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62 Cards in this Set
- Front
- Back
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what suffix do malignant tumors usually have |
-sarcoma |
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how are bone tumours classified? |
according to what type of matrix is produced |
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what does a tumour with prefix osteo mean |
they secrete osteoid - bone always woven, never lamellar -bone contains a lot of CT and vascular elements |
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what does a tumour with prefix chondro mean |
tumour produces cartilage |
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what does prognosis depend on |
stage- how big is the tumour, how many lymph nodes involved, how many other metastases grade- what it looks like under microscope |
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where do osteomas project |
from the subperiosteal surface of the cortex - on or inside skull or facial bones |
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when are osteomas usually detected |
middle age |
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what does an osteoma look like |
woven and lamellar bone deposited in a cortical pattern with haversian like systems -some contain trabecular bone with hematopoietic marrow |
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when are osteomas dangerous |
when the impinge on an eye or cranial nerve |
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what are the similarities between osteoid osteomas and osteoblastomas |
-similar histology- osteoid osteomas smaller (less than 2cm) -both affect mostly males under 25 yrs ` |
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where are osteoid osteomas found |
appendicular skeleton (femur and tibia) |
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where are ostemoblastoma found |
posterior parts of spine |
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what is an osteoid osteoma |
randomly interconnecting trabeculae of woven bone that are prominently rimmed by osteoblasts |
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what do osteoid osteomas look like |
loose CT surrounding neoplastic bone contains dilated and congested capillaries -well-defined margins, benign cytologic features -reactive bone formation encircles the lesion |
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what does the actual tumour look like in osteoid osteomas |
called nidus - manifests radiographically as a small round lucency that may be centrally mineralized |
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what are the clinical features of bone-forming tumours |
severe bone pain can occur or can be dull and aching -> aspirin works for osteoid osteoma, not osteoblastoma -->pain worse is osteoid osteoma |
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how are bone-forming tumours treated |
radio ablation and surgical excision |
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what is osteosarcoma |
malignant mesenchymal tumour in which the cancerous cells produce bone matrix |
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whats the most common primary malignant tumour of the bone |
osteosarcoma |
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what age do osteosarcomas affect |
bimodal age distribution 1. 75% in persons younger than 20 yrs old 2. rest in the elderly |
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what gender do osteosarcomas affect |
men more common |
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what area of the bone do osteosarcomas typically arise in |
the metaphysical region of long bones of extremities 50% in the knee (also hip, shoulder, jaw) |
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what kind of acquired genetic abnormalities do osteosarcomas have |
policy changes and chromosomal aberrations RB, p53, p16 |
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whats the most common subtype of osteosarcoma |
found in the medullary region of the metaphysis and is poorly differentiated ->large, gritty-poking tumours with areas of hemorrhage and cystic degeneration ->destroy the medullary cavity and frequently the cortex ->cells bizarre looking with large nuclei, lace-like trabecular bone deposited |
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in osteosarcoma what is it called when cartilage is deposited |
chondroblastic osteosarcoma |
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what are the clinical features of osteosarcoma |
-painful, progressively enlarging mass, can present acutely as a fracture -->radiographs often show the tumour lifting periosteum off underlying cortical bone |
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whats codman's triangle |
when the tumour lifts the periosteum off the underlying cortical bone |
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what is the prognosis of osteosarcoma |
without detectable metastases- survival is 66-70 with chemo and surgery with detectable metastases- 20% 5 year survival |
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what is an osteochondroma (exostosis) |
a benign cartilage capped tumour that is attached to the underlying skeleton by a bony stalk |
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whats the most common benign cartilage capped tumor |
osteochondroma |
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what is multiple hereditary exostosis syndrome |
autosomal dominant disease -germline loss of function mutation in EXT1 or EXT2 genes -encode proteins that function in the biosynthesis of heparin sulfate proteoglycans (results in defective endochondral ossification) |
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who does osteochondroma typically affect |
late adolescence/early adulthood men affected three times more often than woman |
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where does osteochondroma typically develop |
bones of endochondral origin and arise from metaphysis near growth plate of long tubular bones, especially the knee (occasionally the pelvis, scapula, ribs) |
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what does osteochondroma look like |
sessile or mushroom shaped -range from 1 to 20 cm -cap composed of benign hyaline cartilage varying in thickness and covered peripherally by perichondrium -->cartilage has appearance of disorganized growth plate and undergoes enchondral ossification, with newly made bone forming inner portion of head and stalk -->cortex of the stalk merges with the cortex of the host bone so that the medullary cavity of the osteochondroma and bone are in continuity |
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what are the clinical findings for osteochondroma |
slow growing masses- only painful if they impinge on a nerve or if stalk becomes fractured -->usually stop growing when growth plates close |
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what are chondromas |
benign tumours of hyaline cartilage that usually occur in bones of endochondral origin (long, tubular) |
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where do chondromas arise |
enchondromas- arise within medullary cavity subperiosteal or juxtacortical chondroma- on the surface of the bone |
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what are the most common intraosseous cartilage tumours |
enchondromas |
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where are the favoured sites of enchondromas |
short tubular bones of the hands and feet |
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what do enchondromas look like |
smaller than 3cm -well circumscribed nodules of benign hyaline cartilage -->peripheral portion of the nodules may undergo endochondral ossification |
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what are the clinical features of enchondromas |
usually painless- rarely present with pain and pathological fracture can be quite large |
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what are the different types of chondrosarcoma |
1. conventional (hyaline or mixed) 2. clear cell 3. dedifferentiated 4. mesenchymal |
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whats the most common type of chondrosarcoma ` |
conventional central (within the medulla) tumour |
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whats the second most common malignant bone tumour |
chondrosarcoma |
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does chondrosarcoma affect males or females more often |
males |
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what do conventional chondrosarcomas look like |
malignant hyaline and myxoid cartilage -large, bulky tumours made up of nodules of gray white, glistening tissue -spotty calcifications are typically present, central necrosis may create cystic spaces -degree of anaplasia may vary within the tumour and different histological types may also be present within the same tumour |
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what are the clinical features of chondrosarcoma |
-arise in axial skeleton or central portions of the skeleton (ribs, hips, shoulder), proximal appendicular -painful, progressively enlarging masses -slow growing tumours cause reactive bone thickening -fast growing tumours tend to erode the cortex and cause pathologic`cal fractures |
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whats the prognosis for chondrosarcoma |
tend to have good prognosis -most histological grade 1 (90% 5 year survival) |
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what are fibrous cortical defect and non-ossifying fibroma |
fibrous cortical defects found in 30 to 50 percent of children older than 2 yrs -->believed to be developmental defects rather than neoplasms |
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how do fibrous cortical defects arise |
eccentrically in the metaphysics of the distal femur and proximal tibia and almost half are bilateral or multiple |
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what do fibrous cortical defects look like |
elongated, sharply demarcated radiolucencies surrounded by a thin rim of sclerosis -grey to yellow-brown cellular lesions containing fibroblasts and macrophages |
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what kind of pattern are the fibroblasts arranged in in fibrous cortical defects |
storiform (pinwheel) pattern |
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whats the outcome of fibrous cortical defects? |
limited growth potential- undergo spontaneous resolution within several years, being replaced by normal cortical bone -->few enlarge into non-offifying fibromas that present with pathologic fracture |
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what is ewing's sarcoma |
2nd most common bone sarcoma in children |
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who does it affect |
children 10-15 yrs old 80% under 20 |
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whats a subtype of ewings sarcoma |
PNET - primitive neuroectodermal tumor - more differentiated form of ewings sarcoma |
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where does ewings sarcoma arise |
in the medullary cavity and invades the cortex, periosteum, soft tissue |
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what does ewings sarcoma look like |
-tumor is soft, tan-white, frequently contains areas of hemorrhage and necrosis -sheets of uniform, small, round cells that are slightly larger than lymphocytes -scant cytoplasm -generally little stroma -necrosis may be prominent, few mitotic figures |
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what are the clinical features of ewings sarcoma |
-usually arise in the diaphysis of long tubular bones, especially femur and flat bones of pelvis -present as painful enlarging masses, affected site frequently tender, warm, swollen -->some people have fever, anemia, etc |
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what do plain radiograms show in ewings sarcoma |
destructive lytic tumour that invades surrounding tissue -->produces layers of reactive bone being deposited in an onion skin fashion (layers upon layers) |
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what is the prognosis and treatment of ewings |
treatment is chemotherapy and surgical excision 75% 5 year survival |
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what are giant cell tumour |
multinucleate |
