KDR and osteosarcoma: Treatment with VEGFR thymidine kinase inhibitors in combination with immune checkpoint inhibitors has improved outcomes in RCC, HCC, and NSCLC; mucosal melanoma, endometrial carcinoma, esophageal carcinoma, triple-negative breast cancer, microsatellite stability GC, and CRC; and head and neck squamous cell carcinoma, urothelial carcinoma, osteosarcoma, and other malignant tumors [24].