NTRK and RET-fusion directed therapy in pediatric thyroid cancer yields tumor response and radioiodine uptake

The molecular characteristics driving oncogenesis in pediatric papillary thyroid cancer (PTC) are distinct from adult PTC, and are important for developing new molecularly targeted therapies for progressive 131I-refractory PTC.Among about 100 pediatric patients, Genetic analysis was performed using whole genome sequencing (WGS), targeted sequencing, RNA sequencing, direct sequencing, FISH, and/or IHC according to the availability of each tissue .PTC fusion oncogenes are predominantly found in young children, in association with 131I-refractory advanced disease. Selective fusion-directed therapy may restore radioiodine avidity and lead to dramatic tumor response, underscoring the importance of molecular testing in pediatric PTC patients.