Isolated Adrenocorticotropic Hormone Deficiency Caused by Camrelizumab in a Patient with Lung Sarcoma: A Case Report and Literature Review

Background: Immune checkpoint inhibitors significantly increase survival in some malignant tumors, but they also lead to a variety of immune-related adverse events that affect multiple organs, including the liver, lung and endocrine system. Isolated adrenocorticotropic hormone (ACTH) deficiency (IAD) is a rare pituitary disorder characterized by secondary adrenal insufficiency with low or absent cortisol production but the normal secretion of pituitary hormones other than ACTH. IAD caused by atezolizumab, pembrolizumab and nivolumab therapy had been reported, but none is reported in camrelizumab, a new immune checkpoint inhibitor (ICI). Clinicians may not be aware of this unusual side effect. Case presentation: Here, we describe a 70-year-old male patient who had lung sarcoma and was treated with camrelizumab. After nine months of treatment, he developed immune-related pneumonia and hepatitis associated with camrelizumab. The patient discontinued the drug and recovered soon after administration of glucocorticoids. But he subsequently appeared severe hyponatremia, and was diagnosed with late-onset IAD induced by camrelizumab. His symptoms alleviated after glucocorticoid replacement therapy. Conclusion Regular monitoring serum sodium levels and testing endocrine function should be beneficial for cancer patients not only during the treatment of camrelizumab but also after discontinuation of the ICI. Clinicians should consider IAD induced by ICIs when hyponatremia occurs in the patients.