Adjuvant radiation for stage II-B soft tissue sarcoma of the extremity

Adjuvant radiation therapy (RT) has been shown to improve local control in patients with high-grade soft tissue sarcoma (STS) of the extremity. This study sought to define the optimal management in patients with stage II-B (high-grade, size < or = 5 cm) tumors.

Between July 1982 and December 1998, 204 adult patients with primary stage II-B STS underwent limb-sparing surgery with negative microscopic margins. Eighty-eight patients (43%) received RT; 116 (57%) did not. The RT and no-RT groups were balanced with regard to age, site (upper v lower extremity), whether patients had prior unplanned excision, and location (central, i.e., shoulder/groin v non-central). The RT group had more deep tumors (P =.03). Adjuvant RT was delivered with brachytherapy in 60% and external-beam radiation in 40% of patients.

With a median follow-up of 67 months, the 5-year local control, distant relapse-free survival, and disease-specific survival rates were 82%, 80%, and 88%, respectively. There was no significant difference in local control between the RT and no-RT groups (84% v 80%, respectively, P =.3). Tumor depth, site, and prior unplanned excision did not correlate with local control. The only independent predictors of poor local control were central tumor location (relative risk [RR] = 3; 95% confidence interval [CI], 2 to 7; P =.005) and age more than 50 years (RR = 6; 95% CI, 2 to 13; P =.001).

In this retrospective study, adjuvant RT did not significantly improve local control in patients with stage II-B STS of the extremity. The outcome of patients with central tumor location was poor, and efforts to identify the optimal local treatment approach for such patients are warranted.