What adjuvant therapy, if any, do you consider for high grade extraskeletal osteosarcomas after R0 resection?  

Extraskeletal osteosarcoma is generally managed as other soft tissue sarcoma would be managed (as per NCCN guidelines for bone cancer Version 1.2019). For a high grade soft tissue sarcoma that has been removed with an R0 resection, radiotherapy should be considered depending on the location of the t...