Quiz Case #4

Clinical Presentation:
A 16-year-old male was seen in consultation for a painful lesion of the proximal humerus.
Radiological Findings:
  • Plain film showing a destructive lesion in the proximal humeral metaphysis.
Pathological Findings: :
  • Biopsy specimen, low magnification
  • High magnification


Q1. What is your diagnosis?
1 Osteosarcoma, high grade
2 Osteosarcoma, well-differentiated (low-grade)
3 Aggressive osteoblastoma
Q2. What is the distinguishing and diagnostic feature of this tumor?
1 Highly pleomorphic mesenchymal cells
2 Tumor osteoid
3 Characteristic immunophenotype
4 Characteristic chromosomal abnormality
Q3. Prognosis depends on
1 Tumor response to pre-operative chemotherapy
2 Surgical stage
3 Skeletal site of involvement
4 All of the above
This is a self-assessment test. The results are neither collected nor stored.