The aim of this study is to detect bone metastases by PET/CT examination in cancer patients.

Bone is a fertile soil for dissemination of metastatic tumor cells which can cause either osteolytic ( destructive) or osteoblastic (sclerotic) or mixed lesions in advanced cancer. Bone metastases are most common throughout the axial skeleton, this leads to major complications referred to as skeletal-related events (SREs), the most frequently are the need for radiotherapy and pathological fractures, associated with increase life morbidity and decrease overall survival.

Seeking accurate image modalities provides definite staging, determining the optimal strategy of treatment and precise evaluation to decrease the burden of complication.

PET/CT is superior than 2-dimensional planar providing a better image quality and enables quantitation of tumor metabolism. Acquisition and fusion of PET with CT also allow for localization and morphologic evaluation of abnormalities, leading to increased specificity. The National Comprehensive Cancer Network (NCCN) guideline recommended PET/CT imaging in cancers with high risk skeletal metastases, PET has advantage than CT in diagnosing osteolytic lesions; but combining PET with CT, increase the detection of osteoblastic lesions.

CT is recommended to evaluate structural integrity in revealing cortical integrity and the extent of structural destruction.

Inclusion Criteria:

• patients diagnosed with different types of malignant tumor, suspected or diagnosed to have bone metastases and will do PET/CT examination
• patients diagnosed with different types of malignant tumor, with accidently discovered bone metastases during PET/CT examination.
• patients conscious to provide informed consent.

Exclusion Criteria:

• pregnant women.
• patients with blood sugar > 200 mg/dL.
• patients unable to sleep in a fixed position for 20 minutes.
• severely ill patients who aren't capable of complying with study procedures or comatose patients.

This study will recruit patients diagnosed with different types of tumors with wide range of age, suspected or diagnosed to have bone metastases, and referred to nuclear medicine unit to perform PET/CT examination, or resulted in to have bone metastases.