The CT scan of this canine thorax was carried out as part of a cancer staging exercise to identify if an appendicular (limb) bone tumour had metastasised to the patients lungs. CT imaging is more sensitive than conventional x-ray imaging in identifying the spread of tumours to the lungs. Thankfully this patient was free from metastatic disease and underwent limb-salvage surgery to remove the bone tumour whilst preserving the patient’s leg.