SSO recently endorsed the new clinical guideline from the American Society for Radiation Oncology (ASTRO) that provides guidance on the use of radiation therapy to treat adult patients with soft tissue sarcoma (STS). Recommendations outline optimal radiation dosing, techniques and treatment planning for patients with localized, operable STS of the trunk (i.e., chest wall, abdominal wall) and extremities (i.e., arms, legs), with a focus on preserving long-term functionality through individualized care. The guideline additionally addresses the role for radiation therapy for retroperitoneal sarcoma.
Recommendations in the guideline address patient selection for radiation therapy and outline best practices for dosing, sequencing, planning and image guidance for extremity and superficial truncal STS, as well as for retroperitoneal sarcomas, which offer a worse prognosis than those in the extremities. The guideline also calls attention to the fundamental role that cooperation between the multidisciplinary care team has in the design and delivery of patient care. Key recommendations are as follows:
- Radiation therapy is recommended for patients with primary, localized extremity and truncal soft tissue sarcomas who are at increased risk of local recurrence, based on multidisciplinary evaluation of the tumor’s pathology, location and size; final or expected surgical margins; and other factors that are detailed in the guideline. Radiation therapy generally is not recommended for patients at low risk of local recurrence.
- For patients where surgery and radiation therapy are indicated, preoperative radiation therapy is recommended. Postoperative radiation therapy is recommended only in specific clinical circumstances, such as the discovery of unanticipated adverse pathologic features following oncologic resection or unplanned excision, or when the risk of wound healing complications outweighs the risk of long-term, permanent side effects. The guideline also includes treatment algorithms for initial local management and local management following an unplanned excision.
- For patients with primary localized retroperitoneal sarcomas (RPS), the routine use of radiation therapy in addition to oncological resection is conditionally not recommended. Selective use of radiation therapy may be considered for patients with RPS at high risk of local recurrence. When radiation therapy is indicated in these select cases, preoperative radiation is preferred.
- The guideline addresses optimal dosing, fractionation, target delineation and delivery techniques for preoperative and postoperative radiation therapy, including recommendations for image guidance and patient positioning, with specific attention to patients’ long-term functional outcomes.
The guideline was based on a systematic literature review of articles published from January 1980 through September 2020. The multidisciplinary task force included radiation, medical, orthopedic and surgical oncologists, a radiation oncology resident, a pathologist, a medical physicist and a patient representative. SSO appointed members of the SSO’s Sarcoma Disease Site Work Group to participate in the multidisciplinary task force that developed the guideline, as well as conduct an expert peer review. In addition, members of the SSO Quality Committee reviewed the guideline, which was approved for endorsement by the SSO Executive Committee.