Bone/Soft tissue Malignancy Flashcards
What is a sarcoma?
Malignant Connective tissue tumor
What is the eipdemiology of malignant bone tumours?
Generally young adults/chidlren
What is the most common site of bone tumours?
Generally around knee, but different for different types of tumours
What is the initial investigation in an suspected bone tumour?
What are the expected findings?
X-Ray
- Lytic features
- extention of bone into soft tssue
What is the gold-standard for diagnosis of sarcomas?
Biopsy
- core Needle biopsy under radiological guidance
What are differentials for bone tumours?
- fibrous dysplasia
- Metaphyseal fibrous cortical defect
What is fibrous dysplasia?
Genetic mutation causing fibrous, weak tissues being layed down instead of mature bone
What is the epidemiology of Fibrous dysplasia
Usually F>M (because of McCune Albright syndrome is 10:1 F:M)
Presentation
- <10 if McCUne Albright syndrome (polyostic)
- 20-30 if single bone involved
What is McCune Albright syndrome?
A genetic syndrome caused by a G-protein activating mutation and subsequent continuous stimulation of endocrine functions
Causes Café au lait spots, fibrous dysplasia + endocrine dysfunctions
What is the commonest site of lesions in Fibrous dysplasia?
Can be any bone
More common
- Rib + proximal femur
X-ray shows a soap bubble osteolysis and Shepherd’s crook deformity - what disease is it likely to be?
Fibrous dysplasia
Shepherd’s crook deformity: coxa varus angulation of the proximal femur, classically seen in femoral involvement
A Bone histology shows chinese letters - what is the likely diagnosis going to be?
Fibrous dysplasia
What is an osteochrondroma?
Benign bone and Cartilage tumour
Most common benign bone tumours
What is the preferred site of osteochondroma?
Bone histology of a lesions shows
Cartilage capped “mushroom” bony outgrowth - what is the diangosis?
Osteochondroma
Show’s normal bone covered by cartilage
What is and enchondroma?
Benign tumour originatign from cartilage
What is the most common site for Enchondromas?
Usually presents in Hands (45%)
What does histology of an enchondroma show?
Normal cartilage
Calcified matrix
X-ray shows a Lytic lesion
Cotton wool calcification
Expansile and O ring sign - what is the likely diagnosis?
Enchondroma
Can overall look malignant on X-ray
What is a Giant Cell tumour?
What is the epidemiology?
It is a borderline-malignant tumour (of bone, derived from the bone marrow) (usually locally agressive, but even though can metastasise, does not have to)
Usually in 20-40yo
F>M
What are histological findings of a Giant cell tumour?
Osteoclasts and stromal cells (stromal cells are the malignant cells, but many osteoclasts giant cells seen)
“Soap bubble appearance”
“Giant multi-nucleate osteoclasts (Arrow)
What is the x-ray appearance of a giant cell tumour?
Lytic/lucent lesions right up to articular surface (usually non-invasive)
What is the usual distribution of metastatis bond tumours?
Usually do not go below the elbow or below the knee
It depends on the age group + primary malignancy
What is the site distribution of Giant cell tumour?
Commonest Knee-epiphesis
What are 5 common adult tumours that metastasis to bone?
Breast
Prostate
Lung
Kidney
Thyroid
What are 5 common childhood tumours that metastasise to bone?
- Neuroblastoma
- Wilm’s tumour
- Osteosarcoma
- Ewings
- Rhabdomyosarcom
What is the site predelection of Osteosarcoma?
Majoirty ends of long bones (lower femur
What is the epidemiology of osteosarcomas?
Peak in adolescencse (75% <20)
What are histological findings of osteosarcomas?
Malignant mesenchymal cells
ALP +ve
Replacement of bone marrow with trabecular bone
What are x-ray findings of osteosarcomas?
Elevated periosteum (Codman’s triangle- image)
Sunburst appearance
What factors are used for the classification of osteosarcomas?
- Site within bone
- Differentiation
- Multicentricity
- Primary or secondar (metastasised)
What is the prognosis of Osteosarcomas?
Overall poor - 5 year survival <60%
What is the epidemiology of a chondrosarcoma?
Malignant cartilage producing tumour
Usually >40
What is the site preference of chondrosarcomas?
Axial skeleton Femur/tibia/ pelvis
What are X-ray findings of chondrosarcomas?
Lytic lesion with fluffy calcification
What is the prognosis of chondrosarcoma diagnosis?
70% 5y survival (depends on grade & size)
What is the histological presentation of chondrosarcomas?
Malignant chondrocytes (proliferation of cartilage)
What is an Ewing’s sarcoma?
High malignant small round cell tumours (arising from neuroectodermal cells)
What is the epidemiology of ewin’s sarcoma?
Usually young (<20)
What is the site of ewing’s sarcoma?
Usually in long bones + pelvis
What is the x-ray appearance of Ewin’s sarcoma?
Onion skinning of periosteum
What is the histological appearance of ewing’s sarcoma?
What molecular test are doing to confirm the diagnois?
Sheets of small round cells CD99 +ve
T 11:22 translocation
A lot of other small-cells tumours will need to be excluded by immunohystophenotyping before diangosis
What is a tumour of fat?
Liposarcoma
What in an osteoma?
What ist the histological appearance?
Bony outgrowths attached to normal bone
Histologically:normal bone
What is Gardner syndrome?
GI polyps + multiple osteomas + epidermoid cysts
What is an osteoid osteoma?
Small benign bone forming lesion,
Histologically is normal bone (arising from osteoblasts)
night pain relieved by aspirin
What are common x-ray findings in Osteoid osteomas?
Central nidus (luscent)
with sclerotic rim (opaque) ‘Bull’s-eye’
