Osteosarcoma pathophysiology: Difference between revisions
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{{Osteosarcoma}} | {{Osteosarcoma}} | ||
==Overview== | ==Overview== | ||
==Pathophysiology== | |||
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The tumor may be localized at the end of the long bones. Most often it affects the upper end of [[tibia]] or [[humerus]], or lower end of [[femur]]. The tumor is solid, hard, irregular ("fir-tree" or "sun-burst" appearance on X-ray examination) due to the tumor spicules of calcified bone radiating in right angles. These right angles form what is known as [[Codman's triangle]]. Surrounding tissues are infiltrated. | The tumor may be localized at the end of the long bones. Most often it affects the upper end of [[tibia]] or [[humerus]], or lower end of [[femur]]. The tumor is solid, hard, irregular ("fir-tree" or "sun-burst" appearance on X-ray examination) due to the tumor spicules of calcified bone radiating in right angles. These right angles form what is known as [[Codman's triangle]]. Surrounding tissues are infiltrated. | ||
Microscopically: The characteric feature of osteosarcoma is presence of osteoid (bone formation) within the tumour. Tumor cells are very [[pleomorphic]] ([[anaplastic]]), some are giant, numerous atypical [[mitoses]]. These cells produce [[osteoid]] describing irregular [[trabeculae]] (amorphous, [[eosinophilic]]/pink) with or without central calcification ([[hematoxylinophilic]]/blue, granular) - tumor bone. Tumor cells are included in the [[osteoid]] matrix. Depending on the features of the tumour cells present (whether they resemble bone cells, cartilage cells or fibroblast cells), the tumour can be subclassified. Presence of immature blood vessels (sarcomatous vessels lacking endothelial cells) favors the bloodstream metastasizing. | Microscopically: The characteric feature of osteosarcoma is presence of osteoid (bone formation) within the tumour. Tumor cells are very [[pleomorphic]] ([[anaplastic]]), some are giant, numerous atypical [[mitoses]]. These cells produce [[osteoid]] describing irregular [[trabeculae]] (amorphous, [[eosinophilic]]/pink) with or without central calcification ([[hematoxylinophilic]]/blue, granular) - tumor bone. Tumor cells are included in the [[osteoid]] matrix. Depending on the features of the tumour cells present (whether they resemble bone cells, cartilage cells or fibroblast cells), the tumour can be subclassified. Presence of immature blood vessels (sarcomatous vessels lacking endothelial cells) favors the bloodstream metastasizing. | ||
===Genetics=== | |||
==Genetics== | |||
Hereditary syndromes of osteosarcoma have been identified<ref>Wang LL. Biology of osteogenic sarcoma. Cancer J 11:294-305, 2005.</ref>: | Hereditary syndromes of osteosarcoma have been identified<ref>Wang LL. Biology of osteogenic sarcoma. Cancer J 11:294-305, 2005.</ref>: | ||
*[[Rothmund-Thomson Syndrome]] | *[[Rothmund-Thomson Syndrome]] | ||
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==References== | ==References== | ||
{{Reflist|2}} | {{Reflist|2}} | ||
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[[Category:Disease]] | |||
[[Category:Musculoskeletal Disease]] | |||
[[Category:Orthopedics]] | |||
[[Category:Oncology]] | |||
[[Category:Mature chapter]] | |||
Revision as of 13:52, 10 September 2012
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]
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Osteosarcoma Microchapters |
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Diagnosis |
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Treatment |
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Case Studies |
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Osteosarcoma pathophysiology On the Web |
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American Roentgen Ray Society Images of Osteosarcoma pathophysiology |
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Risk calculators and risk factors for Osteosarcoma pathophysiology |
Overview
Pathophysiology
The tumor may be localized at the end of the long bones. Most often it affects the upper end of tibia or humerus, or lower end of femur. The tumor is solid, hard, irregular ("fir-tree" or "sun-burst" appearance on X-ray examination) due to the tumor spicules of calcified bone radiating in right angles. These right angles form what is known as Codman's triangle. Surrounding tissues are infiltrated.
Microscopically: The characteric feature of osteosarcoma is presence of osteoid (bone formation) within the tumour. Tumor cells are very pleomorphic (anaplastic), some are giant, numerous atypical mitoses. These cells produce osteoid describing irregular trabeculae (amorphous, eosinophilic/pink) with or without central calcification (hematoxylinophilic/blue, granular) - tumor bone. Tumor cells are included in the osteoid matrix. Depending on the features of the tumour cells present (whether they resemble bone cells, cartilage cells or fibroblast cells), the tumour can be subclassified. Presence of immature blood vessels (sarcomatous vessels lacking endothelial cells) favors the bloodstream metastasizing.
Genetics
Hereditary syndromes of osteosarcoma have been identified[1]:
- Rothmund-Thomson Syndrome
- RECQL4 gene mutations
- RB1 gene mutations (also implicated in retinoblastoma)
- Li-Fraumeni syndrome
These syndromes are extremely rare within the Osteosarcoma diagnosis, and probably represent less than 0.5% of those diagnosed
References
- ↑ Wang LL. Biology of osteogenic sarcoma. Cancer J 11:294-305, 2005.