Aneurysmal Bone Cyst: Its Roentgen Diagnosis

Abstract

During the past few decades a rather striking lesion of bone has been described in the literature under many seemingly unrelated designations: ossifying hematoma (4, 8, 28), subperiosteal giant-cell tumor (6, 13, 16, 24, 25, 27), atypical giant-cell tumor (7), aneurysmal giant-cell tumor (11), “hemorrhagic” bone cyst (2), expansile hemangioma (15), and aneurysmal bone cyst (1, 9, 10, 17, 18, 20, 21, 22). In recent years the term “aneurysmal” bone cyst has been most widely accepted. While the pathogenesis remains unsettled, there seems to be general agreement that the lesion is a distinct clinical and pathological entity, a fact established through the work of Jaffe and Lichtenstein (17, 18, 20, 21). The roentgenographic picture has been described as showing a diaphyseal and eccentric location and a characteristically expanding, “ballooned-out” shape having multiloculations (1, 17, 20, 27). While the occurrence of these cardinal roentgen features is evident, certainly there exists a need for fuller x-ray evaluation. As yet there has been no study devoted solely to roentgen diagnosis based upon a sufficiently large volume of material to establish the appearance of the lesion at various stages of its natural course, to demonstrate atypical cases, or to indicate the effect of treatment. Naturally, the ability to recognize these variations is a matter of importance to the diagnostic roentgenologist. The purpose of the present study is to evaluate the prevailing concept of roentgen diagnosis and, if it appears to be indicated, to enlarge on the roentgen criteria as concerns the unusual cases, natural history of the disease, and influence of surgery and irradiation. Material and Methods Forty-three histologically proved aneurysmal bone cysts with adequate x-ray coverage chosen from the files of Memorial Center, New York, constitute the material for the present analysis. This is the largest single series studied roentgenologically to date. More than 11 of the cases would be considered “atypical” roentgenologically if judged by existing roentgen criteria. The pathological diagnoses were made by various staff members of the pathology department of Memorial Center, and Dr. Arthur Allen reviewed all cases needing special consideration. Nineteen patients were males and 24 females. The age distribution was as follows: The median age was fifteen years, the mean age nineteen. The youngest patient was four, and the oldest sixty-one. Aneurysmal bone cyst is thought to be non-existent in infancy and rare among young children and older adults, being a disease of adolescence with its highest incidence between ten and nineteen years. One would suspect, however, that an aneurysmal bone cyst could remain clinically silent for some time and its discovery, therefore, be delayed or even incidental.