Hypophysitis induced by immune checkpoint inhibitors in a Scottish melanoma population: Immune checkpoint inhibitor toxicity

Aim: This study aims to determine the incidence of all immune-mediated adverse events (IMAEs) with a focus on hypophysitis in patients with metastatic melanoma receiving immune checkpoint inhibitors (ICI). Methods: 51 patients with metastatic melanoma who received immune checkpoint inhibitors (ipilimumab, pembrolizumab and nivolumab) in Ninewells Hospital, Dundee between 2014 and 2018 were identified. Patient demographic data and outcomes were recorded retrospectively. Results: A total of 6 patients (11.7%) developed hypophysitis, while 15 patients (29.4%) developed IMAEs. A significant improvement in overall survival (p = 0.03) and progression-free survival (p = 0.041) was seen in patients who developed IMAEs compared with those who did not. Conclusion: This study demonstrates a high rate of hypophysitis in melanoma patients receiving ipilimumab. Careful monitoring of symptoms is crucial to detect and appropriately manage IMAEs.