Neoadjuvant tyrosine kinase inhibitor therapy in locally advanced differentiated thyroid cancer: a series

Abstract

IntroductionLocally advanced differentiated thyroid cancer (LADTC) management depends on a complex interplay of patient and tumour factors. When primary resection cannot be achieved, neoadjuvant tyrosine kinase inhibitor (TKI) therapy can be considered, but little evidence is available on its success and outcomes. Our aim was to describe a small series of LADTC managed with neoadjuvant TKI therapy.MethodsSuitable patients were prospectively identified in NHS Lothian February 2016 – March 2020.ResultsFour patients were eligible for inclusion, 3 females; 1 male, aged 39–79 years. All were T4a at presentation; three papillary and one Hurthle cell carcinoma. One had pulmonary metastases. Two refused laryngectomy, one was deemed unresectable with extensive tracheal involvement, and one commenced TKI due to COVID-19 related surgical delay. TKI treatment length varied from 1–18 months. There was a marked reduction in tumour volume and local extent in three cases, such that surgical resection without laryngectomy could be achieved. The fourth patient was intolerant of TKI. All ceased TKIs 2 weeks prior to total thyroidectomy, with neck dissection in three, and tracheal resection and re-anastomosis in two. All then had 3700MBq RAI and all patients are currently alive with 14–58 months follow-up. Two patients have no evidence of residual or recurrent disease. The M1 patient has stable low-volume local and distant disease, and one patient has stable low volume indeterminate pulmonary nodules.ConclusionNeoadjuvant TKI therapy in LADTC can be effective in reducing primary tumour extent to potentially facilitate limited surgical resection in a highly selected patient group.