(ANSWERS AT THE BOTTOM OF THE PAGE)
1. True about Chondrosarcoma are
a. It is a malignant tumor
b. It is a bone forming tumor
c. 25% of all biopsied malignant bone tumors are chondrosarcomas
d. Synovial chondromatosis can turn into a chondrosarcoma
e. 8-17% of all biopsied primary bone tumors are chondrosarcomas
2. Which of the folllowing can progress to become a chondrosarcoma
a. Enchondroma
b. Osteochondroma
c. Chondromyxoid fibroma
d. Chondroblastoma
e. Synovial chondromatosis
3. Myxoid chondrosarcoma belongs to which grade of chondrosarcoma
a. Grade 1
b. Grade 2
c. Grade 3
d. None
4. Find the true statement/s
a. Chondrosarcoma is common in children
b. 50% of patients are more than 40 years old with a mean peak incidence of 50 years
c. Male to female ratio is 1.5:1
d. Clinical presentation is usually pain of insidious onset
e. Chondrosarcoma can also present with palpable mass(28%) or pathological fracture(27%)
5. Which of the following is the least commonly affected site for chondrosarcoma?
a. Pelvis
b. Proximal Femur
c. Proximal Humerus
d. Hands and Feet
6. 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
7. 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
8. 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
9. 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
10. 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.
11. True statement/s about Mesenchymal Chondrosarcoma (another rare type of chondrosarcoma)
a. Occurs at a younger age (third and fourth decade)
b. Much more cellular malignant matrix than a normal chondrosarcoma
c. Some predilection for ribs and mandible noted
d. Indistinguishable from a central chondrosarcoma and often shows characteristic chondroid calcification
e. Local recurrence and disseminated metastases occur late and less frequently than with conventional chondrosarcoma
12. True statement about Clear-cell Chondrosarcoma (another rare type of Chondrosarcoma)
a. 2% of all chondrosarcomas
b. It is a high grade type of Chondrosarcoma
c. Patient has a long history and a better prognosis
d. Radiographically resembles Chondroblastoma and Chondromyxoid fibroma
e. Involves the ends of long bones, especially the proximal ends of femur or humerus after closure of the growth plate
f. Lesion is usually lytic and may present a loculated or soap-bubble appearance
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ANSWERS:
1. a,c,d and e are true statements. b is false because chondrosarcomas are cartilage forming tumors and not bone forming tumors. Examples of bone forming tumors are the benign osteoma, osteoid osteoma, osteoblastoma and the malignant osteosarcoma.
2. All of them can progress to a chondrosarcoma.
3. b. Grade 2. Based on the histological grade, chondrosarcomas are classified into low grade (grade 1 - 45-50% of cases), Myxoid (grade 2 - 30-43% of cases) and high grade (grade 3 - 8-25% of cases). It is important to remember that there is an entity called dedifferentiated chondrosarcoma where along side chondrosarcoma another malignant high grade non-chondroid neoplasm is present (it evolves from chondrosarcoma) like Osteosarcoma or Malignant Fibrous Histiocytoma.
4. b,c,d and e are true. a is the false statement because chondrosarcoma is rare in children.
5. d. Hands and feet. Only 1-4% of all chondrosarcomas develop in the Hands and feet.
6. c is the false statement. 92% of chondrosarcomas show calcifications on CT and 75% of chondrosarcomas show calcifications on Radiography.
7. d is the wrong statement. 50% of chondrosarcomas show periosteal reaction.
8. d is very wrong. Most of the chondrosarcomas are poorly vascularized and show very minimal contrast enhancement typically a peripheral or septal pattern.
9. d is a wrong statement. Cartilage caps are not visible on radiographs.
10. f is the only wrong statement. After resection of the tumor, this type of chondrosarcoma has good prognosis.
11. e is the only wrong statement. Mesenchymal Chondrosarcoma which almost radiologically appears similar to the typical central chondrosarcoma has a cellular matrix which is more malignant than the typical central chondrosarcoma and so the metastases happen more early and more commonly when compared to the typical variety.
12. b is the only wrong statement. The clear cell chondrosarcoma is a low grade tumor and that is the reason for the long history and better prognosis.
1. True about Chondrosarcoma are
a. It is a malignant tumor
b. It is a bone forming tumor
c. 25% of all biopsied malignant bone tumors are chondrosarcomas
d. Synovial chondromatosis can turn into a chondrosarcoma
e. 8-17% of all biopsied primary bone tumors are chondrosarcomas
2. Which of the folllowing can progress to become a chondrosarcoma
a. Enchondroma
b. Osteochondroma
c. Chondromyxoid fibroma
d. Chondroblastoma
e. Synovial chondromatosis
3. Myxoid chondrosarcoma belongs to which grade of chondrosarcoma
a. Grade 1
b. Grade 2
c. Grade 3
d. None
4. Find the true statement/s
a. Chondrosarcoma is common in children
b. 50% of patients are more than 40 years old with a mean peak incidence of 50 years
c. Male to female ratio is 1.5:1
d. Clinical presentation is usually pain of insidious onset
e. Chondrosarcoma can also present with palpable mass(28%) or pathological fracture(27%)
5. Which of the following is the least commonly affected site for chondrosarcoma?
a. Pelvis
b. Proximal Femur
c. Proximal Humerus
d. Hands and Feet
6. 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
7. 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
8. 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
9. 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
10. 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.
11. True statement/s about Mesenchymal Chondrosarcoma (another rare type of chondrosarcoma)
a. Occurs at a younger age (third and fourth decade)
b. Much more cellular malignant matrix than a normal chondrosarcoma
c. Some predilection for ribs and mandible noted
d. Indistinguishable from a central chondrosarcoma and often shows characteristic chondroid calcification
e. Local recurrence and disseminated metastases occur late and less frequently than with conventional chondrosarcoma
12. True statement about Clear-cell Chondrosarcoma (another rare type of Chondrosarcoma)
a. 2% of all chondrosarcomas
b. It is a high grade type of Chondrosarcoma
c. Patient has a long history and a better prognosis
d. Radiographically resembles Chondroblastoma and Chondromyxoid fibroma
e. Involves the ends of long bones, especially the proximal ends of femur or humerus after closure of the growth plate
f. Lesion is usually lytic and may present a loculated or soap-bubble appearance
---------------
ANSWERS:
1. a,c,d and e are true statements. b is false because chondrosarcomas are cartilage forming tumors and not bone forming tumors. Examples of bone forming tumors are the benign osteoma, osteoid osteoma, osteoblastoma and the malignant osteosarcoma.
2. All of them can progress to a chondrosarcoma.
3. b. Grade 2. Based on the histological grade, chondrosarcomas are classified into low grade (grade 1 - 45-50% of cases), Myxoid (grade 2 - 30-43% of cases) and high grade (grade 3 - 8-25% of cases). It is important to remember that there is an entity called dedifferentiated chondrosarcoma where along side chondrosarcoma another malignant high grade non-chondroid neoplasm is present (it evolves from chondrosarcoma) like Osteosarcoma or Malignant Fibrous Histiocytoma.
4. b,c,d and e are true. a is the false statement because chondrosarcoma is rare in children.
5. d. Hands and feet. Only 1-4% of all chondrosarcomas develop in the Hands and feet.
6. c is the false statement. 92% of chondrosarcomas show calcifications on CT and 75% of chondrosarcomas show calcifications on Radiography.
7. d is the wrong statement. 50% of chondrosarcomas show periosteal reaction.
8. d is very wrong. Most of the chondrosarcomas are poorly vascularized and show very minimal contrast enhancement typically a peripheral or septal pattern.
9. d is a wrong statement. Cartilage caps are not visible on radiographs.
10. f is the only wrong statement. After resection of the tumor, this type of chondrosarcoma has good prognosis.
11. e is the only wrong statement. Mesenchymal Chondrosarcoma which almost radiologically appears similar to the typical central chondrosarcoma has a cellular matrix which is more malignant than the typical central chondrosarcoma and so the metastases happen more early and more commonly when compared to the typical variety.
12. b is the only wrong statement. The clear cell chondrosarcoma is a low grade tumor and that is the reason for the long history and better prognosis.
