FLT3 and synovial sarcoma: The initiating factor of SS, with classic SS as the pathomechanism’s prototype, has yet to be established, although the action of certain medications, such as granulocyte colony stimulating factors (G-CSF), all-trans retinoic acid (ATRA) or FMS-like tyrosine kinase-3 (FLT3) inhibitors offer a starting hypothesis in cases of hematologic malignancy [13].