Sarcoma Flashcards
How common are adult sarcomas (percentage of malignancies)
1%
15% of childhood malignancies
What are the most common sarcomas in young adults
Synovial, Ewing, alveolar rhabdomyosarcoma
What are the most common sarcomas in older adults
Liposarcoma, leiomyosarcoma, undifferentiated pleomorphic sarcoma, fibrosarcoma
What is the median age for adult sarcomas
50-60
What sarcomas are associated with NF1?
Malignant peripheral nerve sheath tumours
Rhamdomyosarcoma
What sarcomas are associated with Li-Fraumeni syndrome?
Rhabdomyosarcoma
Which sarcomas are most commonly associated with previous radiation therapy
Angiosarcoma, undifferentiated pleomorphic, fibrosarcoma
What general type of tissue do sarcomas arise from
Mesenchymal
How is T stage defined for extremity soft tissue sarcomas
T1 = 5.0
T2 5.1-10.0
T3 10.1-15
T4 15.1+
N1= any node involvement
How is soft tissue extremity sarcoma staged
I: Tany N0M0 grade 1
II: T1 grade 2-3
III: T2-4 grade 2-3
IV: any N or M involvement
What are some examples of less aggressive and aggressive fibromatosis
Dupuytrens (benign)
Desmond tumours: frequently recur, but do not metastasize.
Which type of sarcoma arises from adipose tissue, what are the main subtypes
Liposarcoma
-well differentiated (amplification of region of chromosome 12q encoding MDM2 and CDK4)
-myxoid (t12;16 translocation)
-pleomorphic (complex karyotype/genetic instability)
What type of sarcoma is associated with skeletal muscle. What are the most common subtypes
Rhabdomyosarcoma
-note they arise in areas without skeletal muscle as they arise from stem cells rather than differentiated myocytes
-Alveolar (most common in childhood, specific common translocation pax:FOX01)
-embryonal (childhood); includes spindle cell/sclerosing. Negative for pax:fox01
-pleomorphic/undifferentiated
What type of sarcoma is associated with smooth muscle and where are they most commonly found
Leiomyosarcoma
Found in extremities and retroperitoneum.
What type of sarcoma is associated with cartilage
Chondrosarcoma
What type of sarcoma is associated with blood vessels. What is the benign condition
Angiosarcoma
Benign:haemangioma
What are the microscopic features of undifferentiated pleomorphic sarcoma
Pleomorphic, bizarre cells
MANFICS
Mitosis
Atypia
Necrosis
Foamy cytoplasm
Inflamed collagenous cytoplasm
Which sarcomas are more likely to metastasis to lymph nodes
CARE
Clear cell sarcoma
Angiosarcoma
Rhabdomyosarcoma
Epithelioid sarcoma
What is the most radiosensitive type of adult soft tissue sarcoma
Myxoid liposarcoma
What IHC markers are general for all muscle types
Desmin
MSA (muscle specific actin)
What is one IHC specific to smooth muscle, and one specific to skeletal muscle
SMA (smooth muscle actin): smooth muscle
MyoD: skeletal/striated muscle. This is a nuclear marker
What are the microscopic features of myxoid liposarcoma
Uniform round to oval shaped primitive non-lipogenic cells
Chicken wire vasculature
Abundant myxoid matrix
Multivacuolar and univacuolar lipoblasts (sometimes with appearance of small signet ring cells)
What are key genetic/molecular abnormalities associated with well differentiated liposarcoma
12q amplification, which results in amplification of CDK4 (cell cycle progression) and MDM2 (p53 breakdown)
FISH for MDM2 amplification
p16 positivity is a highly sensitive, but non-specific surrogate for CDK4 amplification (due to negative feedback loop)
What sarcomas are most associated with distant metastasis
Leiomyosarcoma
Dedifferentiated liposarcoma and myxoid liposarcoma
