Question
A 35-year-old man has experienced pain in the area of the left knee for more than 1 month. On physical examination, there is tenderness to palpation of the distal left thigh and knee. The area is firm, but there is no erythema or warmth. A radiograph of the left leg shows a 7-cm mass in the distal femoral epiphyseal area, with a “soap bubble” appearance. Microscopic examination of a biopsy specimen of the lesion shows multinucleated cells in a stroma predominantly composed of spindle-shaped mononuclear cells. What is the most likely diagnosis?
A. |
Ewing sarcoma |
B. | Osteoblastoma |
C. |
Osteitis fibrosa cystica |
D. |
Giant-cell tumor |
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