[Henny]

Adriana,
In general the bone scan is better for blastic bone lesions (healing ones) and the PET is better for lytic lesions (new ones). The differences aren't great between the two so I would feel comfortable with either one-tho a bone scan is much less expensive if that's an issue.
If you really want to pull out the stops ask about the PET bone scan with sodium-fluoride instead of the FDG (sugar). The sodium fluoride scans seem to be the best but aren't available in many places-I think Stanford is doing a study on all 3 kinds of bone scans. I know they do quite a few sodium-flouride PET bone scans in Seattle too

Good luck!

Henny