Malignant disease of the Bone Flashcards
Is Primary malignancy of the bone common?
relatively rare in the UK.
~550 cases per year.
what is the 10 year survival rate for primary bone malignancy?
~55%.
Most patients who die from bone sarcoma are >70 years old.
What can Bone sarcoma be divided into?
Osteosarcoma
Ewing’s Sarcoma
Chondrosarcoma
what are primary malignancy of the bone are referred to as?
sarcoma
Reflect the connective tissue origin.
what is the tissue origin of an Adenoma?
glandular (usually epithelial)
what is the tissue origin of an Neuroblastoma?
neural
what is the tissue origin of an Germinoma?
germ cells
~30% of bone sarcoma are associated with what kind of sarcoma?
osteosarcoma.
what age is associated with osteosarcoma?
This form of sarcoma is mostly associated with young age of onset
Teenagers.
Due to rapid growth during teenage years. Loads of growth signals. If something goes wrong growth can go out of control and become cancer
where do the tumour tends to develop?
in the knee regions (usually around the metaphysis of long bones)
~60%
Knee has most impact, wear and tear from walk and add growth hormones of teenage years
What causes Osteosarcoma?
Aetiology of osteosarcoma is unclear but several factors have been identified:
Cancer pre-disposing syndromes.
Bone dysplastic conditions (Pagets)
Familial osteosarcoma.
Radioactive isotopes (particularly strontium-90)
what is Paget’s Disease?
Condition characterised by excessive breakdown and reformation of bone.
Bone remodelling is disorganised.
common complication of paget’s disease?
Weakens the affected bone.
Fractures are common.
what viral infections are associated to cause Paget’s?
Measles.
Respiratory syncytial virus.
which genetic mutations are causes of Paget’s?
.P62 mutations.
What is P62 (or sequestome 1)?
is a protein which targets other proteins for destruction.
Binds to other proteins and causes them to be ubiquinylated.
How can it be mutated in Paget’s?
Can be mutated in Paget’s causing proteins to not be destroyed.
Osteoclasts become inappropriately activated.
Treatment of Paget’s should be limited to specific individuals.
What clinical aspects are considered?
Danger of nerve involvement.
Involvement of weight-bearing joint.
Significantly symptomatic.
which treatments can be used?
Bisphosphonates are useful.
risedronate – a tablet taken once a day for 2 months (30mg)
zoledronate – a one-off injection (5mg)