What is the significance of a single rib lesion in a patient undergoing evaluation for metastatic disease from a known primary cancer?
The traditional view is that a single rib lesion has approximately an 8% to 10% chance of being a metastasis; this can be modified by the characteristics of the finding. Typically, linear areas of increased activity that appear to extend along the rib are more suggestive of metastatic disease, whereas small macular lesions are more likely the result of trauma. In addition, the patient’s history might reveal a recent fall, which would also more likely suggest that the finding is the result of trauma.
When multiple, rib fractures are often seen to involve multiple adjacent ribs, whereas rib metastases tend to be more randomly distributed in location.