Fig. 18.31 Chondrosarcoma. Background cartilaginous matrix material
of a chondrosarcoma. Note the magenta color. This is characteristic of
chondroid lesions (May-Grunwald-Giemsa x MP).
Fig. 18.32 Chondrosarcoma. High-grade chondrosarcoma FNAB. The cells
are very large compared to the background red blood cells. Multinucleation
is present (May-Grunwald-Giemsa x HP).
encapsulated. The translocation t (9; 22) (q22; q12) is well
specimens are cellular with an abundant myxoid background
in which cords of rather bland round to oval cells are found.
The nuclei often have longitudinal grooves and inconspicuous
nucleoli. Lacunae with chondrocytes may sometimes be found
as well (Figs. 18.34- 18.36). The cells are positive for PAS and
S-100 but negative for cytokeratins.
Clear cell chondrosarcoma is rare. It has cells with centrally
placed nuclei and optically clear cytoplasm. Areas of more
obvious chondrosarcomas may also be present.150 (Fig. 18.37).
Key features of mesenchymal chondrosarcoma
• Highly cellular specimens;
• Cartilage mixed with small round blue cells;
• Osteoclast like giant cells;
• Cells are PAS negative;
Fig. 18.33 Chondrosarcoma. Tissue section of high-grade
chondrosarcoma demonstrating crowding of cells and occasional
binucleation (H&E x HP).
Fig. 18.34 Myxoid chondrosarcoma. Myxoid chondrosarcoma showing
magenta background material (May-Grunwald-Giemsa x MP).
• Calcification and ossification; and
• Occasionally necrosis and hemorrhage.
Key features of myxoid chondrosarcoma
• Abundant metachromatic myxoid stroma;
• Uniform round to oval cells;
• Nuclear grooves and intracytoplasmic nuclear invagi-
• PAS positive cells.
Key features of dedifferentiated chondrosarcoma
• Undifferentiated sarcomatoid elements;
• Classic low-grade elements present; and
• Variable cellularity on FNAB.
Key features of clear cell chondrosarcoma
• Centrally placed nuclei;
• Optically clear cytoplasm; and
• Areas of obvious chondrosarcoma.