68P Perioperative chemotherapy in localized high-risk soft tissue sarcoma of the extremities: A study based on the Latin American population

The standard treatment for large, intermediate-, and high-grade extremity soft tissue sarcoma (ESTS) involves wide excision and radiotherapy. However, for those with unfavorable characteristics, the risk of distant recurrence and mortality can exceed 50%. Unfortunately, there is a lack of universally accepted data able to clarify which treatments are more effective to prevent recurrence and improve survival for high-risk group. The definition of 'high risk' is subject to debate, but tools like the SARCULATOR may assist in refining this definition.The study aims to assess the impact of perioperative chemotherapy (CTX) on patients with high-risk ESTS. 28 adult patients with high-risk ESTS (SARCULATOR OS<60%) were enrolled in the study. Data were extracted from a prospectively maintained database, augmented by a retrospective review of medical records from those who underwent neoadjuvant chemotherapy (NCT) and resection. The response to treatment was assessed using EORTC–STBSG. All 28 patients received NCT. The median age was 42 years, with 65.5% being male, and 79.3% presented with stage III disease. The most common histological subtypes were synovial sarcoma (37.9%) and liposarcoma (31%). Over a median follow-up of 17 months, the most frequently used NCT regimen was Doxorubicin/ifosfamide (69%), with the dosage intensity for 44.8% being Q4W. Concurrent radiotherapy was administered to 24 patients, 23 patients (79.3%) completed treatment, 17.2% developed Grade 3 neutropenia, and 34.5% developed Grade 2 anemia. Five patients experienced disease progression during NCT, but 20 of the 28 patients achieved limb preservation. A poorer response was observed in synovial sarcoma with a p-value of 0.034 according to EORTC–STBSG criteria. NCT is a feasible and viable treatment option. It has been less effective for synovial sarcoma, highlighting the need for further research to improve outcomes in this subgroup. Side effects from NCT were not associated with an increased mortality rate.