A 26-year-old male with advanced TPM4-NTRK1 rearranged spindle cell neoplasm and liver, lung and bone metastases, treated with larotrectinib on a continuous 28-day schedule, and showed tumor shrinkage in both visceral and bone lesions after 7 days of treatment (45). Here, NTRK1 is linked to spindle cell neoplasm.