Endocrine Abstracts

Background: Immune checkpoint inhibitors have demonstrated significant advances in the treatment of several cancers including metastatic melanoma. However, they are frequently associated with immune-related adverse events which often require treatment with prolonged courses of glucocorticoids. Long-term glucocorticoid use is associated with several side effects including hyperglycaemia.

Aims: 1) To determine the prevalence of glucocorticoid use in patients treated with immune checkpoint inhibitors for melanoma.

2) To determine the cumulative dose and duration of glucocorticoid (as prednisolone equivalent) given to patients for treatment of immune-related adverse events.

3) To determine the prevalence of new onset hyperglycaemia in patients treated with glucocorticoids.

Methods: Retrospective review of patients with advanced melanoma treated with an immune checkpoint inhibitor between September 2010 and January 2017 at the Royal Marsden Hospital, London. The electronic patient record was used to identify patients treated with glucocorticoids, to determine the cumulative dose and duration of glucocorticoid treatment and to determine the number of patients developing new onset hyperglycaemia.

Results: 412 patients received immune checkpoint therapy, with 157 (38%) requiring glucocorticoids to treat immune-related adverse events. The median cumulative glucocorticoid dose was 2795 mg (prednisolone equivalent) with a median duration of 61 days. After excluding patients with pre-existing diabetes, 20% of patients receiving glucocorticoids were noted to develop new onset hyperglycaemia. A statistically significant difference was found in the median cumulative dose and duration of glucocorticoid treatment between patients who developed new onset hyperglycaemia and those who did not (P<0.0001).

Conclusions: Immune-related adverse events frequently occur in patients treated with immune checkpoint inhibitors. Consequently, patients typically receive high doses of glucocorticoids for prolonged durations, often resulting in glucocorticoid-induced hyperglycaemia. Given the doses used, many will also be at risk of adrenal suppression. Endocrinologists therefore need to be aware of these emerging indications for prolonged glucocorticoid treatment in the oncology setting.