Soft tissue Flashcards
nonneoplastic mimics of malignancy
fat necrosis
nodular fasciitis
proliferative fasciitis/myositis
ischaemic fasciitis
myositis ossificans
intravascular papillary endothelial hyperplasia
idiopathic retroperitoneal fibrosis (vs sclerosing WDL)
pleomorphic lipoma vs ALT/WDL
PL:
superficial
back and neck of older men
well circumscribed
floret cells
inconspicuous vessels
CDK4, MDM2-
cellular angiolipoma vs Kaposi sarcoma
CAL:
subcutaneous
well circumscribed
small vessel thrombi
mature fat
lipoblastoma (features)
<10yo
lipoblasts in myxoid stroma
PLAG1 rearrangement (cf DDIT3 in myxoid liposarcoma)
neoplastic benign mimics of malignancy
lipoma variants
rhabdomyoma
ancient schwannoma
bizarre neurofibroma
atypical leoimyoma
PHAT
IMT
angiomatoid fibrous histiocytoma
malignant mimics of benign
well differentiated liposarcoma
low grade fibromyxoid sarcoma
epithelioid sarcoma
angiosarcoma in breast
Kaposi sarcoma
nearly normal malignancy
WDL/ALT
Kaposi sarcoma
scalp lesions - think of…
meningioma
angiosarcoma
shoulder/neck - think of…
spindle cell lipoma
nuchal-type fibroma (assoc with Gardner syndrome)
elastofibroma
abdominal wall - think of…
endometriosis
endometrial stromal sarcoma
vulval/vaginal soft tissue tumours
adenocarcinoma (Sister Mary Joseph nodule)
mesothelioma
HPC vessels
solitary fibrous tumour (incl HPC dura/sinonasal)
synovial sarcoma
mesenchymal chondrosarcoma
nasopharyngeal angiofibroma
meningioma
MPNST
thymoma
infantile fibrosarcoma
myofibromatosis
endometrial stromal sarcoma
myxoid tumours - adipocytic
benign: spindle cell lipoma
malignant: myxoid liposarcoma (lipoblasts, crow’s feet vessels, DDIT3 rearr.)
myxoid tumours - fibroblastic
benign: myofibroma (usu <2yo, myofibroblasts, HPC vessels, fibromyxoid stroma)
malignant:
low grade fibromyxoid sarcoma (young, pelvis, whorled spindle cells +/- giant rosettes, FUS rearr.)
myxofibrosarcoma (older, subcut, curvilinear vessels, pleomorphic)
myxoinflammatory fibroblastic sarcoma (hands and feet, R-S like cells)
myxoid tumours - unknown differentiation
benign: myxomas
intermediate:
ossifying fibromyxoid tumour (older males, limbs, subcut, cords of round cells, shell of lamellar bone, phf1 gene rearr.)
mixed tumour (CK+ cf myxoid chrondrosarc, s100+ cf metastatic ca)
malignant: extraskeletal myxoid chrondrosarcoma (lobular, cellular at periphery, EWS rearr.)
myxomas
intramuscular myxoma (esp thigh/pelvis, cellular but no vessels cf MLS/MFS)
juxtaarticular myxoma (esp knee)
digital fibromyxoma
superficial angiomyxoma (head/neck/trunk/genital, thin walled vessel, epithelial component eg cyst, assoc. Carney complex)
deep aggressive angiomyxoma (vulva/pelvis, infiltrative, thick vessels, myoid bundles around vessels)
nerve sheath myxoma vs neurothekeoma
NSM (prev. ‘myxoid’ or ‘classical’ neurothekeoma): rare, extemities esp fingers/knee, myxoid nodules with fibrous border, s100 stong+
Neurothekeoma (prev. ‘cellular neurothekeoma’): young adults, upper body, solid or whorled nests in hyaline collagen, +/- myxoid areas, s100-
sclerotic tumours
sclerosing epithelioid fibrosarcoma
epithelioid haemangioendothelioma
storiform pattern
DF
DFSP
nodular fasciitis
UPS
herringbone pattern
synovial sarcoma
MPNST
fibrosarcoma (eg transformation of DFSP)
leiomyosarcoma
melanoma
spindle cell rhabdomyosarcoma
rhabdoid tumours
proliferative fasciitis/myositis
LMS
RMS
epithelioid sarcoma, proximal type
MPNST (Triton tumour)
melanoma
epithelioid tumours
‘CAMELS CAMP’
carcinoma
angiosarcoma
melanoma
epithelioid sarcoma
leiomyosarcoma
synovial sarcoma
clear cell sarcoma of soft parts
alveolar soft part sarcoma
MPNST
PEComa
small round blue cell tumours - adult
lymphoma
small cell carcinoma
desmoplastic small round cell tumour (CK, WT1, desmin+, EWS-WT1 fusion)
Merkel cell carcinoma
mesenchymal chondrosarcoma (10-40, axial skeleton, chondroid diff, HPC vessels)
small cell osteosarcoma (esp knee)
round cell liposarcoma
synovial sarcoma
small round blue cell tumours - children
lymphoblastic lymphoma
alveolar RMS, solid subtype (CK, WT1, desmin+, PAX3 and PAX7 rearr.)
Wilms tumour (CK, WT1, desmin+, WT1 del or mutation)
medulloblastoma
Ewing sarcoma (membranous cd99, EWS rearr.)
neuroblastoma
retinoblastoma
small cell osteosarcoma
hepatoblastoma
biphasic tumour
usually:
synovial sarcoma
carcinosarcoma
mesothelioma
Wilms tumour
sometimes:
MPNST, germ cell tumour, mixed GIST, thymoma, myoepithelioma
vacuolated cytoplasm
liposarcoma
vascular tumours
smooth muscle
RMS
myxofibrosarcoma
chordoma
nested/alveolar tumours
nested: phaeochromocytoma, paraganglioma, RCC, TCC, granular cell tumour, melanoma, PEComa
alveolar: alveolar soft part sarcoma, alveolar RMS, alveolar lobular breast ca
high grade spindled tumours
dediff liposarcoma
pleomorphic liposarcoma
leiomyosarcoma
pleomorphic RMS
MPNST
angiosarcoma
myxofibrosarcoma
UPS
carcinoma, melanoma, mesothelioma
LG fibromyxoid sarcoma vs myxofibrosarcoma
MFS:
more atypia
infiltrative
purely myxoid
no rosettes
LGFMS:
may have rosettes
t(7;16) (FUS)
malignancy in soft tissue leiomyoma
limbs: >1 mitosis/50HPF
retroperitoneum in women: >10/50HPF
(cf uterus: complex tables based on cell type, atypia, necrosis and mitoses)
