Clinical Utility of Osilodrostat in Cushing's Disease: Review of Currently Available Literature.

Cushing's disease (CD) is caused by endogenous hypercortisolism as a result of adrenocorticotropin (ACTH) secretion from a pituitary tumor. The condition is associated with multiple comorbidities and increased mortality. First-line therapy for CD is pituitary surgery, performed by an experienced pituitary neurosurgeon. Hypercortisolism may often persist or recur after initial surgery. Patients with persistent or recurrent CD will generally benefit from medical therapy, often administered to patients who underwent radiation therapy to the sella and are awaiting its salutary effects. There are three groups of medications directed against CD, including pituitary-targeted medications that inhibit ACTH secretion from tumorous corticotroph cells, adrenally-directed medications that inhibit adrenal steroidogenesis and a glucocorticoid receptor (GR) antagonist. The focus of this review is osilodrostat, a steroidogenesis inhibitor. Osilodrostat (LCI699) was initially developed to lower serum aldosterone levels and control hypertension. However, it was soon realized that osilodrostat also inhibits 11-beta hydroxylase (CYP11B1), leading to a reduction in serum cortisol levels. The focus of drug development then shifted from treatment of hypertension to treatment of hypercortisolism in CD. In a series of studies (LINC 1 through 4), osilodrostat was shown to be effective in normalizing 24-h urinary free cortisol (UFC) in the majority of treated patients and was approved for patients with CD who have failed surgery or are not surgical candidates. Further study is needed to examine the role of combination therapy as well as long-term outcomes of treated patients. Osilodrostat was shown to have an overall good safety profile. Most common adverse effects include nausea, headache, fatigue, arthralgias, dizziness, prolonged QTc interval, hypokalemia. In females, the drug can cause hirsutism and acne. Osilodrostat is administered twice daily, making it a good choice for patients with difficulty adhering to more complex regimens. Osilodrostat has an important, albeit adjunctive, role in the management of patients with CD.

Recurrent Acromegaly in a Patient With a CHEK2 Mutation.

Background/Objective: CHEK2 is a cell-cycle checkpoint kinase and is part of the ATM-CHEK2-p53 cascade, which is protective against carcinogenesis. We describe a germline CHEK2 mutation in a patient with acromegaly and other tumors. Case Report: We present a woman with a germline CHEK2∗ 110delC mutation previously diagnosed with fibroadenoma of the breast and papillary thyroid carcinoma. She presented with acromegaly at age 48 (insulin-like growth factor 1, 556 mcg/L [reference range, 90-360] and lack of growth hormone suppression on glucose tolerance testing) and underwent transsphenoidal resection of a somatotroph microadenoma. Four years after surgery, she developed recurrent growth hormone excess. She was treated with cabergoline, which was discontinued due to intolerance, and transitioned to lanreotide depot, which was switched to pegvisomant because of prediabetes. Her insulin-like growth factor 1 levels remained normal on pegvisomant. Follow-up magnetic resonance imaging examinations showed no evidence of tumor progression. Shortly after the diagnosis of acromegaly, the patient was diagnosed with endometrial carcinoma, bilateral ovarian cystadenomas, and uterine leiomyomas. She was additionally found to have a nonfunctioning adrenal nodule and hyperplastic and adenomatous colon polyps. There are multiple family members with malignancies, including colon, thyroid, and lung cancer. Discussion: This is a novel report of a patient with a pathogenic germline CHEK2 mutation and multiple malignant and benign tumors, including recurrent acromegaly. Conclusion: Our data raise the possibility that CHEK2 mutations may be involved in the development of acromegaly. Additional studies are needed to elucidate the potential role of CHEK2 mutations in the pathogenesis of somatotroph adenomas.

Magnetic resonance imaging of the hypothalamo-pituitary region.

The diagnosis and management of mass lesions in the sellar and parasellar areas remain challenging. When approaching patients with possible sellar or hypothalamic masses, it is important not only to focus on imaging but also detect possible pituitary hormone deficits or excess, in order to establish an appropriate diagnosis and initiate treatment. The imaging modalities used to characterize hypothalamic and pituitary lesions have significantly evolved over the course of the past several years. Computed tomography (CT) and CT angiography play a major role in detecting various sellar lesions, especially in patients who have contraindications to magnetic resonance imaging (MRI) and can also yield important information for surgical planning. However, MRI has become the gold standard for the detection and characterization of hypothalamic and pituitary tumors, infections, cystic, or vascular lesions. Indeed, the imaging characteristics of hypothalamic and sellar lesions can help narrow down the differential diagnosis preoperatively. In addition, MRI can help establish the relationship of mass lesions to surrounding structures. A pituitary MRI examination should be obtained if there is concern for mass effect (including visual loss, ophthalmoplegia, headache) or if there is clinical suspicion and laboratory evidence of either hypopituitarism or pituitary hormone excess. The information obtained from MRI images also provides us with assistance in planning surgery. Using intraoperative MRI can be very helpful in assessing the adequacy of tumor resection. In addition, MRI images yield reliable data that allow for noninvasive monitoring of patients postoperatively.