Pre-conditioning total body irradiation for bone marrow transplantation induces systemic bone changes

Introduction For the treatment of childhood leukemia and other oncologic disorders, total body irradiation (TBI) associated with high doses of chemotherapy had been included in some of the conditioning regimens given before an allogeneic bone marrow transplantation (BMT) 1). The increasing use of BMT in the treatment of malignant diseases in childhood has revealed several long-term sequelae such as multiple endocrine abnormalities, abnormal growth, delayed puberty, gonadal dysfunction, and hypothyroidism 2) . Among long-term survivors of childhood cancer who received TBI, the incidence of osteochondroma is well known. Recently, we reviewed plain radiographs of 7-year-old boy who had knee and lower extremities pain ( Fig. 1, case 5) . He was a long-term survivor of stage IV neuroblastoma with a history of TBI and BMT during the previous 4 years. A variety of bony abnormalities were demonstrated on a skeletal survey such as osteochondroma, epiphyseal and metaphyseal dysplasia, and numerous vertical metaphyseal striations. This constellation of unusual bony changes reminded us of skeletal dysplasia. After some diagnostic confusion, we finally diagnosed TBI-induced systemic bone changes . These observations prompted us to review the skeletal radiographs of other longterm survivors of TBI at our institution. The aim of this study is to evaluate systemic bone changes related to TBI used in pre-transplant conditioning for BMT. Reiko Okamoto, Osamu Miyazaki, Gen Nishimura*, Hidekazu Masaki, Kumiko Nozawa* *, Hiroshi Kitoh * * * Department of Radiology, National Center for Child Health and Development. *Department of Radiology, Tokyo Metropolitan Kiyose Children’s Hospital. * * Department of Radiology, Saitama Children’s Medical Center. * * *Department of Orthopedic Surgery, Nagoya University Hospital.