|
Year |
2002 |
|---|---|
|
Question Number |
99. |
|
Category |
Orthopaedic Disease |
Question
A 35-year-old patient has left knee pain. The radiographs and CT scans are shown in Figures 19a through 19c. A biopsy specimen is shown is shown in Figure 19d. What is the most likely diagnosis?
1- Giant cell tumor
2- Giant cell rich osteosarcoma
3- Renal cell carinoma
4- Chondroblastoma
5- Hyperparathyroidism(Brown tumor)
Figures
Answer (click for answer)
Answer-1- Giant cell tumor
The xrays show a distal femur with a lesion centered at the old physis extending into the metaphysis and epiphysial regions more or less equally. The lesion has thinned out the cortex and even broken through in one area. There does not appear to be much soft tissue reaction. The location within the bone, the locally aggressive nature, and the lack of soft tissue reaction all make giant cell tumor the number one choice before you even get the pathology slide.
Looking at the pathology, there are giant cells. This does not make the diagnosis! But if you look at the background stromal cells, they have the same bland appearance as the cells in the giant cells. This makes it a giant cell tumor only.
Reference: Miller MD: Review of Orthopaedics ed 3. Philadelphia PA,WB Saunders, 2000, 421-424.