L19- Tumors of Bone Flashcards
why are the incidences of primary bone tumors unknown
- most tumors are benign
- most are asymptomatic –> incidental findings
- biopsies are mostly not performed
(1) and (2) are the most common malignant bone tumors
1- metastasis, secondary tumor
2- sarcomas
bone tumors most commonly affect (long/flat/irregular) bones- indicate specific location in bone
long bones at metaphysis (very few epiphysis, diaphysis)
describe the general symptoms of bone tumors
Benign: asymptomatic
Malignant: aggressive
- pain
- pathological fracture
- metastases (to non-bone locations)
describe the general gross features of benign bone tumors
- small (usually)
- well-circumscribed
- ‘scalloped border’ (smooth, wavy)
- no destructive growth
- no invasion of other tissues or joints
benign bone tumors are more typical in (older/younger) populations
malignant tumors typically have (good/poor) prognosis
1- younger patients
2- poor prognosis - high grade and highly aggressive tumors
Osteoid Osteoma:
- (1) affected age group
- (males/females) affected more
- (3) are the main affected bones
- (4) is the key sign in clinical presentation
(benign bone forming tumor) 1- young adults, 10-35 y/o 2- males > females 3- appendicular skeleton, mainly femur 4- nocturnal pain alleviated with aspirin
Osteoid Osteoma:
- (1) definition
- (2) three important characteristics
1- benign osteoid producing neoplasms
2:
- small size
- self-limited growth
- usually causes extensive reactive changes in adjacent tissues
Osteoid osteomas changes create a unique lesional tissue termed (1), which is (2) in size. (3) usually surrounds (1). Tumor cells will also produce (4), which is clearly evident on histology.
1- nidus
2- <1cm
3- dense reactive sclerosis
4- irregular trabeculae of woven bone
Osteoma, aka (1):
- (benign/malignant)
- (3) typical size
- usually affects (4) part of bone, mostly in (5) types of bones
- osteomas are apart of (6) if associated with clonic adenomas
1- bone island 2- benign bone forming tumor 3- small growths on bone 4- mature bone (woven) 5- craniofacial bones (skull- on inner or outer surface) 6- Gardner's syndrome
define Gardner’s Syndrome generally
- multiple colonic adenomas
- multiple osteomas (benign)
(1) is the most common bone sarcoma. It usually affects people in the (2) age group. It usually affects the following bones, (3).
Osteosarcoma, 20% of sarcomas
- elderly: flat bones (Paget’s, radiation are risk factors)
- children: long bones, metaphysis (usually around knee: lower femur, upper tibia)
Osteosarcoma:
- (1) hereditary risk factors
- (2) sporadic risk factors
1:
- p53 mutations (Li-Fraumeni)
- retinoblastoma
2:
- P53 mutations
- Rb mutations
- MDM2 (inactivates p53 apoptosis capacity)
determine the grade of Osteosarcoma based on location in the affected bone
Intramedullary - low grade
Intracortical - high grade
Juxtacortical - low or high grade
briefly describe the main histological features of osteosarcoma, separate by grade
malignant tumor cells (highly dysplastic cells) –> depositing lace like osteoid
I- mild cytologic atypia
II- intermediate cytologic atypia
III- high grade, pleomorphic cytological atypia
osteoblastic, chondroblastic, fibroblastic histology
