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Find the false statement/s
a. A central chondroid tumor with pain or increased growth should be regarded as chondrosarcoma until proven otherwise by biopsy or benign clinical progress
b. Chondrosarcoma is suggested if the level of scintigraphic activity in the lesion is greater than that in the anterior iliac crest
c. Calcification occurs in 29% of chondrosarcomas on CT
d. Deep endosteal cortical scalloping (greater than 2/3rds) is suggestive of chondrosarcoma as opposed to chondroma -
Radiographic features of Chondrosarcoma are all except
a. 75% of cases show calcification
b. Small low grade chondrosarcoma may not be differentiated from a chondroma, appearing as a well defined lytic lesion with chondroid matrix mineralization.
c. Plain radiography may not accurately define medullary involvement
d. Periosteal reaction is a rare feature of chondrosarcomas -
MRI features of chondrosarcoma are
a. Lesion is slightly hypointense to muscle on T1 and may show focal areas of hyperintensity due to trapped areas of marrow
b. Malignant cartilage shows characteristic increased signal intensity on T2 images and a multilobulated appearance
c. Matrix mineralization manifests as focal areas of signal void
d. Most chondrosarcomas are very well vascularized and enhancement after IV contrast is excellent
e. T2 images have proven valuable in the identification of dedifferentiation, in which case a region of intermediate signal intensity adjacent to the typical hyperintense chondral tumor mass is seen -
Which of the following are true regarding a Secondary Peripheral Chondrosarcoma developing from an Osteochondroma
a. Most Osteochondromas have cartilage caps no thicker than 5mm and a cap in excess of 20mm is likely to be malignant
b. Radiological features of malignant change consist of destruction of part of the calcified cap or ossified stem of the osteochondroma
c. Malignant change should be suspected clinically if pain develops or continued growth occurs after skeletal maturity
d. Radiographs are usually used to measure the thickness of the cartilage cap of the osteochondroma -
True statement/s about Periosteal Chondrosarcoma (a rare form of chondrosarcoma)
a. Typically involves long bones
b. Most commonly involves distal femoral and proximal humeral metaphyses
c. More common in men with a wide range of presentation
d. Radiologically a calcified juxtacortical mass is seen, with cortical thickening and periosteal reaction
e. Involvement of medulla is rare
f. Prognosis is poor.