*Causes of Osteolytic metastasis :
- Kidney (expansile) and Thyroid : Expansile lytic osseous metastasis are characteristic of Renal cell carcinoma (kidney) and Thyroid .
- Gastrointestinal tract (GIT)
- Breast (occasionally)
- Less commonly melanoma, carcinoma of bronchus and pheochromocytoma may also present with Expansile lytic lesions.
*Causes of Osteoblastic metastasis :
- Breast (may be mixed)
- Neurogenic tumors