Title: State of the art management of Radioactive-Iodine Refractory Differentiated Thyroid Cancer (RAI-R DTC)

Abstract:

Introduction: The treatment options for patients with radioactive iodine refractory differentiated thyroid cancer include observation, multi-tyrosine kinase inhibitors (MTKIs), and traditional chemotherapy. Appropriate initial treatment with MTKI is challenging in clinical practice that the benefits outweigh the risk of any adverse events. Treatment strategies for Radioactive-Iodine Refractory Differentiated Thyroid Cancer: The activation of multiple downstream VEGFR signaling pathways, oncogenic mutated kinases (e.g. BRAF mutations), rearrangements of RET, ALK, NTRK, and TERT promoter mutations are molecular mechanisms involved in RAI-R DTC. MTKIs demonstrated the clinical benefits of either progression-free survival (11 to 18 months) and response rate (24-63%). Sorafenib and lenvatinib were approved by the FDA for the treatment of RAI-R DTC. However, up to 60% of patients with MTKIs required a dose reduction due to adverse events (AEs). The most frequent AEs are hypertension, diarrhea, weight loss, mucositis, fatigue,hand-foot syndrome, alopecia, and diarrhea. Therefore, close monitoring for disease progression and TSH-suppressive therapy is an appropriate treatment for those patients with asymptomatic metastatic disease or slow-growing tumors. Initiation of treatment with MTKIs should be considered in symptomatic disease or a rapidly growing tumor.
Conclusions: MTKIs demonstrate a promising approach. Sorafenib and lenvatinib have been approved by the FDA for the treatment of RAI-R DTC. However, multidisciplinary evaluation for the adjustment made to take account of clinical benefits and risks should be performed before initiating MTKIs regarding potential toxicities.

Biography:

Dr. Prasongsook has completed the Thai Board of Medical Oncology from Ramathibodi Hospital, Bangkok, Thailand, then a postdoctoral research fellowship in Medical Oncology at Mayo Clinic, and a master's degree of Clinical Translational Science Program from Mayo Graduate School, Rochester, MN, USA. The current position is an assistant professor in the Medical Oncology unit at Phramongkutklao Hospital, Bangkok, Thailand. Research interests include all areas of care related to endocrine malignancies, with focusing on thyroid cancer, lung cancer, and the nutraceutical approach in cancer treatment.