Endocrine Abstracts

A 42-year-old man undergoing ipilimumab therapy for stage IV metastatic melanoma presented after his third dose with vomiting, abdominal pain, hypotension, and pyrexia. He was treated as a presumed line sepsis. Four days prior to admission, thyroid function test showed T₄ of 7.9 pmol/l and TSH 0.02 mU/l and he was treated with levothyroxine. A pituitary profile was carried out on admission and the results were as follows, cortisol was 24 nmol/l, testosterone <0.2 nmol/l, LH 1.5 U/l, FSH 5.1 U/l, and prolactin 135 mU/l. Pituitary profile had been normal at start of treatment. Acting on the above results he was commenced on hydrocortisone and clinically improved rapidly. CT brain found no abnormality in the pituitary region. MRI showed an atrophic pituitary with homogenous enhancement, normal stalk and a preserved posterior pituitary bright spot. Given the finding of new pan-hypopituitarism he was treated as an adrenal crisis secondary to ipilimumab related autoimmune hypophysitis, despite lack of pituitary or stalk enlargement on imaging. There is no consensus in the literature on how to manage ipilimumab related hypophysitis. Some centres advocate high dose i.v. or oral steroids, while other centres feel that steroids do not affect the outcome. Our patient was treated with high dose i.v. methylprednisolone therapy followed by a rapidly reducing dose of oral prednisolone therapy. He had symptomatic improvement from this, but continues to demonstrate pan-hypopituitarism at assessment 3 months after treatment. This case describes adrenal crisis secondary to immune related hypophysitis caused by ipilimumab and management of it with i.v. methylprednisolone. Frequency of immunotherapy for treating solid organ tumours is increasing and clinicians need to be aware of these life threatening side effects and their treatment.