Soft tissue/bone sarcoma Flashcards
A 42-year-old female was incidentally found to have an infiltrative contrast enhancing asymptomatic 6 cm mass in the right rectus abdominus muscle. Biopsy reveals desmoid fibromatosis. What treatment should be initially recommended?
A) Active surveillance
B) Definitive radiation
C) Sorafenib
D) Surgical resection
A) Active surveillance
Desmoid tumor behavior varies. Some progress and cause morbidity while others remain indolent or spontaneously regress. Active surveillance is recommended for asymptomatic, stable tumors. Progressing or symptomatic tumors can be treated with systemic therapy, definitive RT or surgery.
What is the preferred timing and dose of RT when used in the treatment of retroperitoneal sarcoma?
A) Preoperative, 50 Gy
B) Preoperative, 60 Gy
C) Postoperative, 50 Gy
D) Postoperative, 60 Gy
A) Preoperative, 50 Gy
Consensus guidelines when RT is incorporated into management of retroperitoneal sarcoma is 50-50.4 Gy preoperatively. Postop has high risk of complications. EORTC STRASS trial of preop RT + surgery versus surgery alone did not show 3-year abdominal recurrence-free survival benefit for RT. Post hoc analysis showed liposarcoma and low-grade RPS may benefit.
What postoperative RT dose is recommended for a high grade malignant peripheral nerve sheath tumor of the upper extremity following R1 resection?
A) 50 Gy
B) 60 Gy
C) 66 Gy
D) 72 Gy
C) 66 Gy
Inferior local control for soft tissue sarcoma resected with positive microscopic margins. It is worthwhile to ask for re-excision if negative margins are possible. A higher dose >/= 70 Gy for gross residual disease
What is the recommended preoperative GTV to CTV expansion for an 8.5 cm high grade myxofibrosarcoma of the vastus lateralis muscle?
A) 3 cm longitudinally and 1.5 cm radially including bone
B) 3 cm circumferentially including peritumoral edema
C) 4 cm longitudinally and 1.5 cm radially, anatomically constrained
D) 5 cm longitudinally and 2.5 cm radially excluding subcutaneous tissue.
C) 4 cm longitudinally and 1.5 cm radially, anatomically constrained
CTV = GTV + 3-4 cm longitudinally and 1.4 cm radially, anatomically constrained, with inclusion of peritumoral edema when feasible.
What is the MOST likely diagnosis of midline mass arising from the sacrum and coccyx that is brachyury positive on biopsy?
A) Chondrosarcoma
B) Chordoma
C) Ewing sarcoma
D) Giant cell tumor of bone
B) Chordoma
Chordomas are rare tumors arising from notochord remnants, most commonly occurring in the skull base and sacrum. Expression of brachyury confirms that diagnosis. Treated with surgical resection and radiation. Hight rates of local recurrence that result in significant morbidity.
