178 Background: Soft tissue sarcoma is a rare disease requiring multidisciplinary care for effective treatment. The National Comprehensive Cancer Network has developed guidelines for surgical resection and adjuvant therapy based on best available evidence. We sought to examine variance from these guidelines in treatment across the United States. Methods: The Surveillance, Epidemiology and End Results cancer registry was queried to identify patients undergoing surgery for extra-abdominal soft tissue sarcoma from 2004-2009. Coded variables signifying radical excision (RE) and the use of radiation therapy (RT) were correlated with stage of the primary tumor. Patients with metastatic disease, unknown size and unknown grade were excluded. Results: A total of 5,600 patients were identified with a median age of 61. Median tumor size was 8cm and most tumors were high grade (57% G3). Stage specific breakdown was as follows; Stage I 24%, Stage II 37% and Stage III 39%. Overall, 54% of patients underwent RE and 50% received RT, mostly in the post-operative setting (83%). The amputation rate was 4%. Although routine radiation therapy is not recommended for Stage IA and IB patients, 24% still underwent RT, whereas only 49% of Stage I patients were noted to have undergone a RE. Even though routine RT is recommended for Stage II and III tumors, 42% of patients did not undergo any RT, and only 58% underwent RE. On multivariate analysis predictors of RE were age <50 (OR 1.3, 95% CI 1.1-1.6), lower extremity tumor (OR 2.2, 95% CI 1.6- 2.8), Stage III, (OR 2.1, 95% CI 1.7- 2.6), and white race (OR 1.4, 95% CI 1.2- 1.8). Variance from guidelines was seen in 64% of patients. Conclusions: Significant heterogeneity and variation in the contemporary treatment for soft tissue sarcoma in the United States exists. Although low rates of RE may be related to coding discrepancies, rates as low as 54% are still a cause for concern. Overuse, and more importantly, underuse of RT is seen for a significant proportion of patients. If these trends are confirmed by further study, more effort will have to be directed towards compliance with appropriate treatment recommendations, perhaps by regionalizing sarcoma care.