Sclerotic medullary spread in diaphyseal osteosarcoma.

Dense medullary sclerosis is reported in the shafts of long bones accompanying diaphyseal osteosarcoma. Histological evidence suggests that this indicates more extensive medullary spread of tumour than is readily apparent on standard radiographic examination. It would appear that these sclerotic lesions show active radio-isotopes retention following skeletal scintigraphy. The clinical and radiological features and prognostic implications of these findings are discussed.