Pathology

Question 1

Achondroplasia is the reduction in proliferation of __1_ in developing growth plate; failure of normal ____2_____ formation

Answer 1

1. chondrocytes

2. epiphyseal cartilage

Question 2

Cause of achondroplasia (mutation?)

Answer 2

defect in signal transduction - point mutation involving gene coding of FGFR3 in cell signaling

Question 3

what zones in achondroplasia are narrowed and disorganized –> no columns

Answer 3

zones of proliferation and hypertrophy

Question 4

abnormality in OI

Answer 4

type I collage synthesis - mutations in genes that code for alpha1 and alpha2 chains

Question 5

how is OI inherited

Answer 5

AD

Question 6

For major subtypes of OI - which one is which type?

1. lethal - multiple fracture in utero
2. survive fractures in infancy but have progressive deformity
3. increased risk of fracture but no deformity

Answer 6

1. type II
2. type III and IV
3. type I

Question 7

type of OI where you would see blue sclera, increased risk of fractures, and dental and hearing problems

Answer 7

type I

Question 8

disease causes by decreased osteoclastic bone resorption –> diffuse skeletal sclerosis

abnormally thickened, heavily mineralized, abnormally brittle bone

Answer 8

Osteopetrosis

Question 9

what osteopetrosis form is malignant and which is benign?

Answer 9

AR = malignant

AD = benign

Question 10

what may you see clinically with osteopetrosis?

Answer 10

increase incidence of fractures

anemia

thrombocytopenia

increase susceptibility of infections

cranial nerve roots may be compressed –> cranial nerve palsy

Question 11

What may be a helpful treatment for someone with osteopetrosis

Answer 11

bone marrow transplant

Question 12

disorder where the cortex and trabeculae are thinned, but remain of normal composition

quantitative loss of bone

Answer 12

osteoporosis

Question 13

what is primary osteoporosis related to?

Answer 13

age

menopause

Question 14

Osteoporosis is worse in areas containing abundant ___ bone such as weight-bearing bones

Answer 14

trabecular

Question 15

Osteoporosis will have a increase in _1__ of bone due to decrease in bone mass. There will be fewer and thinner _2__; do not join to form trabeculae

Answer 15

1. Porosity

2. bony spicules

Question 16

What are the 2 main vertebral fracture patterns of osteoporotic bone?

1. anterior column of vertebral body is compressed leading to kyphosis, but usually with preservation of the spinal cord.
2. an axial load disrupts the anterior, middle, and/or posterior columns leading to disruption of the spinal cord

Answer 16

1. Wedge fractures

2. burst fractures

Question 17

Rickets/osteomalacia is defective _________ caused by vitamin D deficiency

Answer 17

matrix mineralization

Question 18

function of vitamin d

Answer 18

maintain adequate levels of calcium and phosphate for bone mineralization

Question 19

What are the effects rickets has on children?

Answer 19

1. heaping of unmineralized matrix; inadequate provisional calcification of epiphyseal cartilage
2. softening of bones –> fractures and deformities
3. inadequate maturation of cartilage

Question 20

Most common causes of rickets/osteomalacia

Answer 20

Malabsorption syndrom

Inactive activation of vitamin D

(also: dietary deficiency of vit. D, inadequate vit. D synthesis, inborn error of vitamin D metabolism

Question 21

generalized pain, fractures, mottled areas of lucency (pseudofractures) in bones are symptoms of what?

Answer 21

osteomalacia

Question 22

Symptoms of rickets

Answer 22

loss of rigidity including:

1. bowing of legs, 2. enlarged costochondral junctions (rachitic rosary),
2. pigeon breast deformity,
3. kyphosis,
4. frontal bossing

Question 23

what disorder produced bone cysts and brown tumors

Answer 23

hyperparathyroidism

Question 24

what does PTH do

Answer 24

1. activates osteoclast to resorb born, mobilizes calcium
2. increase resorption of calcium by renal tubules
3. increase synthesis of active Vit. D by kidneys –> enhanced calcium absorption from gut

Question 25

what happens if have hyperparathyroidism

Answer 25

significant skeletal changes secondary to abnormal osteoclastic activity to increase serum calcium and phosphate

Question 26

term describes collectively all of the skeletal chainges of chronic renal disease

Answer 26

renal osteodystrophy

Question 27

pathophysiology of renal osteodystropy

Answer 27

First: renal failure --> decrease 1,25-(OH)2-D3 --> hypocalcemia --> secondary hyperparathyroidism Second: osteitis fibrosa cystica metabolic acidosis, iron and aluminum deposits in bone interfering with matrix mineralization --> osteomalacia

Question 28

disorder of bone maintenance - acceleration of bone turnover --> increase bone mass of poorly structures and weak bone 1. aggressive osteoclast-mediated bone resorption 2. imperfect osteoblast-mediated bone repair

Answer 28

Paget disease

Question 29

what virus like particles and antigens were identified in osteoclasts of Paget disease

Answer 29

Paramyxovirus

Question 30

what part of the bone dose Ewing sarcoma occur

Answer 30

diaphysis

Question 31

what part of the bone does chondrosarcoma occur

Answer 31

metaphysis

Question 32

what part of the bone does osteosarcoma occur

Answer 32

metaphysis

Question 33

what part of the bone does giant cell tumor occur

Answer 33

epiphysis

Question 34

rare benign tumor of mature bone - asymptomatic

Answer 34

osteoma

Question 35

site of osteoma

Answer 35

cortical bones of skull and face

Question 36

Xray - bone tumors where central area of tumor (nidus) is radiolucent, surrounded by rim of sclerotic bone

Answer 36

osteoid osteoma osteoblastoma

Question 37

How do osteoid osteoma and osteoblastoma differ (have identical histology) in regards to pain and size?

Answer 37

Osteoblastoma - giant osteoid osteoma (>2 cm) - painful - not relieved with aspirin Osteoid osteoma - smaller - painful - relieved with aspirin

Question 38

where is osteoblastoma found?

Answer 38

vertebral column

Question 39

age osteoblastoma affects

Answer 39

teens-twenties

Question 40

what is this the histology of? - interlacing trabeculae of woven bone surrounded by osteoblasts; loose CT stroma (no BM elements); may see giant cells

Answer 40

Osteoblastoma Osteoid osteoma

Question 41

malignant mesenchymal tumor; neoplastic cells produce osteoid; sometimes makes cartilage

Answer 41

osteosarcoma

Question 42

bone tumor with bimodal age distribution: most occur <20 but small peak in elderly with predisposing conditions

Answer 42

osteosarcoma

Question 43

where does osteosarcoma usually metastisize to? (AGGRESSIVE)

Answer 43

lungs | also bone, liver, other

Question 44

Treatment for osteosarcoma?

Answer 44

pre-op chemo radical surgery or limb salvage surgery and chemo

Question 45

What kind of bone tumor: large destructive mixed blastic and lytic mass with infiltrating margins, Codman triangle destroys cortex, extends inwards --> marrow cavity extends outwards --> adjacent soft tissues

Answer 45

osteosarcoma

Question 46

what bones are osteosarcomas most often found

Answer 46

knee

Question 47

elevation of periosteum to produce an angle between surface of involved bone What bone tumor would you see this in?

Answer 47

Codman triangle Osteosarcoma

Question 48

what age would you see osteochondroma; what gender?

Answer 48

young (10-30) males (x3)

Question 49

what tumor would you expect if the xray showed polypoid growth (mushroom-shaped)

Answer 49

osteochondroma

Question 50

how do you treat osteochondroma

Answer 50

excision

Question 51

Benign tumor of hyaline cartilage, well circumscribed

Answer 51

chondroma in medullary cavity called enchondromas

Question 52

what is it called if there are multiple enchondromas

Answer 52

Ollier disease

Question 53

common site of condromas

Answer 53

solitary, metaphyses of small bones of hands and feet

Question 54

X-ray shows well defined bone with stippled calcium - what is it?

Answer 54

chondroma

Question 55

chondromas affect what age

Answer 55

young - 20 to 40

Question 56

Microscopy: mature, hypocellular cartilage with bland chondrocytes what is it?

Answer 56

chondroma

Question 57

when is there a worse prognosis for chondroma

Answer 57

if multiple chondroma syndrome (Ollier) - 1/3 develop chondrosarcoma

Question 58

where are chondrosarcomas found

Answer 58

pelvic bones, axial skeleton

Question 59

what determines the grade (1-3) of chondrosarcoma?

Answer 59

cellularity degree of nuclear atypia mitotic activity

Question 60

small round blue tumors primitive neural tumors derived from a precursor multipotent mesenchymal stem cell

Answer 60

Ewing sarcoma (EWS) PNET

Question 61

how do EWS and PNET differ

Answer 61

Both have neural phenotypes and identical chromosome translocation EWS --> undifferentiated PNET --> neural differentiation

Question 62

sheets of uniform, undifferentiated small round blue cells

Answer 62

Ewing sarcoma

Question 63

Homer wright rosettes with central fibrillary cores

Answer 63

PNET

Question 64

Numerous osteoclast-like multinucleated giant cells mixed with mononuclear stromal cells

Answer 64

giant cell tumor of bone (osteoclastoma)

Question 65

where do most giant cell tumor of bone arise

Answer 65

epiphyses of long bones around knee; proximal humerus and distal radius

Question 66

age of giant cell tumor of bone

Answer 66

20-55 (mature bone)

Question 67

what tumor of the bone may present with arthritis symptoms

Answer 67

giant cell tumor of bone

Question 68

age group for fibrous dysplasia

Answer 68

young 10-30

Question 69

what does xray look like for fibrous dysplasia

Answer 69

radiolucent in diaphysis

Question 70

Morphology is showing curvilinear spicules of immature woven bone (chinese characters) surrounded by fibroblastic proliferation what is it

Answer 70

fibrous dysplasia

Question 71

what does fibrous dysplasia result from

Answer 71

somatic mutation occurring during embryonic development

Question 72

what bone tumors are malignant

Answer 72

All sarcomas giant cell tumor