A randomized, non-comparative phase 2 study of neoadjuvant immune-checkpoint blockade in retroperitoneal dedifferentiated liposarcoma and extremity/truncal undifferentiated pleomorphic sarcoma
This study was partially funded by SFA. In the paper entitled “A randomized, non-comparative phase 2 study of neoadjuvant immune-checkpoint blockade in retroperitoneal dedifferentiated liposarcoma and extremity/truncal undifferentiated pleomorphic sarcoma,” the investigators conducted a randomized, non-comparative phase 2 trial ( NCT03307616 ) of neoadjuvant, or pre-surgical, immune checkpoint blockade, or ICB, (nivolumab or nivolumab/ipilimumab), which removes the “brakes” that tumors put on the immune system, in patients with resectable retroperitoneal dedifferentiated liposarcoma (DDLPS) and extremity/truncal undifferentiated pleomorphic sarcoma (UPS). The patients with UPS received radiation therapy along with the immune checkpoint blockade. The primary end point of pathologic response was a median of 8.8% in DDLPS and 89% in UPS. Lower densities of immune cells called regulatory T cells in the tumor before treatment were associated with a major pathologic response. Additionally, increased numbers of a different kind of immune cells called B cells in tumors following neoadjuvant treatment was associated with overall survival in DDLPS. This research shows that neoadjuvant ICB is associated with how the immune system interacts with the tumors in DDLPS and UPS and that neoadjuvant ICB along with radiotherapy has significant efficacy in UPS, however additional studies need to be done before this treatment is routinely used for patients with these sarcoma subtypes.