Bone cancers Flashcards
True or false: Primary bone tumours are more common than secondary ones.
False
What are the 3 most common primary malignant bone tumours?
1) Osteosarcoma (35%)
- mostly children and YA
2) Chondrosarcoma (25%)
- mostly older px
3) Ewing sarcoma (16%)
- mostly children and YA
What are 3 examples of osteogenic tumours?
1) Osteosarcoma
2) Osteoid osteoma
3) Osteoblastoma
What are 5 examples of cartilage tumours?
1) Chondrosarcoma
2) Chondroma
3) Chondroblastoma
4) Chondromyxoid fibroma (CMF)
5) Osteochondroma
What are 3 types of fibrogenic bone tumours?
1) Fibrous dysplasia
2) Desmoplastic fibroma
3) Fibrosarcoma
What are 2 types of fibrohistiocytic tumours?
1) Benign
2) Malignant
What are 2 types of giant cell rich bone tumours?
1) Benign
2) Malignant
What are 2 types of vascular bone tumours?
1) Angiosarcoma
2) Epithelioid Hemangioendothelioma
What are 2 types of haematopoetic bone tumours?
1) Myeloma
2) Lymphoma
What are 3 typical presentations of primary malignant bone tumours?
1) Pain
2) Mass and swelling
3) Pathological fracture
4) Loss of function
What is the gold standard for diagnosis and typing of bone tumours?
Biopsy (needle or incisional surgical biopsy)
What is the 1st line Ix for bone tumours?
X-ray
What are the benefits of using a MRI/CT for a suspected bone tumour?
Accurately outlines bone tumours and relations with other structure for pre-op assessment/surgery planning
What are the benefits of using a bone radionuclide bone scan for a suspected bone tumour?
Detect tumour spread to other bones
What are the benefits of using a PET scan for a suspected bone tumour?
1) Very sensitive for tumour spread
2) Can infer malignancy esp in post-op follow ups
What are 4 common Ix used for bone tumours?
1) X-ray
2) MRI/CT
3) Bone radionuclide bone scan
4) PET scan
5) Biopsy
What are 4 prognostic factors for primary malignant bone tumours?
1) Size
2) Grade
3) Stage
4) Location and margin clearance
- surgically resectable?
5) Response to chemotherapy (only for osteosarcoma and Ewing sarcoma)
Which of the osteogenic tumours are malignant?
Osteosarcoma
What is a osteosarcoma?
A mostly high-grade malignant bone tumor that produces osteoid directly from tumor cells
Osteosarcoma EPC:
M (</>) F
Age group:
a/w:
M > F
10-25 y/o
older px a/w precursor lesion (eg. paget’s)
What are 4 radiological findings associated with osteosarcoma?
1) Large
2) Destructive
3) Lytic/blastic
4) Permeative margins (may break through cortex and elevate periosteum)
5) Sunburst pattern
Which part of the bone do osteosarcomas usually arise from?
Metaphysis of long bones (eg. distal femur, proximal tibia, proximal humerus)
- Medullary cavity then extends into cortex
What is the histological appearance of osteosarcoma?
Lace-like pattern of OSTEOID - - produced by eosinophilic matrix entrapping anaplastic tumor cells
Which of the chondroid tumours are malignant?
Chondrosarcoma
What is the difference between a chondroblastic osteosarcoma and a chondrosarcoma?
Both malignant but chondrosarcoma cannot produce osteoid (only osteosarcoma can)
Are chondrosarcomas chemosensitive?
No
Chondrosarcoma EPC:
M (</>) F
Age group:
a/w:
M > F
30-60 y/o
a/w pre-existing bone tumours
What are 3 macroscopic features of chondrosarcoma?
1) Large lobulated, pearly white or light blue
2) Focal calcification
3) Myxoid change (suggestive of malignancy)
What are 2 histological features of chondrosarcoma?
1) Permeation of bone trabeculae
2) Soft tissue and marrow invasion
Where do chondrosarcomas commonly metastasise to?
Lungs
Osteochondromas are mainly (solitary/multiple)?
Solitary
- if multiple → usually multiple hereditary exostoses syndrome (EXT1/2 genes)
Do osteochondromas often undergo malignant transfomations?
No
What is a osteochondroma?
Exostosis
- most common benign bone tumours in long bones
- cartilage-capped tumour attached to underlying skeleton by bony stalk
(bone extension containing cortex and periosteum convered by thin cartilaginous cap)
What are 3 types of chondromas?
By location:
1) Enchondroma
- within medullary cavity
2) Subperiosteal chondroma
- bone surface
3) Soft tissue chondroma
- inside soft tissue and no communication with adjacent bone
What are 2 examples of non-hereditary multiple enchrondromas?
1) Ollier’s disease
2) Maffucci syndrome
What are 2 heterozygous mutations that cause both syndromic and solitary enchondromas?
IDH1/2 genes
Giant cell rich lesions of bones and joints are usually (benign/malignant).
All benign with very rare malignant
What is a brown tumour?
Giant cell rich bone tumour a/w hyperparathyroidism
What is pigmented villonodular synovitis?
Giant cell tumour of the joint
What is the most common benign bone tumours arising in long bones?
Osteochondroma
Giant cell tumours of the bone are often benign but ________________________.
Benign but locally aggressive with high rate of recurrence
Giant cell bone tumour EPC:
M (</>) F
Age group:
Demographic:
Mostly (solitary/multiple)
F > M
30-50 y/o
more common in oriental countries
Mostly solitary
Where are giant cell bone tumours most common?
Long tubular bones (esp knee)
- epiphyseal-metaphyseal region
What are 3 histological features of giant cell bone tumour?
1) Abundant giant cells often w numerous nuclei
2) Stromal cells similar to giant cell
3) No osteoid formation
Do giant cell bone tumours often undergo malignant transformation?
Extremely rare
What is fibrous dysplasia?
Benign tumor reflecting a localized developmental arrest
What are 2 forms of fibrous dysplasia?
Monostotic:
- involvement of a single bone (femur, tibia, ribs, jawbones, calvarium, and humerus are most commonly affected)
Polyostotic:
- involvement of multiple bones (Maybe syndromal)
i) Mazabraud syndrome: fibrous dysplasia (usually polyostotic) and soft tissue myxomas.
ii) McCune-Albright syndrome: polyostotic disease, associated with café-au-lait skin pigmentations and endocrine abnormalities, especially precocious puberty
What is an example of an proto-oncogene that can cause fibrous dysplasia?
GNAS1
What is the gross appearance of fibrous dysplasia?
Tan-white and gritty
What are 3 histological features of fibrous dysplasia?
1) Curvilinear trabeculae of woven bone
2) Surrounded by moderately cellular fibroblastic proliferation
3) bone lack prominent osteoblastic rimming
