Medullary Thyroid Cancer- Updates and Challenges.

A personalised approach to the management of Medullary Thyroid Cancer (MTC) presents several challenges, however in the past decade significant progress has been made in both diagnostic and treatment modalities. Germline RET testing in MEN 2 & 3, and somatic RET testing in sporadic MTC have revolutionized the treatment options available to patients. PET imaging with novel radioligands has improved characterization of disease and a new international grading system can predict prognosis. Systemic therapy for persistent and metastatic disease has evolved significantly with targeted kinase therapy especially for those harboring germline or somatic RET variants. Selpercatinib and pralsetinib are highly selective RET kinase inhibitors which have shown improved progression free survival with better tolerability compared to outcomes seen in earlier multikinase inhibitor studies. Here we discuss changes in paradigms for MTC patients; from determining RET alteration status upfront to novel techniques for the evaluation of this heterogenous disease. Successes and challenges with kinase inhibitor use will illustrate how managing this rare malignancy continues to evolve.