Intraoperative Radiotherapy Without External Beam Radiotherapy in the Management of Primary Soft Tissue Sarcomas of the Extremities

Abstract

Intraoperative radiation therapy (IORT) is frequently used in conjunction with conventional external-beam radiation therapy (EBRT) to treat soft tissue sarcomas (STS) of the extremities as part of a limb sparing approach. We sought to investigate the efficacy of limb preservation surgery and IORT alone in the management of primary extremity STS. This is a single institutional retrospective study of patients diagnosed with primary STS of the extremity who received surgery and IORT without neoadjuvant or adjuvant EBRT between January 2008 and April 2018. Survival analyses were performed using the Kaplan-Meier method with log-rank testing for significance. Adverse event data were assessed per CTCAE v5 guidelines. Thirty-two patients were diagnosed with primary extremity STS and underwent limb sparing surgery and IORT without neoadjuvant or adjuvant radiotherapy. Four (12.5%) patients received neoadjuvant chemotherapy and two (6.3%) received chemotherapy in the postoperative setting. Twenty-five patients (78%) had Stage I-II disease, 63% of tumors were intermediate or high grade, and 91% had negative resection margins. With a median follow up of 5.3 years, the 5-year local recurrence rate was 9.1%, and the 5-year overall survival rate was 97%. Overall, treatment was well tolerated: the most common adverse effects included postoperative infections (12.5%), grade 1 neuropathies (9.4%), and delayed wound healing (9.4%). With respect to Grade 3-5 toxicities, one Grade 3 (infection) and one Grade 5 toxicity (in a 95-year-old patient with unfavorable preoperative performance status) were observed. Limb preservation surgery and IORT alone may provide adequate local control in the management of select primary extremity STS, with acceptable toxicity.