Sources of Error in Radiological Interpretation in Tumors of Bone

Abstract

THE diagnosis of tumors of bone remains one of the most difficult problems confronting surgeons, radiologists, and pathologists, and this in spite of intensive study of the subject by large numbers of clinicians and research workers. The literature on every aspect of this problem is extensive, and great advances have been made in the diagnosis of these lesions. From the Bone Registry of the American College of Surgeons has come a workable classification of tumors of bone which has done much to bring order out of the chaos of confusing and clinically impractical terminology previously existing (Table I). Kolodny (1), in his masterly review of the material of the Bone Registry up to 1927, evolved a classification of primary malignant newgrowths of bone which is clear, concise, and very practical. His classification is as follows: (A) Osteogenic sarcoma (B) Ewing's sarcoma (C) Myeloma (D) Unclassified sarcoma The groups are arranged in the order of frequency of the various types of primary bone neoplasms. Osteogenic sarcoma is by far the most common of malignant bone tumors, accounting for about 80 per cent of all cases. Ewing's sarcoma has been variously quoted as comprising from 7 to 15 per cent of cases, while myeloma is responsible for about 3 per cent of hemangioendotheliomas and angiosarcomas of bone, which Kolodny carries in the unclassified group, and rare tumors, as is also the periosteal fibrosarcoma. There is no better illustration in the field of medicine of the need of close correlation of clinical and laboratory data than in the diagnosis of bone tumors. It is very hazardous to express an opinion on roentgenographs of bone lesions without having at least an accurate abstract of the clinical history, and any discrepancy between the two calls for a careful review of all the findings. With regard to the roentgenographs themselves, no effort should be spared to obtain as good visualization of the tumor as possible. Films should be made in at least two directions if the lesion is in a long bone, and stereoscopic views if the lesion involves the trunk or skull. In these cases patients should be closely questioned as to the presence of symptoms in other parts of the body, and roentgenographs made of any area of which they complain. In certain cases it will be necessary to make films of the entire skeleton to show multiple primary lesions or the presence of metastases. In all cases of suspected primary malignant newgrowth of bone, chest films should be made to discover possible metastases, because of the fact that the chest is the commonest site of secondary involvement in malignant bone tumors. The essential point in the radiological investigation of cases of suspected bone tumor is to determine whether the patient has or has not primary malignant disease of bone. This may well be approached by the following stages: First: Has the patient a tumor of bone? Second: Is the tumor benign or malignant? If malignant, is it primary or secondary?