Abstract: Anaplastic thyroid carcinoma (ATC) is a rare and highly aggressive fatal tumor. Most ATC patients using traditional surgery or radio-chemotherapy have poor prognosis and experience recurrence in a very short time. There is no optimal therapy for ATC, and the median survival time is about 5 months. We report a 67-year-old ATC patient, who experienced rapid local recurrence after radical thyroidectomy. The resected tumor tissue was sent for immunohistochemistry analysis and targeted next-generation sequencing. The results indicated high PD-L1 expression, a tumor mutation burden of 0.48 muts/Mb, microsatellite stable, and somatic mutations of TERT  promoter, EIF1AX, NRAS  and TP53 . However, none of the mutations indicated corresponding target therapy. An immediate operation was unsuitable because of rapid recurrence after surgery. The patient was also not in a condition to tolerate chemotherapy. Based on the high expression of PD-L1, an optimum strategy was used, combining immunotherapeutic agent, sintilimab, with an anti-angiogenesis drug, anlotinib. The patient obtained remarkable tumor shrinkage and an 18.3-month-sustained remission period. This is an effective case of using immunotherapy and anti-angiogenesis agent in the first-line treatment of ATC. It demonstrates a feasible and novel therapeutic option for future treatment of ATC patients.
Keywords: anaplastic thyroid carcinoma, PD-1 inhibitor, anti-angiogenesis drug, TERT  promoter mutations, TP53 mutations, NRAS  mutation, next-generation sequencing