Sarcoma Flashcards
What are sarcomas?
Tumors that show evidence of mesenchymal differentiation
Most common location for sarcoma?
Extremities. Extremity sarcomas account for nearly 50% of adult sarcomas while retroperitoneal and intra-abdominal sarcomas represent approximately 15%.
Name several genetic syndromes associated with sarcoma development.
Gardner’s syndrome (multiple desmoid tumors), Li-Fraumeni syndrome (soft tissue sarcoma osteosarcoma), Neurofibromatosis I (malignant peripheral nerve sheath tumors)
Name several environmental factors associated with sarcoma development.
Herbicide exposure, pervious radiation exposure (> 3 year delay from exposure), lymphedema (angiosarcoma - Stewart-Treves Syndrome)
What is the primary treatment modality for soft-tissue sarcomas for all locations and the majority of histologic subtypes?
En-block surgical resection
How do extremity sarcomas typically present?
Either a mass in the area or a trivial traumatic event initially draws attention to the area.
What is the first step in management when a mass is discovered?
Biopsy, typically core needle biopsy
What are alternative ways to biopsy?
Open biopsy - excisional if the mass is < 3cm or incisional if > 3cm
Should you include the biopsy tract in the resection?
Yes absolutely
How is the histologic type of sarcoma determined?
Given >50 different types, classification is based on light microscopic appearance, presumed site of origin, and immunohistochemical and molecular markers.
What is the most common soft tissue sarcoma of the extremity?
Liposarcoma and malignant fibrous histiocytoma.
What is the most common soft tissue sarcoma of the extremity in the pediatric population?
Rhabdomyosarcoma and fibrosarcoma
What are the most important predictors of outcome in extremity sarcomas?
Histologic type, grade, and size
What are the most common imaging modalities for evaluation of soft tissue sarcomas?
CT and MRI
What is the most common site of metastasis from extremity soft tissue sarcoma?
Lungs - CT scan of the chest is indicated, particularly for high-grade lesions
How are sarcomas staged?
They are staged based off the standard TNM system, but grade is also included.
List the different categories of the tumor type (T)
Tx (Primary tumor cannot be assessed), T0 (No evidence of primary tumor), T1 (Tumor 5cm in greatest dimension), T2a (Superficial tumor), T2b (Deep tumor)
List the different categories of the regional lymph nodes (N)
Nx (Regional lymph nodes cannot be assessed), N0 (No lymph node metastasis), N1 (Regional lymph node metastasis)
List the different categories of metastasis (M)
M0 (No distant metastasis), M1 (Distant metastasis)
List the different categories of histologic grade (G)
Gx (Grade cannot be assessed), G1 (Grade 1), G2 (Grade 2), G3 (Grade 3)
What typically surrounds a sarcoma?
Pseudocapsule
Should the pseudocapsule be removed?
Absolutely - local recurrence rates decreased dramatically when this was recognized. Radical resection is often performed.
What margins are acceptable for resection?
1-2 cm margins are ideal. (Wide excision alone with 1cm margins is sufficient for low grade sarcomas. When tumors are close to neural or bony structures, close margins are accepted to avoid significant functional impairment.
When should adjuvant radiation therapy be considered?
For recurrent sarcoma or in lesions > 5cm, particularly if margins are < 1 cm
