Larotrectinib efficacy for liver metastases in papillary thyroid carcinoma patient harboring SQSTM1-NTRK1 fusion.

In conclusion, larotrectinib demonstrated effective antitumor activity against liver metastases of PTC, a relatively rare site of distant metastasis. Furthermore, the efficacy of larotrectinib was maintained, even though the patient had a history of multi-tyrosine kinase inhibitor treatment and a relatively infrequent fusion gene, SQSTM1-NTRK1.