Figure 1

Representative immunohistochemical staining of chondroblastic and giant cell tumors. IHH showed nuclear and cytoplasmic staining, albeit weak, predominantly in giant cell tumors. Nuclear SP7 was expressed in very few tumors, and only a single chondroblastoma. Nuclear SOX9 was most common in the chondromyxoid fibromas, chondroblastomas. RUNX2 was present in the stromal cells of giant cell tumors. CBL, chondroblastoma; CMF, chondromyxoid fibroma; GCT, giant cell tumor; IHH, Indian hedgehog.