The Bone Lesions of Childhood Leukemia

Abstract

The bone changes of childhood leukemia, present in about two-thirds of cases, are often of value for differentiation when the clinical diagnosis is obscure. Although the bone lesions are not specific for this disease, except perhaps in the late stages, they are of significance in that similar lesions are not usually associated with the diseases which leukemia most often resembles clinically. The transverse line of radiolucency beneath the metaphyses of the long bones, the earliest and most common manifestation of bone involvement in leukemia, is rare in other diseases of children over the age of two years. The extensive destructive lesions in the long bones occurring late in the disease present a characteristic pattern not seen in other conditions, except perhaps metastatic neuroblastoma. Earlier stages of destruction, periosteal reaction, and osteosclerosis are other changes which may be present in a recognizable pattern, or may give a clue as to the diagnosis when interpreted in the light of the clinical findings. For many years, since about 1932, it has been the practice in the Harriet Lane Home of The Johns Hopkins Hospital to include roentgenographic examination of the long bones in the study of cases of suspected leukemia when the diagnosis was not certain clinically. Often such studies have served simply to confirm a suspected diagnosis. Occasionally, however, they have been sufficiently important to be the prime factor in establishing the nature of the disease. The present study was undertaken to investigate the diagnostic value of lesions of the long bones in leukemia. Long-bone examinations in 140 proved cases available in the Pediatric Division of the Department of Radiology of this institution were reviewed. The general incidence in other diseases of one of the important leukemia lesions, namely the transverse line of radiolucency beneath the metaphysis, was also investigated. Finally, the bone lesions of leukemia, generally, were compared with long-bone lesions in those diseases which leukemia most often resembles clinically. Review of the Literature Kalayjian, Herbut, and Erf (10), in 1946, collected from the literature 144 cases of childhood leukemia with long-bone lesions, mostly isolated case reports. To these they added 2 cases of their own. They divided the lesions into four types: (a) a transverse line of radiolucency beneath the metaphyses of the long bones; (b) osteolytic destructive lesions; (c) periosteal reaction; (d) osteosclerosis. Others have given similar descriptions (17). Baty and Vogt (1) first described the radiolucent metaphyseal line in 1935. They found it to be the most common bone change, present in 70 per cent of their series of 43 cases. Silverman (14), in 1948, reported a series of 103 cases, the largest previously presented, with a detailed review of the literature.