OBJECTIVES: Soft tissue sarcomas (STS) are a heterogeneous group of rare and often malignant tumors that originate from mesenchymal tissue. More than 50% of STSs develop in an upper or lower extremity. The objective of this research was to examine the literature to identify patient-reported outcome (PRO) symptom measures used in STS patients and if needed, develop a disease-specific symptom inventory for STS subtypes: leiomyosarcoma, synovial sarcoma, liposarcoma, and undifferentiated sarcoma. METHODS: Literature review and clinical expert and patient interviews were conducted to determine disease-specific symptoms important to patients with one of the four STS subtypes. Very few PRO symptom instruments (n=5) were found in the STS clinical trial literature. Clinical experts identified the most relevant STS symptom items from the EORTC QLQ-C30, MDASI, MSAS, PRO-CTCAE, and 3-item STS symptom measure. STS patients were recruited from patient registries, panels, and advocacy groups. A symptom list was presented to patients in qualitative interviews and via web survey to identify items for the STS-specific symptom inventory. RESULTS: Ninety symptom items were compiled and discussed with three clinical experts who identified 24 symptoms specific to the four STS subtypes. An electronic survey was created for patient review. Ten patients (with a goal of 12) were interviewed and an additional 26 patients completed the electronic survey to provide information for selection of symptoms for and development of the STS-specific symptom inventory.  CONCLUSIONS: No disease-specific PROs and very little information on symptoms relevant to STS patients exist. PROs can be used as a valuable tool in RCTs and by physicians to assess issues associated with STS. Next steps include collecting additional item pool data from patients with STS and using the draft STS item pool in an RCT.