Ewing's Sarcoma Flashcards
What is the epidemiology of Ewing’s Sarcoma ?
It occurs mostly in males b/w the age of 5-30.
what is the common location of Ewing’s Sarcoma ?
In 50% of the time it occurs on the diaphysis of the long bones.
what are the bones that are most commonly affected in Ewing’s Sarcoma ?
femur, tibia, fibula, pelvis and the spine.
what are the X-ray findings in Ewing’s sarcoma ?
Moth eaten appearance as it is a primitive tumor. It also has onion skin and sunburst appearance due to periostial reaction.
What is Codman’s triangle ?
It is a small triangular shaped ectopic bone seen on the X-ray of the Ewing’s Sarcoma which is the result of ectopic bone formation that invades the soft tissue.
What is the histology of Ewing’s Sarcoma ?
Histologically Ewing’s Sarcoma consist of small, round blue cells with prominent nuceli and minimal cytoplasm and the cells may arrange in a pseudorosette fashion.
What is the key genetic mutation in Ewing’s sarcoma ?
It consist of a fushion protein called EWS/FLI-1 due to (11,22) translocation.
What is the clinical presentation of Ewing’s Sarcoma ?
It mimics infection as the patients presents with pain, fever, tenderness and a mass or Swelling.
What are the common blood findings in Ewing’s Sarcoma ?
Elevated ESR and CRP + eleavted WBC.
How to make the definite diagnosis of Ewing’s Sarcoma ?
Bone marrow biopsy to differentiate ES from other small round blue cell bone tumors such as Rhabdomyosarcoma.
What are the immuno-histochemical markers of Ewing’s Sarcoma ?
CD99+, MIC2+, Vimentin+ , and periodic acid schiff +
What is the Tx protocol for Ewing’s Sarcoma
It consist of chemotherpay followed by local control of tumor with wide resection and or radiation therapy.
When is chemotherapy used in Ewing Sarcoma ?
When it is high grade or is spread to other bones and lungs.
