ABSTRACT
Most lung cancer deposits in bone are lytic in type, but a few are mixed or sclerotic. These latter are mostly deposits from adenocarcinomas, bronchiolo-alveolar carcinomas or metastasising carcinoids. Some bones are difficult to demonstrate adequately by plain radiography e.g. the sternum and the sacrum. The fine colloid particles are readily taken up in the bone marrow, and defects within the normal pattern may be seen. Protons in cortical bone are immobile in a crystalline lattice. Skin deposits are not uncommon terminally with lung tumours, but may be the presenting feature. Choroidal deposits are more common than primary tumours, particularly melanomas. Positional information is superior from photons striking the periphery of the PM tubes, whilst energy measurement is best in their centres.
