Figure 1

Radiologic and histologic examination of original tumors. A: L835 conventional radiography demonstrates a mildly expansile mixed lytic and sclerotic lesion in the distal radius with spiculated borders (arrow) and an irregular periosteal reaction. Note the presence of an enchondroma in the first metatarsal bone (asterisk). B: L2975 conventional radiography shows an ill-defined expansile mixed lytic and sclerotic lesion (arrow) originating from the distal femur diaphysis with endosteal scalloping of the anterior cortex (asterisk). The sclerotic areas within the lesion suggest osteoid matrix formation. B’: L2975 gross specimen shows intramedullar localization of dedifferentiated chondrosarcoma with chondrocytic and lobulated dedifferentiated compartments. C: L3252 conventional chest radiography shows a large lobulated mass originating from the left chest wall with extensive rib destruction. Subtle chondroid mineralization can be observed in the lesion. Radiological features are suggestive for a chondrosarcoma with a higher grade of malignancy. D: Axial CT image demonstrates chondroid mineralization (arrow) within the intra-abdominal component consistent with the diagnosis of chondrosarcoma. E: H&E staining of high grade L835 original tumor. H&E staining of L2975 original tumor shows anaplastic and cartilaginous component (F) and metastasis of the anaplastic component (G). H&E staining of L3252 original tumor shows anaplastic and cartilaginous component (H) and recurrence of the cartilaginous component (I). J-N: absence of p16 staining is observed in L835 original tumor, L2975 original tumor and metastasis, and L3252 original tumor and recurrence, respectively.