Hypophysitis and secondary adrenal insufficiency associated with Pembrolizumab

Abstract

Introduction: Immune checkpoint inhibitors (IPCI) are part of the therapeutic armamentarium against different types of solid tumors, demonstrating different usefulness in metastatic and stage III melanoma. In Colombia, for this indication, antibodies against antigen 4 of cytotoxic T lymphocytes (anti CTLA-4) and antibodies against programmed cell death receptor 1 (anti PD1) were approved. Immune-mediated adverse events have been described, being endocrinopathies one of the most frequent. Hypophysitis is frequently associated with anti-CTLA-4 therapy, the presentation being rare in patients with anti-PD-1 therapy, presenting, in the latter, more larval and nonspecific clinical pictures, although consequences can be serious.
Purpose: This article reports the case of an 81-year-old male patient with hypophysitis with grade 3 adverse reaction with adrenal insufficiency secondary to the use of Pembrolizumab, part of the treatment of a metastatic pulmonary melanoma.
Case presentation: The patient presented with general symptoms, asthenia, nausea
and hyporexia, normovolemic hypotonic hyponatremia with low cortisol levels and with inappropriately normal ACTH (adrenocorticotropic hormone). He required in-hospital management with glucocorticoids with adequate clinical and paraclinical response to treatment.
Discussion and conclusions: Immunotherapy treatments in patients with neoplastic diseaseare increasingly used and can lead to the development of adverse events. We present, in the clinical case, a pembrolizumab toxicity event causing isolated secondary adrenal insufficiency. This is an uncommon situation and usually presents with a non-specific clinical presentation, so we must have a high level of suspicion to provide adequate management; the delay in initiating corticosteroid treatment has consequences for the patient.