Radiological behaviour patterns of bone tumours

The radiograph is usually the first step in diagnosis of tumorous bone lesions. Although definitive diagnosis depends on biopsy in many instances the radiograph allows the most essential decision on malignancy or benignity. This radiological grading of neoplasitc bone disease is based on various criteria, in particular the pattern of bone destruction and behaviour of the cortex. 3 main types of bone destruction predicting tumour behaviour can be differentiated: 1. the geographic well-defined destruction which is characteristic of static or slowly growing lesions; 2. moth-eaten pattern with scattered and confluent holes reflecting a highly aggresive lesion; 3. most aggresive permeative pattern characterized by multiple tiny holes. The cortex also reflects the response of normal bone against destruction. Depending on the activity of the process, the cortex will either remain intact, or will be expanded, or is even penetrated. The characteristic features of the different destruction patterns are illustrated by radiographs and corresponding pathologico-anatomical slices. (orig.)