['Evolving evidence suggests that, in selected patients with tumour category 1 (T1) extremity soft tissue sarcoma (ESTS), surgery alone offers satisfactory results without decreasing survival. This study assessed the effect of sarcoma treatments on survival outcomes of T1 ESTS in a population-based data set.', 'Using the Surveillance, Epidemiology, and End Results database, 1618 patients with primary ESTS underwent limb-sparing surgery. Multivariable analysis was used to assess the impact of radiotherapy on overall survival (OS) and sarcoma-specific survival (SSS), adjusting for co-variables.', 'Some 803 patients (49.6 per cent) underwent surgery alone for T1 ESTS. Radiotherapy in patients with low- and high-grade tumours did not result in any significant difference in OS or SSS. When stratified by grade, multivariable analysis showed that adjuvant radiotherapy was not an independent predictor of SSS (hazard ratio (HR) 1.05; P = 0.906) or OS (HR 0.89; P = 0.695) in low-grade tumours. Neither was radiotherapy a significant predictor of SSS (HR 0.87; P = 0.608) or OS (HR 0.67; P = 0.071) in high-grade tumours.'] Is surgery alone adequate treatment for early stage soft tissue sarcoma of the extremity?