Bone cancer

Question 1

why is the most common form of bone cancer?

Answer 1

secondary or metastasized bone cancer
because it has preferred requirements for metastasis:
-richly vascularized
-large

Question 2

primary bone cancer

Answer 2

• less common than secondary/metastasized
• diverse types
• types are differentiated based on histology

Question 3

what is the most common primary bone cancer

Answer 3

Osetosarcoma

Question 4

what does sarcoma mean and what does carcinoma mean

Answer 4

sarcoma= non-epithelial (mesenchyme origin) 
carcinoma= epithelial origin

Question 5

Osteosarcoma

Answer 5

• most common primary tumor
• approx 75% occurs before age 20 (when growing rapidly, high cell proliferation, probability of mutation higher to occur when cells are rapidly proliferating, bone grows until epiphyseal plates form at approx age 30)
• frequently occurs at metaphysis (where cells proliferate)
• may occur in elders with pagets (excessive bone remodeling)
• usually in knee (where causes swelling & pain
• aggressive mets to lungs

Question 6

secondary (metastasized) bone cancer

Answer 6

• common secondary site
• any primary cancer left long enough approx 50% spreads to bone (approx 50% of all cancer spreads to bone) (greater than 85% from breast, lung and prostate)
• pain, swelling & pathologic fractures (avoid fractures because once develops hard to fix)

Question 7

Diagnosing bone cancer

Answer 7

• x-ray, CT, MRI
• bone scans (bone density scan if CT or MRI already giving information wont need more) (the principle of bone density scan is absorption & transmission of light through bone) (objective to determine if bone is porus) (T score lower more porus bone, T score higher less porus bone is)
• biopsy (for type of cancer cell, also for grading & staging)

Question 8

treating bone cancer

Answer 8

• chemo, radiation & surgery
• pain
• prevent fractures

Question 9

what are some of the surgery options with bone cancer

Answer 9

bloc excision- which is removing tumor & some normal tissue (cannot just do this because there is now a hole in the bone. so grafting bone) (THIS IS A LIMB SAVING SURGERY)
-more extreme cases may need to do amputation