10: Pathology - malignant tumours Flashcards
How are MSK tumours discovered?
Examination
Radiology
Sarcomas are (more / less) common than carcinomas.
less common
What is a lipo(sarco)ma?
Tumour of adipose tissue
What is a leio(sarco)ma?
Tumour of smooth muscle
What is a rhabdomyo(sarco)ma?
Tumour of skeletal muscle
How are MSK tumours staged and identified?
Biopsy
Primary MSK tumours often have a ___ cause.
genetic
What are genetic studies used in the diagnosis of genetic MSK diseases?
Karyotyping
FISH (fluorescence in-situ hybridisation)
FISH allows chromosomal ___ to be visualised.
translocations
What is immunohistochemistry?
Target protein pigmented
If tumour cell produces target protein, it will light up
What are characteristic traits of MSK tumours which aid in their identification?
Age group affected
Common sites (e.g the knee)
Appearance on radiology and histology
Which group of people review patient cases before treatment is started?
MDTs
What are some common benign lesions of connective tissue and bone?
Osteochondroma
Enchondroma
Cysts (bone cysts, ganglion cysts)
Giant cell tumours
Fibrous dysplasia
Fibromatosis
Where are ganglion cysts commonly found?
Joint capsules - fingers, wrists, knees
Ganglion cysts are herniations through the tendon ___.
sheathe
Are ganglion cysts true cysts?
No, don’t have an epithelial lining
Why are ganglion cysts hard?
Fibrous tissue
What are some examples of fibromatoses?
Dupuytren’s contracture (thickening/sclerosis of palmar fascia)
Knuckle pads
Plantar fascia
Penile fascia - Peyronie’s disease
dupuytren’s - association with alcohol + a ton of other things
Fibromatoses all involve the formation of dense, contracted ___ tissue histologically.
They are (benign / malignant).
fibrous
benign
Fibromatoses can be superficial or ___.
deep
Where generally are giant cell tumours commonly found?
Bone
Tendons
Joints
What do giant cells look like under the microscope?
Big
Multi-nucleate
Giant cell tumours are (benign / malignant).
benign
What are benign tumours of fat called?
Lipomas
Where are the nuclei of adipose cells found?
Periphery
What are benign tumours found in the forearms of young people which tend to be painful?
Angiolipoma
angel?
benign, painful lumps
How do liposarcomas look compared to lipomas under the microscope?
Presence of lipoblasts - dark purple blobs - among the adipocytes
Where are leiomyomas - benign tumours of smooth muscle - commonly found?
Uterus
What is a malignant smooth muscle tumour called?
Are they common?
Leiomyosarcoma
No
Which technique, involving protein tagging, is used to identify leiomyosarcoma?
Immunohistochemistry
What are tumours of skeletal muscle called?
In which group are they commonly found?
Rhabdomyo(sarco)ma
Children
What are tumours of cartilage called?
Chondro(sarco)ma
What is a common benign cartilaginous tumour found in the smaller bones e.g digits?
Enchondroma
Cartilaginous tumours found in the appendicular skeleton tend to be ___.
Cartilaginous tumours found in the axial skeleton tend to be ___.
appendicular - benign
axial - malignant
osteomas - cranial bones
gardner’s syndrome
Where do osteoid osteomas tend to occur?
Long bones
Halo-appearance, extremely painful, young people
How is the pain associated with osteoid osteomas treated?
NSAIDs (aspirin, ibuprofen)
Osteoid osteomas are (benign / malignant).
benign
What is the characteristic histological appearance of osteoid osteomas?
Halo (nidus), spongy bone surrounded by hard bone
What is a malignant bone tumour called?
Which age group is usually affected?
Which bones are usually affected?
Osteosarcoma
Young people
Long bones
Any tumour producing osteoid (pink stuff on histology) should be treated as an ____.
osteosarcoma
What is a common genetic condition causing malignant bone tumours?
Ewing’s sarcoma
Which age group tends to develop Ewing’s sarcoma?
Which bones are affected?
What is the genetic cause?
Young people
Long bones
Translocation of chromosomes 11 and 22, t(11;22)
What does Ewing’s sarcoma look like on microscopy?
Small round blue cells
resembles a lot of other things
Ewing’s sarcoma grow rapidly to enormous sizes, raising the ___ off the bone.
periosteum
MSK tumours common in older people are ___ from other organs.
metastases
figure out what sarcomatoid carcinomas are
What is a pseudotumour?
Something that seems like a neoplasm but isn’t actually
nodular fasciitis
commonly confused for malignancy
What is myositis ossificans?
What does it commonly occur following?
Ossification of muscle
Trauma
