MSK path IV Flashcards
tumor with schwann cell differentiation
peripheral nerve sheath tumor
3 common types of peripheral nerve sheath tumor
schwannoma
neurofibroma
malignant peripheral nerve sheath tumor
peripheral nerve sheath tumors are assoc with what familial tumor syndromes
NF I, NF II, schwannomatosis
what is a consistent finding in all schwannomas
loss of expresion of NF 2 that produces merlin
schwannomas
benign tumors that exhibit schwann cell differentiation and arise from peripheral nn
Antoni A and Antoni B
A- cellular
B- noncellular
schwannoma
Verocary bodies
anuclear rows
schwannoma
Sx from schwannomas
usually from compression
tinnitus, hearing loss
in cranial vault where are schwannomas
cerebellopontine angle where attach to CN VIII
acoustic neuroma
schwannoma in CPA
What is a neurofibroma
benign nerve sheath tumor
heterogenous in composition–neoplastic schwann cells admixed with perineurial like cells, fibroblasts, mast cells and CD34+ spindle cells
cell marker for neurofibroma
CD34+
pedunculated nodule with CD34+
supergicial cutaneous NF
pedunculated nodules all over with CD34+
NF1- associated
large plaquelike elevation of skin CD34+
diffuse NF, assoc NF1
plexiform neurofibromas
deep or superficial locations in association with nerve roots or large nerves and ALWAYS NF1 related
guaranteed to see what with NF-1
plexiform neurofibromas
what are malignant peripheral nerve sheath tumors though to arise from
malignant transformation of plexiform neurofibromas
divergent differentiation
focal areas that have other lines of differentiation
glandular, cartilaginous, osseous, rhabdomyoblastic morphology
triton tumor
Malignant PNST with divergent differentiation
cafe au lait spots
NF 1
NF 2
auto dominant
range of tumors
b/l CN VIII schwannoma and multiple meningiomas
composition of bone matrix
osteoid(35%) and mineral component(65%)
what collagen is in bone
type I
what regulates synthesis of boney matrix
hormonal and local mediators
what indicates inactive osteoblasts
decrease in cytoplasm
what are osteocytes
inactive osteoblasts that become embedded in matrix
osteocytes help what
control Ca and phosphate levels in microenvironment and detect mechanical forces “mechanotransduction”
specialized mutlinucleated macrophages in bone
osteoclasts
how do osteoclasts break down bown
cell surface integrins form seal for resorption pit and then secretion of acid and neutral proteases (mmp) cause dissolution inorganic and organic components of bone
how many nuclei are in osteoclasts
3-25
osteoclast can be mis identified as what
megakaryocyte
zones in active bone growth plate
reserve zone zone of proliferation zone of hypertrophy zone of mineralization primary spongiosa
how much of adult skeleton is replaced anually
10%
peak bone mass
after cessation of skeletal growth
role of OPG
bind up RANKL so osteoclasts cannot be activated
what stimulates production RANKL
M-CSF on osteoblast
what gene is involved when have short broad terminal phalanges on first digits
HOXD13
Bradydactyly types D and E
what gene is involved in achondroplasia
EGR3
short stature
midface deformity
genes in osteogenesis imperfecta types 1-4
COL1A1
COL1A2
bone fragility
what type of collagen is affected in osteogenesis imperfecta
type I
most common disease of growth place
achondroplasia
sclera is blue small teeth
osteogenesis imperfecta
small teeth in OI is from what
decreased dentin and poor enamel from dec in collagen I
what forms of OI are just less Sx than type I
3 and 4
type II OI prognoisis
usually die in utero
so many fractures
marble bone disease
osteopetrosis
what causes OP
reduced bone resoprtion and diffuse skeletal sclerosis from impaired formation and function of osteoclasts
what component of bone in OP is overproduced
mineral
appearance of OP on XR
chalk appearing, so white
bowing of long bones
BM in OP
primary spongiosa fills cavity so no room for blood cells
what aprt of long bone is most affected in OP
metaphysis
lab findings in OP
anemia, thrombocytopenia, leukopenia (infections)
findings in infant with OP
CN defects from small foramina
infections from leukopenia
prominant HSM from dec BM
mutation in OP
CA2 metabolic enzyme
dysostoses
abrnomalities in single bone or localized group of bones
arise from defects in migration and condensation of mesenchyme
dysplasia of bone
global disorganization of bone and cartilage
