TITLE: Prevalence and patterns of bone metastases detected with positron emission tomography using F-18 FDG.

REF: Clin Nucl Med. 2003 Apr;28(4):302-7. http://www.ncbi.nlm.nih.gov/entrez/...9&dopt=Abstract

STUDY TYPE: Retrospective Review

PATIENTS: 403 patients with proven malignant disease

FINDINGS: 38/403 (9%) had PET findings suggestive of bony metastatic disease. Of these 38 patients, only 29 were available for follow-up. Of the 29 patients with positive scans who were available for follow-up, 6 (21%) where false-positive. Bone scanning was positive in all patients who had a positive PET scan and also received a bone scan. However, the PET scan picked up more abnormal skeletal findings than the bone scan.

CONCLUSION: FDG PET is more sensitive than bone scanning on a lesion by lesion basis. However, both were equally sensitive on a patient by patient basis.

COMMENT: this study is lacking in that it doesn't track patients that received a bone scan but not a PET scan. We are unable to get a sensitivity and specificity for PET or bone scanning. This study is suggestive, but certainly not conclusive that PET is better than bone scanning for the detection of bony metastatic disease.

The false-positive rate is of concern. It appears that the false-positive rate of FDG PET was at least in part due to the researchers' interpretation criteria. They called as positive both focal AND diffuse bony uptake. Diffuse bony uptake in general is not suggestive of metastatic disease. FDG PET frequently shows diffuse bony uptake in patients receiving granulocyte colony stimulating factor.