Free Test MCQs/SBAs Oncology & Pathology

Best answer : C .
The radiographic appearance of the lesion emanating from the posterior cortex of the left distal femur is consistent with a surface bone-producing lesion; therefore, the most likely diagnosis is a parosteal osteosarcoma. In an osteochondroma, the cortex and medullary cavity of the lesion are in continuity with that of the native bone. A dedifferentiated chondrosarcoma has histologic components of a highgrade sarcoma plus a benign or low-grade malignant cartilage tumor. Tumoral calcinosis is characterized by amorphous calcium in the soft tissues and does not emanate from the bone itself. While often confused with parosteal osteosarcoma, myositis ossificans is usually more mature at the periphery of the lesion rather than the center. In addition, myositis ossificans does not involve the underlying cortex but remains separate from the bone.

Best Answer: A
Melorheostosis is a rare disorder characterized by the classic radiographic appearance of flowing hyperostosis in a long bone. The hyperostosis may be on the periosteal or endosteal surface of the bone and frequently gives the appearance of wax falling down the side of a candle. The radiographs are diagnostic; therefore, no further work-up is indicated

Best Answer D.
a lucent lesion of the proximal tibial diaphysis, which is expanding the anterior cortex, leading to procurvatum deformity. This lesion is characteristic of osteofibrous dysplasia.

Best answer : D .
The radiograph shows a destructive lesion of the distal femur. As this is likely a malignancy (osteosarcoma) it should be staged prior to biopsy .

Correct Answer : E .https://orthopaedicacademy.net/wp-admin/post.php?post=11056&action=edit The radiographs show a radiolucent lesion in the proximal femur. In a patient older than age 40 years, a new painful bone lesion most likely represents metastatic carcinoma or multiple myeloma even if the patient does not have a known history of cancer. The diagnosis must be firmly established and the patient should be staged prior to initiating treatment. Imaging studies should be completed prior to proceeding with a biopsy. This patient should undergo a bone scan to look for other lesions. A CT scan of the chest, abdomen, and pelvis should be performed to look for a primary tumour as well as other sites of metastases. (Lung or kidney would be the most common primary sites for a patient who presents with metastases of unknown origin.) Serum and urine protein electrophoresis should be obtained to look for multiple myeloma.

Best answer: E . The radiological features and clinical scenario are suggestive of a Non-ossifying fibroma (NOF). NOFs are the most common type of non-neoplastic fibrous bone lesion and are a larger version ( >3cm) of a fibrous cortical defect; both are encompassed by the term fibroxanthoma or metaphyseal fibrous defect. NOFs are very common in children and adolescents, and the most common fibrous, bony lesion in this age group 6, with a peak incidence at 10-15 years of age. They are usually not seen beyond the age of 30, as they spontaneously heal, being gradually filled in by bone. The majority of NOFs are asymptomatic. Larger lesions may be painful and potentially weaken the bone enough to predispose to pathological fracture. NOFs are typically a multiloculated lucent lesion with a sclerotic rim. They are located eccentrically in the metaphysis, adjacent to the physis. As the patient ages, they seem to migrate away from the physis. They have no associated periosteal reaction, cortical breach or associated soft tissue mass.

Best Answer: B .
Synovial osteochondromatosis is a rare condition typically affecting middle-aged men. The computed tomogram demonstrates the osteocartilaginous nodules. Early in the disease, arthroscopic removal of loose bodies and synovectomy usually results in an acceptable outcome. In cases of progressive disease resulting in secondary shoulder arthrosis, shoulder arthroplasty may be required.