I can provide some information on the treatment my son received (he was diagnosed with synovial sarcoma just over four years ago (and is now clear on all his scans with no signs of recurrence) at the age of 5).
Following his initial diagnosis (which was based upon a tumor in his hip), there were signs of nodules in his lungs on some of his scans. They were very small, but were considered a possible sign of metastasis. His oncology team at Sloan Kettering suggested that he pursue full lung radiation in addition to the 'standard' protocol for his diagnosis (tumor excision, chemotherapy (ifosfamide and doxorubicin), and radiation to the tumor site). We sought input from other sources, including at Dana Farber, and were provided conflicting guidance on whether this was considered a good treatment decision. In our case, it was unclear whether the nodules shown on his lungs (which did not appear in later scans prior to his full lung radiation) were not potentially a false positive.
Ultimately, we decided to pursue full lung radiation, which was completed shortly after his last rounds of chemotherapy (and following radiation treatment to his tumor site).
It's difficult to summarize this in this type of forum. I just wanted to share a bit of information on the treatment he followed.
All the best to you.
Brian (father of Ian)