Radiation therapy is associated with fewer recurrences in mesenchymal chondrosarcoma

Background: Mesenchymal chondrosarcoma (MSC) is a rare variant of chondrosarcoma. Because of the rarity of the disease, most studies only contain a small number of patients and thus the prognostic variables and role of adjuvant therapies remain controversial. Questions/purposes: We therefore asked (1) what the overall and disease-free survival were for patients with this diagnosis at 5 and 10 years; (2) whether there were significant prognostic factors associated with survival; and (3) whether use of adjuvant chemotherapy or radiotherapy was associated with survival in patients with MSC. Methods: We retrospectively reviewed the cases of MSC diagnosed from 1979 to 2010 at one referral center. Forty-three cases were identified. Thirty-seven cases were analyzed for demographics, treatments, and outcomes. Thirty patients with localized disease were analyzed for prognostic factors. The minimum followup was 1 month (mean, 6 years; range, 1 month to 17 years). There were 17 females and 20 males. The mean age at diagnosis was 33 years (range, 11-65 years). Nineteen cases were skeletal and 18 cases were extraskeletal. Seventy-six percent of the tumors were located in the trunk. Results: Five- and 10-year overall survival was 51% and 37%, respectively. Five- and 10-year disease-free survival was 23% and 5%, respectively. Age (< 30 years) and male sex were associated with poorer overall and disease-free survival in patients presenting with a localized tumor, respectively. Patients who did not receive radiotherapy were more likely to have a local recurrence. Adjuvant chemotherapy failed to show a significant association with overall, disease-free, metastasis-free, or local recurrence-free survival. Conclusions: The present study reinforced the role of adjuvant radiotherapy for local tumor control. Level of Evidence: Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.