Ortho found proximal femur tumor on mri and is concerned for mets. having whole body fdg pet/ct. hx of hepatic adenomatosis, no known cancer except basal cell. vomit a lot from chronic migraine even w/zofran, can dehydration cause inaccurate results?

No dehydration is not likely to influence above mentioned imaging tests. Iv hydration might help with symptoms.

Your orthopedic surgeon is correct in the search for cancer, and dehydration has no influence on the findings. Am concerned regarding your increased vomiting and headaches, and would suggest imaging of the brain in addition. An oncologist should be involved. Hopefully, this turns out benign.