Prognostic factors in chondrosarcoma. A comparative study of cellular DNA content and clinicopathologic features

In a retrospective study of 45 surgically treated chondrosarcomas, the prognostic significance of the cellular DNA content and different clinicopathologic factors was analyzed both separately and in combination. The relationship between these parameters was also investigated. Diploid (normal DNA content) chondrosarcomas were associated with a significantly (P ≤ 0.001) higher ten-year survival rate than hyperploid (abnormally increased DNA content) chondrosarcomas. Apart from ploidy, factors such as tumor size, tumor location and tumor grade also proved to be of prognostic importance. However, patients with diploid tumors had a better prognosis than those with hyperploid tumors, almost regardless of location, size, grade or even treatment. Nevertheless, additional prognostic information could be obtained by combining ploidy with size, location and grade of the tumors. Ploidy and treatment were significantly related to the ten-year recurrence rate. No statistical relationship could be demonstrated between ploidy and other prognostic factors. A strong correlation (P ≤ 0.001) was, however, found between location and size of the tumors. Thus, distal tumors were significantly smaller and, moreover associated with a better prognosis than axial tumors. The results indicate that ploidy probably is the best predictor of the clinical course in chondrosarcoma. While tumor location and size may be assumed to determine the conditions for radical surgery, ploidy and grade seem to reflect the inherent biological malignancy in chondrosarcoma. Consideration of all these factors seems to provide not only valuable prognostic information, but also guidelines for treatment.