[Clinical characteristics and risk factors of programmed death-1 inhibitors associated with thyroid gland injury].

To investigate the clinical characteristics and related risk factors of thyroid gland injury (TGI) in patients with a malignant tumor treated with a programmed death-1 (PD-1) inhibitor. A Retrospective case-control study. Data from 198 patients with a malignant tumor who received treatment with a PD-1 inhibitor in Chinese PLA General Hospital from October 2019 to October 2021 were collected and analyzed retrospectively. According to the TGI incurred after receiving treatment with a PD-1 inhibitor, patients were divided into a thyroid gland normal (TGN) group and TGI group. The prevalence, type, time of occurrence, and outcome of TGI were analyzed. The risk factors that may contribute to TGI were analyzed further by logistic regression. TGI prevalence was 29.8% (59/198 cases) after treatment with a PD-1 inhibitor. There were significant differences with respect to previous radiotherapy and targeted therapy between the TGN group and TGI group (<0.01 for both), but there were no significant differences with regard to sex, age, tumor type, previous surgery, previous chemotherapy, tumor metastasis, or type of PD-1 inhibitor (>0.05 for all). Patients in the TGI group included those with subclinical hypothyroidism (32.2%, =19), hypothyroidism (27.1%, =16), thyrotoxicosis (23.7%, =14), subclinical thyrotoxicosis (10.2%, =6), and thyroiditis with normal thyroid function (6.8%, =4), and the median time of occurrence (months) was 3.00, 3.00, 1.50, 1.50, and 0.80 after treatment with a PD-1 inhibitor, respectively. Among 20 patients who presented initially with thyrotoxicosis or subclinical thyrotoxicosis, 12 cases developed hypothyroidism or subclinical hypothyroidism subsequently. Logistic regression analysis suggested that previous radiotherapy (=3.737, 95% 1.390-10.046), targeted therapy (=3.763, 95% 1.553-9.117), thyroglobulin antibodies at baseline (=12.082, 95% 1.199-121.775), and thyroid-peroxidase antibodies at baseline (=10.874, 95% 1.010-117.047) were risk factors associated with the TGI caused by treatment with a PD-1 inhibitor. After treatment with a PD-1 inhibitor, TGI prevalence was high, especially in those with hypothyroidism or subclinical hypothyroidism. Some patients had a transition from thyrotoxicosis to hypothyroidism. Patients who underwent radiotherapy previously, had targeted therapy, or were thyroid autoantibody-positive at baseline may carry an increased risk of TGI following treatment with a PD-1 inhibitor.