Endocrine Abstracts

Introduction: There has been an increase in the use of new drugs called immune checkpoint inhibitors (ICPI) used in advanced tumors. Clinical trials have also reported an increased risk of developing immune-related adverse events (IRAEs). Endocrine IRAEs may be particularly relevant.

Material and Methods: This is a retrospective study. Patients treated with ICPI were obtained from Medical Oncology departament of the General University Hospital of Albacete from January 2016 to January 2019. We studied demographic and data related to the tumor, ICPI used, the appearance of thyroid function changes during treatment with the drug, as well as number of cycles received and time elapsed until endocrinopathy. The objective of our study was to analyze the appearance of endocrinopathies and the time that elapses until their appearance.

Results: Our sample size was 107 patients: 75 were treated with nivolumab, 19 with pembrolizumab, 8 with atezolizumab and 5 with ipilimumab. 31% were women and 69% men. The average age at diagnosis was 60 years old. The most frequent location of the primary tumor was the lung. Alteration of thyroid function was observed in 24 patients (22%) treated with ICPI. The most frequent thyroid disorder was subclinical hypothyroidism in 11 cases (46%), followed by primary hypothyroidism in 7 patients (29%) and, finally, silent thyroiditis in 6 of them (25%). The average number of cycles received until developing endocrinopathy was 6 and the time elapsed 12.4 weeks.

Conclusions: Thyroid disorders are usual in cancer patients treated with ICPI. The most frequent thyroid disorder is subclinical hypothyroidism. It is advisable to monitor thyroid function in patients treated with these drugs.