1) The document discusses metastatic bone disease, defining it as secondary malignant neoplastic disease resulting from metastasis of a primary tumor to the skeletal system. Common primary sites include breast, lung, thyroid, kidney, and prostate.
2) Metastatic bone lesions can be osteolytic, caused by tumor-secreted PTHrP stimulating bone resorption, or osteoblastic, caused by endothelin 1. A multidisciplinary approach is needed to treat underlying conditions, provide pain relief, and maximize quality of life.
3) Management depends on solitary versus multiple lesions and prognosis. For solitary lesions surgery may be curative, while for multiple lesions the goal is palliation. Risk assessment tools like H
6. Epidemiology
• Aging population = increased incidence of Metastatic bone disease
• Site for mets
• Lung -> Liver -> Bone
• Lytic lesions in patients >40 yrs - MBD should be considered
7. Common sites
• Breast
• Lung
• Thyroid
• Kidney
• Prostate
• Hematological
• commonest site = spine > proximal femur > humerus
8. Pathophysiology
• Paget's Seed & Soil theory
• The 'seeds' (tumor cells) require appropriate 'soil' (the bone micro-
environment) to establish skeletal metastasis
9.
10. Types of lesions
• Osteolytic bone lesions
• Tumor cells secrete PTHrP (PTH related peptide)
• Bone resorption result in release of
• Transforming growth factor-β (TGF- β)
• Insulin-like growth factor-1 (ILGF-1)
• Stimulate tumor cells to multiply and release more PTHrP
• “Vicious cycle”
11. Types of lesions
• Osteoblastic lesion
• Due to tumor-secreted endothelin 1
27. Take home message
• Consider MSD in patients with lytic bonlesions >40yrs
1. Lytic lesion OR fracture
2. Established primary or unknown primary
3. Solitary or Multiple
4. Risk assessment
5. Prognostic scoring
28. Case 1
57yr old lady
left thigh pain
Dx with breast Ca 2yrs ago
Mastectomy + chemo done
How to proceed?
29. Case 2
75yr old gentleman
DM/Hpt
Slipped and fell
How to proceed?
Editor's Notes
Detachment of tumor cellsInvasion of tumour cells into surrounding tissue to reach vesselsIntravasation into vessels lumenEvasion ( Avoidance) of host defense mechanismAdherence to endothelium at remote locationExtravasation from vessels into surrounding tissueSurvival and growth within the tissueEstablish own blood supply