Selpercatinib Pre-RAI in Patients With RET Fusion Thyroid Cancer (RAISE)

This study (RAISE) is testing whether a targeted drug called selpercatinib can help prepare the thyroid cancer to better respond to radioactive iodine treatment (RAI) — a common therapy for thyroid cancer — in young patients whose cancer has a specific genetic mutation called a RET fusion. **You may be eligible if...** - You are between 2 and 25 years old - You have been diagnosed with differentiated thyroid cancer after thyroidectomy (thyroid removal) - Your cancer has a RET gene fusion mutation - Your chest CT shows multiple small lung nodules or other evaluable disease meeting specific criteria **You may NOT be eligible if...** - You are outside the 2–25 age range - Your cancer does not have a RET fusion - Your disease does not meet the imaging criteria at enrollment Talk to your doctor to see if this trial is right for you.