Combination Therapy including Immune Checkpoint Inhibitors for Anaplastic and Poorly Differentiated Thyroid Carcinoma: A Promising Protocol

Background: Combination therapy including immune checkpoint inhibitors (ICIs) may be a promising option for patients with anaplastic thyroid carcinoma (ATC) or poorly differentiated thyroid carcinoma (PDTC). This study aimed to explore the efficacy of ICIs combined with kinase inhibitors (KIs) or chemotherapy (CT) for ATC/PDTC. Methods: The data of five patients with ATC and two patients with PDTC who received treatment of ICIs combined with CT or KIs were retrospectively analyzed. The patients' response status was evaluated by the response evaluation criteria in solid tumors (RECIST v1.1) criteria. Progression-free survival (PFS) and overall survival (OS) were also collected. Results: The overall response rate was 42.9%, including 14.3% (1/7) with a complete response and 28.6% (2/7) with a partial response, 14.3% (1/7) had stable disease. The median PFS of the included seven patients after ICIs treatment was 9 months, median OS was 17 months, and one-year OS rate was 71.43%. Notably, the condition of one patient with PDTC and brain metastasis was significantly reduced after treatment of a programmed death (PD)-1 inhibitor. However, the patient might not tolerate the side effects of CT and died three months after discontinuation of treatment, with an OS of 13 months. The other three patients were treated with ICIs when their condition was in the stage of rapid disease progression, but did not benefit from Conclusions: ICI therapy, whether combined with CT or KIs, may help achieve a better therapeutic effect than monotherapy alone. Early use of ICIs may be necessary for patients with ATC or PDTC to increase therapeutic benefits.