Efficacy and Safety of Pazopanib in the Treatment of Thyroid Cancer: A Systematic Review.

Pazopanib, a multi-targeted tyrosine kinase inhibitor, has been explored for its efficacy in treating various subtypes of thyroid cancer, including differentiated thyroid carcinoma (DTC), medullary thyroid carcinoma (MTC), and anaplastic thyroid carcinoma (ATC). This systematic review assesses the efficacy and safety of pazopanib, focusing on the progression-free survival (PFS), overall survival (OS), and response rates and adverse events. A comprehensive search was conducted in databases including PubMed, Scopus, and Web of Science up to October 2024 to identify randomized controlled trials and phase II clinical trials that investigated the use of pazopanib in thyroid cancer. The PRISMA guidelines were followed for data extraction and quality assessment. The review included six studies encompassing 289 patients, presenting a comprehensive overview of pazopanib's application across different thyroid cancer subtypes. The studies reported median PFS rates ranging from 2.1 to 11.7 months and median OS rates ranging from 5.7 months to not reached. The partial response rates varied from 5% to 49%. Adverse events were common, with hypertension occurring in up to 71.7% of patients, and fatigue and diarrhea were also frequently reported. Grade 3-5 adverse events led to treatment discontinuations in up to 14% of patients. Pazopanib shows variable efficacy across thyroid cancer types, offering significant benefits in MTC and refractory DTC in terms of PFS and OS but limited impact in ATC. The adverse event profile necessitates careful management, particularly regarding hypertension and other treatment-related toxicities. Further studies are required to refine the therapeutic protocols for pazopanib, exploring combination therapies that may enhance its efficacy and reduce the adverse outcomes.