Grading in Myxofibrosarcoma of the Extremities Can Predict Survival and Local Control

The aim of this retrospective analysis is to understand the natural history of myxofibrosarcoma (MFS), in particular whether the prognosis can be influenced by histologic grade.

We reviewed 229 adult patients with primary MFS of the limbs. We analyzed disease-specific survival (overall survival [OS]) and local recurrence (LR).

Median age was 70 years (range, 19-92). Sixteen (7.0%) were grade 1, 38 (16.6%) grade 2, and 175 (76.4%) grade 3. A worse OS was found in grade 3 MFS (73.1%) than in grade 2 and 1 MFS (91.9 and 100%, respectively) at 5 years (p = 0.031). Locally recurred MFS had a worse OS (p = 0.018). A better LR-free rate (100% at 5 years) was observed in grade 1 MFS; however, a similar rate was observed between grade 2 and 3 tumors (77.1 and 80.0% at 5 years, respectively, p = 0.412).

Grade 3 MFS has the worst prognosis. Grade 1 MFS have the lowest risk of LR. These data could help identify a high-risk patient group, thus selecting a more careful follow-up for higher-risk patients. Since MFS mostly affects the elderly population, it might be useful to reserve adjuvant treatments (radiotherapy and chemotherapy) to higher-risk patients.