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[Chondrosarcoma of bone in young patients].

Chondrosarcoma is the second most frequent primary malignant bone tumor. It is typically described in adults between 40 and 70 years of age, being the majority of the series published in this age group. The objective of this study was to report a series of young adults (16-40 years old) with a diagnosis of chondrosarcoma of bone in order to describe the particularities of this tumor in this population. From a total of 37 patients between 16 and 40 years old, surgically treated for chondrosarcoma in our institution, 18 had low-grade tumors (G1/atypical cartilaginous tumor), 16 had an intermediate-grade (G2), and a minority had high-grade tumors (2 with a G3 and 1 with a dedifferentiated chondrosarcoma). The overall survival rate was 97% (95% CI 82%-99%) at 2 years of follow-up and 90.5% (95% CI 73-96) at 5 years of follow-up. The local recurrence free rate was 92% (95% CI % 77%-97.5%) at 1 year of follow-up and 89% at 2 and 5 years of follow-up (95% CI 73%-96%). Histological grade was the most relevant prognostic factor. The concordance of the histological grade between the preoperative diagnosis of the biopsy and the surgical resection material was 81% (30/37).