Poorly differentiated thyroid carcinoma (PDTC) characteristics and the efficacy of radioactive iodine (RAI) therapy as an adjuvant treatment in a tertiary cancer care center

Background Poorly differentiated thyroid cancer (PDTC) is biologically more aggressive. Surgery remains the mainstay of treatment. The utility of radioactive iodine (RAI) after surgery is unclear. Methods In this retrospective study, patients treated between Jan 2012 and Dec 2017 were included. The demographic, clinical and treatment-related details, including RAI ablation, were recorded and their survival analyzed. Results Thirty-five patients fulfilled the eligibility criteria. Majority was treatment naive at presentation. All patients underwent surgery followed by RAI ablation, with a cumulative median dose of 220 mCi (range 40-1140). Sixteen patients received more than one radioiodine treatment for distant metastases. Incomplete resection, age > 45 years and the presence of distant metastasis influenced survival the most. The 3-year PFS of patients with PDTC was 69%. Conclusion All patients in our series showed uptake and responded to treatment. Further use of molecular markers and functional molecular imaging would better our understanding of this entity.