NTRK3 and nodular fasciitis: Although the differential diagnosis includes other myofibroblastic lesions (e.g. desmoid-type fibromatosis, nodular fasciitis, infantile fibrosarcoma) and deep benign fibrous histiocytoma/cellular dermatofibroma, the typical biphasic pattern and the myxohyaline matrix of myofibromas is not observed in these lesions and genetic changes are different (desmoid: beta-catenin mutations; nodular fasciitis: USP6-rearrangements, infantile fibrosarcoma: ETV6-NTRK3 fusion) [4].