Endocrine Abstracts

Introduction: Hypophysitis is a rare disease. Lately, it is more frequent due to the use of Inmune Check Point Inhibitor (ICPIs). Ipilimumab or combo Ipilimumab + Nivolumab are the main cause. Agree with literature, 17-18% of the patients with these drugs suffer from. By contrast, with Idiopatic Autoimmune Hypophysitis and Lymphocytic Hypophysitis, this type of hypophysitis occurs in sixties men. Autoinmunity mechanism is known, but precise pathophysiology is unclear

Case: A seventy-four years old man diagnosed renal carcinoma (T3NxMx) seven years ago. In 2023, a progression lymphatic nodal mediastinal and lung micrometastasis were confirmed. Consequently, he received first line treatment with Ipilumab-Nivolumab. Twelve weeks later, previous to filth cycle, he had a syncopal crisis with hypotension and bradycardia. Moreover, the patient referred to feel cold, mental slowing, constipation and visual disturbances one month ago. Also, sickness and weakness two weeks ago. Urgently stress dose of Hydrocortisone was started. Finally, analytics confirmed the diagnosis: 0,1 mg/dl cortisol, Na 133,4 mmol/l, K 3,51 mmol/l. TSH 0,06 mcUI/ml, T4L 0,93 ng/dl, T3L 4,54 ng/dl. Rest of pituitary hormones are regular. So, Levotiroxina was started too. Magnetic Resonance showed pituitary enlargement. One month later, the patient refers visual deficit had corrected. Overall status of the patient is better and blood pressure is normal. In the analytics, hypocortisolism and hypothyroidism are with replacement treatment correctly. Three months later, Magnetic Resonance showed pituitary smaller and partial empty sella. On the other hand, lung micrometastasis disappeared and lymphatic nodal mediastinal were stabled. So, the patient received fifth cycle of Ipilimumab-Nivolumab

Conclusion: - Nowadays, hypophysitis is more frequent in Oncology Patients. - The main immune-related adverse effects (IrAE) produced by CTLA-4 inhibitor (Ipilumumab) is hypophysitis - According to literature, Hypophysitis secondary to Ipilimumab-associated is a clinical entity distinct from anti-PD-1 hypophysitis (Nivolumab, Pembrolizumab) - In our case the diagnosis did when four treatment cycles were received, according to literature. - Hormonal deficiency more frequent is ACTH, followed to TSH and FSH/lH - IrAE due to Ipilimumab-Nivolumab need hormonal treatment by long term, permanently in most cases. - Recognition and timely diagnosis of these patients avoid unnecessary potential effects on morbidity and mortality from untreated adrenal insufficiency and stopping ICPIs