List eight causes of focal extraosseous uptake

1. Poor radiopharmaceutical preparation (free Tc-99m seen in salivary glands, thyroid gland, and stomach)
2. Reduced, hydrolyzed Tc colloid (activity in liver and bone marrow)
3. Recent nuclear medicine examination (location depends on agent)
4. Primary tumors (e.g., osteosarcoma, neuroblastoma, breast carcinoma, menin-gioma) in the absence of metastatic disease
5. Metastatic deposits from breast tumors, ovarian tumors, gastrointestinal tumors, lung tumors, or osteosarcoma
6. Myositis ossificans
7. Hematoma
8. Some inflammatory processes, such as mastitis