Background: The role of neoadjuvant chemotherapy (NCT) for high-risk soft tissue sarcoma (STS) is questioned. This study aimed to define which patients may experience a survival advantage with NCT.
Methods: All the patients from the U.S. Sarcoma Collaborative database (2000-2016) who underwent curative-intent resection of high-grade, primary truncal/extremity STS size 5 cm or larger were included in this study. The primary end points were recurrence-free survival (RFS) and overall survival (OS).
Results: Of the 4153 patients, 770 were included in the study. The median tumor size was 10 cm, and 669 of the patients (87%) had extremity tumors. The most common histology was undifferentiated pleomorphic sarcoma (UPS), found in 42% of the patients. Of the 770 patients, 216 (28%) received NCT. The patients who received NCT had deeper, larger tumors (p < 0.001). Of the patients with tumors 5 cm or larger and 8 cm or larger, NCT was not associated with improved RFS or OS. However for the patients with tumors 10 cm or larger, NCT was associated with improved 5-year RFS (51% vs 40%; p = 0.053) and 5-year OS (58% vs 47%; p = 0.043). By location, the patients with extremity tumors 10 cm or larger but not truncal tumors had improved 5-yearr RFS (54% vs 42%; p = 0.042) and 5-year OS (61% vs 47%; p = 0.015) with NCT. According to histology, no subtype had improved RFS or OS with NCT, although the patients with UPS had a trend toward improved 5-year RFS (56% vs 42%; p = 0.092) and 5-year OS (66% vs 52%; p = 0.103) with NCT.
Conclusion: For the patients with high-grade STS, NCT was associated with improved RFS and OS when tumors were 10 cm or larger and located in the extremity. However, no histiotype-specific advantage was identified. Future studies assessing the efficacy of NCT may consider focusing on these patients, with added focus on histology-specific strategies.