A metastatic bone disease is said to occur when metastases spread to the bone. After lung and liver, bone is considered to be the third most common organ involved by metastases. In breast cancer, the bone is the second most common site for metastases.
Metastases in bone need early detection and aggressive management.
Aims of the treatment in metastatic bone disease are
- Pain relief
- Preservation/restoration of the function
- Local tumor control
- Skeletal stabilization
The metastatic spread to the bone is hematogenous and therefore affects vascularised parts especially the axial skeleton.
The patient with metastatic bone disease metastases may present by any of the following
- Pathological fracture
- Hypercalcemia of malignancy
- Neurological deficit in case of vertebral involvement
- Detailed clinical history
- A high index of suspicion
- Clinical examination
- Radio imaging – Plain radiographs, CT, MRI as required
- Bone Scan
- Hematological investigations – Would be guided by patient profile
- PTH level
- Serum electrophoresis
- Bence Jones proteins
- Biochemical markers for malignancy
- Chest radiographs
- Skeletal survey
- CT guided biopsy
- Open biopsy
Positron emission tomography is helpful in evaluating response to chemotherapy and treatment guidance.
Angiography is used in vascular or very large tumors or aneurysmal bone cysts to identify the feeder vessel or embolize it preoperatively.
Treatment of Metastatic Bone Disease
There are three approaches to metastases and role of each would depend on the type of metastatic tumor, location, and extent of metastases.
- Systemic Therapy
- Bone marrow transplant
- Hormone therapy
Radiotherapy is done for suppression of tumor growth and pain relief.
Surgery is done either for removal of tumor or fixation of pathological fractures or to carry out amputation in case of unsalvageable limbs. In case of the joint is destroyed by a tumor or needs to be taken out, endoprosthesis or arthrodesis is considered.