[CT of tumorous lesions of the osseous pelvis]

Three hundred and fourteen CT examinations in 186 patients with primary and secondary bone tumours, or tumour-like lesions, in the pelvis have been analysed with regard to the type of lesion. Signs of malignancy are extra-osseous extension of the tumour, extension to other bones across joints, infiltration and destruction of the bone, absence of a margin and amorphous calcification within the lesion. Signs of a benign lesion are intra-osseous tumour growth without soft tissue involvement, even in the presence of localised destruction of the cortex, maintenance of the normal bone limits, marginal sclerosis and structured calcification. The histological type can be suggested in tumour-like lesions and, with some limitation, for some bone tumours.