A case with extraosseous Ewing's sarcoma: a late effect related to bone marrow transplantation for thalassemia or a component of a familial cancer syndrome?

Allogeneic bone marrow transplantation has proved to be a radical form of cure in patients with beta-thalassemia major who have a human leukocyte antigen identical donor. Although malignant neoplasms are serious late complications of bone marrow transplantation, very few reports describing the development of malignant tumors after allografting for thalassemia appeared in the literature. A case is presented here of extraosseous Ewing's sarcoma that developed 8 years after allogeneic bone marrow transplantation performed for beta-thalassemia major. The phenotypic features of the patient's family fulfill the criteria for Li-Fraumeni syndrome. The patient was treated with chemotherapy and radiotherapy and died with recurrent disease. To the authors' knowledge, this is the first case of extraosseous Ewing's sarcoma after bone marrow transplantation for thalassemia. The possible contribution of transplantation procedure and the genetic factors as well as the primary genetic hemoglobinopathy to the development of this malignant tumor are discussed.