Benefit of intensified perioperative chemotherapy within high-risk CINSARC patients with resectable soft tissue sarcomas (CIRSARC)

TPS11078 Background: We have recently identified a gene expression signature so called “CINSARC” which is related with chromosomal instability and highly predictive of metastasis-free and overall survival in soft-tissue sarcoma (STS) patients. The prognostic relevance of this signature has been validated recently in an independent set of sarcomas from the Cancer Genome Atlas (TCGA) consortium. Despite optimal locoregional treatment, patients with high-risk CINSARC have a very poor outcome.However, the main issues with peri-operative chemotherapy in STS patients are the identification of patients who are more likely to benefit from this approach and the characterization of the best chemotherapy regimen. Indeed, in all clinical trials investigating peri-operative chemotherapy in STS, patients were included on the basis of classical histological criteria (grade, tumor size, deep location). The CINSARC is more discriminant than grade to evaluate the prognosis of STS patients (35% of grade 3 are low-risk CINSARC and 40% of grade are high-risk CINSARC). We hypothesize than: (1) 6 cycles of anthracyclines-ifosfamide is associated with improved outcome in comparison to 3 cycles of chemotherapy (ISG-STS 10-01) in patients with high-risk CINSARC STS; (2) Chemotherapy-free strategy is not associated with detrimental outcome in low-risk CINSARC STS. Methods: This is a multicenter phase III trial (sponsor: Institut Bergonié) which aims to evaluate the efficacy (intent-to-treat analysis) of 6 cycles of neoadjuvant doxorubicin + ifosfamide based chemotherapy+ surgery +/-radiotherapy (Arm B) in comparison with 3 cycles of neoadjuvant doxorubicin + ifosfamide based chemotherapy + surgery +/- radiotherapy (Arm A) in terms of 3-year progression-free survival (PFS) in high-risk CINSARC patients with resectable STS. Patients with low-risk CINSARC signature will be treated at investigator discretion. 334 patients will have to be recruited over 36 months in 10 centers of the French Sarcoma Group. This is the first study assessing the impact of peri-operative chemotherapy in STS based on a prognostic molecular signature. The study is open for accrual at time of submission. Clinical trial information: NCT03805022.