Many children with bone and soft tissue cancers are not cured and will die. Immune checkpoint inhibitors are medications that cause white blood cells in a patient (called T-cells) to kill cancer cells. They are safe in children but have not been shown to kill pediatric solid tumors when given alone, because these tumors do not have a lot of T-cells. In order to improve the action of checkpoint inhibitors against pediatric solid tumors, another treatment needs to be added to increase the number of T-cells in the tumor.
Cryoablation therapy involves inserting a needle into a tumor to freeze and kill tumor cells. It causes T-cells to enter tumors and may help checkpoint inhibitors kill tumors. In this study, patients up to age 40 years with pediatric solid tumors that come back and spread after treatment will receive checkpoint inhibitors nivolumab and ipilimumab and undergo cryoablation therapy to one tumor target. We will study three of the most common types of solid tumors in children: osteosarcoma, Ewing sarcoma, and rhabdomyosarcoma. We will follow the tumors over time to see if they shrink. We believe the cryoablation will help checkpoint inhibitors kill the tumor that received cryoablation as well as other tumors due to the immune system’s response. We will also test tumor tissue and blood from patients before and during treatment to examine how the treatment affects white blood cells in the body and help the immune system to fight the tumor. Although cryoablation and checkpoint inhibitors have been found to be a safe therapy individually for children, this is the first known clinical trial studying this combination in children. We expect that this combination will be safe and effective in children with solid tumors.
If the combination of checkpoint inhibitors and cryoablation therapy is found to be safe and effective, it will be a promising new treatment for children with cancer.