Soft tissue tumor 李醫師
GIST Gastrointestinal stromal tumor
Stomach
common
Vacuole
nucleus
Cajal
cell : c-kit RTK mutation-> cytoplasm也有
Exon 9, 11 most common
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Polygonal
epithelial-like GIST
PDGFRA RTK mutation
Exon 12, 18
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HPF>20 mitosis
Size
Location:
stomach prognosis good
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2nd
resistance on c-kit
1st
resistance on c-kit exon
13, 17
GIST的基因突變:
大約80%的GIST會有酪氨酸激酶受體KIT的致癌基因突變,目前已發現GIST的KIT有 5個不同外顯子(exon)的基因突變-exon 11 (67%), exon 9 (10%), and exons 8, 13, and 17 (3%),而不同部位的GIST常表現不同KIT基因突變的變異,如:exon 8 (小腸)、exon 9 (小腸、大腸)、而exon 11, 13, 17 (所有部位);另外約5~7%的GIST會有PDGFRA的基因突變在exon 12, 14和18的位置,通常發生在胃的GIST;然而,有10~15%的GIST臨床上無法測得KIT或PDGFRA的基因突變。
在Imitinib治療後exon
9突變的病人約2成會發展出2次的基因突變;而一開始為exon 11突變的病人則超過7成會產生2次的基因突變,而對Imitinib產生抗藥性。
Sunitinib (Sutent):為多靶標的酪氨酸激酶受體抑制劑(含:抑制PDGF和VEGF受體) ,其對exon 13或14突變的GIST具有療效,
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Melanoma, amelanotic type
Pagetoid
spreading
c-kit +
S-100 +
EC junction,
anorectal junction
Very rare
B-RAF
NF1
NRAS
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Sclerotic
type well-differentiated liposarcoma
Spindle cell
neoplasm
Omentum
Perigastric
dedifferentiated
liposarcoma 可能並存
12q amplification
MDM2
CDK4
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Sarcomas
of uncertain differentiation
Synovial sarcoma
Synovial sarcoma
Agrassive
t(X;18) SS18-SSX1 or SS18-SSX2 or SS18-SSX4
Biphasic
pattern: spindle + gland
可以只有spindle
Ddx: GIST,
MPNST
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Inflammatory pseudotumor; IPT
inflammatory myofibroblastic tumor; IMFT
borderline
multinucleated
foreign body Giant cell
Lymphoplasma
cells
Spindle
cells (空亮的核, 明顯核仁)
Ganglion-like
cells (myofibroblast)
Epithelial
type: more aggressive
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ALK1
RTK, dimer
Over-expression,
不用ligand
常見於ATLL; Adult T-cell leukemia/lymphoma, neuroblastoma
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myxoid liposarcoma (MLS), the t(12;22)(q13;p12)
Q13 CHOP
Q12 EWS
Alveolar rhabdomyosarcoma
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