Endocrine Abstracts

Hypophysitis are a heterogeneous group of inflammatory lesions affecting the hypophysis. Have been described hypophysitis secondary to administration of immunomodulatory drugs such as interferon and anti-cytotoxic T lymphocyte antigen-4 antibodies (CTLA-4). Ipilimumab is an anti-CTLA-4 human monoclonal antibody that blocks the union between CTLA-4 and B7 receptor on antigen-presenting cells causing an antitumoral effect and increasing the production of autoantibodies. Hypophysitis has been described in 17% of patients treated with this drug and usually appears before the fourth dose. Clinical presentation is similar to other causes of hypophysitis.

Case report: 44 years old man. Medical history: ocular melanoma with hepatic metastases 12 years after surgery. After the 3rd cycle of treatment with intravenous Ipilimumab (3 mg/kg per 3 weeks), the patient began with intense headache. Cranial MRI showed an increased hypophysis so a morphofunctional study of hypophysis was performed. Laboratory evaluation: fasting blood glucose 76 mg/dl, creatinine 0.77 mg/dl, sodium 135 mg/dl, aspartate transaminase (AST) 80 UI/l, alanine transaminase (ALT) 311 UI/l, gamma-glutamyltransferase (GGT) 776 UI/l, TSH 0,04 μUI/ml, free T4 0.65 ng/dl, serum cortisol (0800 h) 14 μg/dl, ACTH 19 pg/dl, prolactin 8.83 ng/ml, FSH 11.97 mUI/ml, LH 3.23 mUI/ml, testosterone 1.2 ng/ml, GH 0.77 ng/ml, IGF-1 83.4 ng/ml (94–252). Pituitary MRI with contrast: glandular thickening with extension to cavernous sinus and irregular contrast enhancement. After the diagnosis of Ipilimumab-induced hypophysitis with gonadal and thyroid axis deficiency associated, Ipilimumab was stopped. The patient began levothyroxine replacement therapy and treatment with prednisone 60 mg/day, with a progressive dose decrease during a month until get the correct replacement dose.

Conclusion: The use of new immunomodulatory drugs makes necessary to identify and define this hypophysitis cause and set out protocols with the oncologists to avoid undue delay in its diagnosis and treatment.