Radiotherapy associated with improved survival for high-grade sarcoma of the extremity.

Background: The impact of radiotherapy on local control in limb-preserving surgery for high-risk sarcoma has been well studied. However, the impact of the use and timing of radiation therapy on survival is unclear.

Methods: From 1988 to 2010, patients with Stage III extremity sarcoma were identified within the SEER registry and cohorts were created using propensity score matching between irradiated and non-irradiated groups.

Results: A total of 2,606 patients were identified, with a median age of 59 years a majority were white (81%), male (54%), received radiotherapy (78%), and had lower extremity (80%) sarcomas. The most common subtype was fibrohistiocytic (29.8%). Patients treated with radiotherapy were younger (57.2 vs. 60.3 years) and differed in subtype compared to those untreated. The matched cohorts were better balanced for all factors. Radiation therapy was associated with a 5% 5-year survival advantage on univariate analysis for both the unmatched (P = 0.002) and matched cohorts (P = 0.01). On multivariate analysis radiotherapy was associated with a 20% and 30% survival advantage for the matched and unmatched cohorts, respectively (P ≤ 0.02). The timing of radiotherapy did not affect survival.

Conclusions: Radiotherapy, regardless of the timing, is associated with improved survival in high-risk sarcoma.