Acute lymphoblastic leukemia (ALL), a malignant disorder of lymphoid progenitor cells, is the most common form of childhood cancer.(1) Fortunately, continued progress in the development of effective treatment regimes for ALL has led to a cure rate of >80%.(2) As cure rates improve, the sequelae attributed to the disease or its treatment are increasingly recognized, with skeletal health having emerged as an important short- and long-term concern for childhood ALL survivors.
Bone morbidity in childhood ALL has long been studied through retrospective review of radiographs and found to be associated with the leukemic process. Bone lesions have been apparent at the time of diagnosis and are purportedly more frequent in the appendicular than in the axial skeleton.(3) At appendicular sites, transverse metaphyseal radiolucencies, lytic and osteosclerotic lesions, and periosteal lifting have been observed in numerous reports.(4–7) Vertebral fractures have also been reported to occur in children with newly diagnosed ALL and have typically been considered a rare manifestation of the disease.(8–10) A large series of almost 1500 children who were evaluated for vertebral compression on routine chest radiographs at the time of ALL diagnosis found a vertebral fracture prevalence of <2%.(11) However, the specific methodology directing the vertebral fracture assessment, the pattern of vertebral fractures in the lumbar and thoracic spine, and the relationship between vertebral fractures and other skeletal parameters such as BMD were not reported.
Therefore, the purpose of this report was to carry out a prospective evaluation of the prevalence, location, severity, and morphology of thoracic and lumbar vertebral fractures in a large, multicenter cohort of children with newly diagnosed ALL. We further sought to determine the relationship between vertebral fractures and relevant clinical parameters such as the characteristics of the ALL, frequency of back pain, spine BMD, and cortical thickness.