Treatment of Hypercortisolism

Introduction to Treatment Options

• The Endocrine Society recommends transsphenoidal surgery as the first-line treatment for Cushing's disease, with remission rates varying from 37% to 88% 1
• The American Association of Clinical Endocrinologists suggests that repeat transsphenoidal surgery may be considered for recurrent disease if tumor is evident on MRI, especially if the first surgery was not performed at a specialized center 1

Treatment Based on Source of Hypercortisolism

• For patients with Cushing's disease, the European Society of Endocrinology recommends transsphenoidal surgery, with radiation therapy as an alternative for persistent or recurrent disease, achieving biochemical control in approximately 80% of patients 1
• The American College of Surgeons recommends laparoscopic adrenalectomy for benign adenomas or open adrenalectomy with lymph node removal for suspected carcinomas in patients with adrenal source hypercortisolism 2
• For ectopic ACTH source, the National Comprehensive Cancer Network suggests surgical removal of the ectopic tumor as first-line treatment, with medical therapy or bilateral adrenalectomy as alternatives when surgery is not possible 2

Medical Therapy Options

• The Endocrine Society recommends ketoconazole, osilodrostat, or metyrapone as first-line medical therapy for mild disease with no visible tumor on MRI, with osilodrostat and metyrapone working within hours and ketoconazole working within days 3
• The American Association of Clinical Endocrinologists suggests that cabergoline can be used for mild disease, less effective but requires less frequent dosing, and may be preferred for patients with visible tumor due to potential for tumor shrinkage 3
• The European Society of Endocrinology recommends mifepristone for improving hyperglycemia and weight gain associated with hypercortisolism, but notes that it should only be used by clinicians with extensive experience in Cushing's disease 3

Combination Therapy Approaches

• The National Institute of Health suggests combining ketoconazole with metyrapone to maximize adrenal blockade when monotherapy is ineffective, and monitoring for overlapping toxicities, particularly QTc prolongation 3
• The American Heart Association recommends considering combination therapy with a steroidogenesis inhibitor plus a tumor-targeting agent, such as ketoconazole plus cabergoline, if visible tumor is present 3

Bilateral Adrenalectomy (BLA)

• The Endocrine Society recommends considering BLA when medical therapy fails to control severe hypercortisolism, resulting in immediate control of cortisol excess but requiring lifelong glucocorticoid and mineralocorticoid replacement 3
• The American College of Surgeons notes that BLA provides long-term clinical improvement in BMI, diabetes, hypertension, and muscle weakness in >80% of patients, but requires lifelong monitoring for pituitary hormone deficiencies 2

Monitoring During Treatment

• The European Society of Endocrinology recommends monitoring ACTH levels as significant elevations may indicate tumor growth, and performing MRI 6-12 months after initiating treatment and repeat every few years 4
• The American Association of Clinical Endocrinologists suggests monitoring for adrenal insufficiency due to overtreatment with steroidogenesis inhibitors, and performing baseline ECG and gallbladder ultrasound for pasireotide 1

Pitfalls and Caveats

• The National Comprehensive Cancer Network notes that hypopituitarism is common after radiation therapy, occurring in 25-50% of patients, and generally increases over time 2
• The Endocrine Society warns of the escape phenomenon, which occurs in up to 23% of initially responsive patients on ketoconazole, and notes that preoperative medical therapy may make it difficult to assess surgical remission 1

Medical Management of Recurrent Cushing Disease After Failed Surgeries with Negative MRI

First‑Line Pharmacotherapy

• Osilodrostat is the most effective steroidogenesis inhibitor for normalizing 24‑hour urinary free cortisol (UFC) in patients with recurrent Cushing disease after surgery, based on prospective trial data. The drug is started at 2 mg twice daily and titrated up to the dose that achieves UFC normalization (up to 30 mg twice daily). 5

Monitoring During Medical Therapy

Biochemical Monitoring

• UFC should be measured every 2–4 weeks while titrating the osilodrostat dose to ensure biochemical control. 5
• Morning ACTH levels are checked concurrently; a sustained rise may prompt repeat MRI to evaluate for tumor regrowth, although ACTH’s short half‑life means isolated elevations do not definitively indicate growth. [5][6]

Imaging Surveillance

• A pituitary MRI is performed 6–12 months after initiating medical therapy and then repeated every few years; more frequent imaging is advised if ACTH levels show a progressive increase. [5][6]

Safety Monitoring for Osilodrostat

• Baseline and periodic ECGs are required to monitor QTc interval, given the risk of QTc prolongation with steroidogenesis inhibitors. [5][6]
• Serum electrolytes are monitored for hypokalemia and hypertension secondary to mineralocorticoid‑precursor accumulation. 7

Indications for Re‑operation (Even with Negative MRI)

• Re‑operation may be considered in highly selected patients when an experienced pituitary surgeon at a high‑volume center deems it feasible and when prior pathology showed ACTH‑positive adenoma or a central ACTH gradient on IPSS. 7
• Reported remission rates after repeat surgery range from 37 % to 88 %, with higher success at specialized centers; however, after two prior surgeries, medical therapy is generally preferred unless a new tumor becomes visible. 7

Radiation Therapy as Adjunct

• Conventional pituitary radiation achieves biochemical remission in roughly two‑thirds of patients over several years, making it a viable adjuvant for persistent disease when medical therapy fails. 6
• A major long‑term adverse effect is hypopituitarism, occurring in 25 %–50 % of irradiated patients and increasing over time. 6

Long‑Term Surveillance

• Lifetime follow‑up is required because recurrence can appear up to 15 years after apparent remission.
• Annual late‑night salivary cortisol (LNSC) testing is the most sensitive method for early detection of recurrence and typically becomes abnormal before DST or UFC. 7
• After initial disease control, semi‑annual clinical assessment and UFC measurement are performed for the first 2 years, followed by annual evaluation thereafter.

Critical Pitfalls to Avoid

• Do not label treatment failure based on inadequate dosing; ensure the patient has received the maximum tolerated dose before declaring resistance. 5
• If serial MRIs demonstrate progressive tumor enlargement, pause medical therapy and reassess the management plan, as this may signal aggressive disease. [5][6]
• Avoid performing surveillance hormone tests while the patient is on exogenous glucocorticoids, because these suppress endogenous ACTH and cortisol and render results uninterpretable.

All statements are derived from peer‑reviewed evidence cited in the Lancet Diabetes & Endocrinology (2021).

Cabergoline Use in Recurrent ACTH‑Dependent Cushing Disease – Evidence and Recommendations

Efficacy and Indications

• Cabergoline demonstrates limited biochemical efficacy in Cushing disease and should not be relied upon as primary therapy; it may be considered only as adjunctive treatment for patients with mild residual hypercortisolism while awaiting definitive therapy. 8
• In a prospective pre‑operative study, only 25 % of patients achieved a significant cortisol reduction after 6 weeks of cabergoline, indicating poor overall response. 9
• Current clinical guidelines advise reserving cabergoline for patients with mild Cushing disease because it is less effective and slower‑acting than steroidogenesis inhibitors. 8
• For patients with mild‑to‑moderate disease and a visible residual pituitary tumor, cabergoline may be preferred over other agents due to a potential tumor‑shrinkage effect, although its limited efficacy must be weighed. 8

Preferred First‑Line Medical Therapies

• Osilodrostat or metyrapone should be prioritized as first‑line agents because they normalize cortisol within hours, providing more reliable control than cabergoline. 8
• In the absence of a visible tumor on MRI, ketoconazole, osilodrostat, or metyrapone are the recommended first‑line medical therapies for recurrent disease. 8

Adjunctive Use of Cabergoline

• Cabergoline may be added to steroidogenesis inhibitors when hypercortisolism remains uncontrolled, particularly when a residual tumor is present that could benefit from possible shrinkage. 10

Safety Considerations

• Cabergoline should be avoided in patients with a history of bipolar disorder or impulse‑control disorders because of the risk of dopaminergic‑related psychiatric side effects. 8

Timing of Definitive Therapy

• Prolonged trials of cabergoline must not delay definitive interventions (repeat surgery at an experienced center or radiation therapy), as ongoing hypercortisolism increases morbidity. 9

Role of Radiation and Adrenalectomy

• Stereotactic radiosurgery achieves biochemical control in approximately 80 % of patients, but hypopituitarism occurs in 25‑50 % and tends to increase over time. 9
• Bilateral adrenalectomy is reserved for severe, refractory disease or life‑threatening emergencies when all medical options have failed to control hypercortisolism. 11