radiotherapy for breast carcinoma

Carcinogenic effects of radiotherapy in breast cancer are well-known. Long-term follow-up of these patients shows a significantly increased risk of leukemia. Cutaneous granulocytic sarcoma is an uncommon leukemia cutis that usually occurs in association with acute myelocytic leukemia or myeloproliferative disorders. We report a case of cutaneous granulocytic sarcoma in a 44-year-old woman who had been treated six months earlier for breast adenocarcinoma. The treatment had associated lumpectomy, axillary lymph node dissection and radiotherapy. Skin lesions appeared firstly and predominantly on the irradiated area. Haematological investigations were normal and the diagnosis of isolated sarcoma was made. The uncommon features of this case were the short interval between radiotherapy and the occurrence of leukemia skin lesions and the fact that, to our knowledge, this is the first report of leukemia cutis localised on the irradiated area. The responsibility of radiation in the distribution of cutaneous lesions of granulocytic sarcoma is discussed.