bone scan shows stable -x rays show more damage

Bone scans taken over the past year showed hot spots in the same areas which my doctor took to be bone healing.  However a recent x-ray showed my areas of cancer damage compared with a 13 months ago. What's going on and how to interpret the results. Bone scan measures activity level and x ray measures bone structure.  Which do I  believe?

[Arti Sharma, M.D.]

Hi!
There are quite a few differences between an X-ray and a bone scan. A bone scan detects a problem earlier than a regular X-ray test. Areas that absorb little or no amount of tracer appear as dark or cold spots. This could show a lack of blood supply to the bone or certain types of cancer. While hot spots are areas of fast bone growth or repair which absorb more tracer. Hot spots are usually seen in conditions like arthritis, a tumor, a fracture, or an infection. Cancer spread to the bones can be seen in an Xray.Bone scans show entire skeleton and even asymptomatic disease can be picked up on bone scan. In cases of metastases when lesions are in less dense bones (purely osteolytic) bone sans may not pick up these lesions. In your case may be the results were not interpreted correctly .Any test result needs to be correlated clinically. It would have been really helpful if you had written more details about your condition. Discuss it with your doctor.
Best wishes!