Pexidartinib (PLX3397, Daiichi-Sankyo) is a small-molecule receptor tyrosine kinase-inhibitor of CSF1 receptor (CSF1R), FMS-like tyrosine kinase 3 (FLT3) and stromal cell factor receptor (Kit) [7, 8], and is approved for the treatment of adults with symptomatic tenosynovial giant cell tumor (TGCT) associated with severe morbidity or functional limitations and not amenable to improvement with surgery. Here, FLT3 is linked to tenosynovial giant cell tumor.