Grade 2 chondrosarcoma: stage I or stage II tumor?

We analyzed chondrosarcomas of bone to assess whether Grade 2 tumors are more appropriately grouped with Grade 1 chondrosarcomas or Grade 3 and dedifferentiated chondrosarcomas (Musculoskeletal Tumor Society Stage I or Stage II). A retrospective chart review identified 109 patients who presented with nonmetastatic chondrosarcoma. Data were gathered on each tumor's histologic grade, extent (intracompartmental versus extracompartmental), resection margin status, and site (axial versus appendicular). The cohort included 60 males and 49 females with a mean age of 50 years. Forty tumors were located in the axial skeleton and the remainder were distributed throughout the appendicular skeleton. Fifty-three tumors were Grade 1, 40 tumors were Grade 2, eight tumors were Grade 3, and eight tumors were dedifferentiated. Statistical analysis established grade as the only significant variable for this group of patients; extracompartmental tumor spread also correlated with outcome, but not independent of the grade. Margin status and site were not statistically significant with respect to outcome. Chi-square analysis also established that Grade 2 tumors are grouped more appropriately with the Grade 1 chondrosarcomas as Musculoskeletal Tumor Society Stage I neoplasms. These data should be considered when developing the surgical plan, particularly for patients with Grade 2 appendicular chondrosarcomas.