Hypophysitis

Silent hypothysitis

Asymptomatic or mild, no headache

Management escalation pathway

Await pituitary axis to confirm diagnosis, but warn patients to seek urgent review if he-she is feeling unwell
Continue ICPi with appropriate HRT
Discuss with endocrinologist

Hypophysitis with headache not mentioned in CTCAE (part of endocrine disorders – other)

Headache (usually severe and not responding to conventional treatments) limiting age appropriate ADL.
Hospitalization or prolongation of hospitalization

Withhold ICPi

Oral prednisolone 0.5-1 mg/kg 1x/day aer sending pituitary axis assessment
If no improvement within 48h, treat with i.v. (methyl)prednisolone if signs of adrenal crisis, manage per standard guidelines
Initial replacement advice for cortisol and thyroxine: 1) If 9 am cortisol < 250 or random cortisol < 150 and vague symptoms: Replace with hydrocortisone: 20/10/10 mg If thyroid function tests normal: 1–2 weekly monitoring initially (always replace cortisol for 1 week prior to thyroxine initiation) 2) If low FT4: Consider need for thyroxine replacement (guide is 0.5-1.5 µg/kg) based on symptoms +/- check 9 am weekly cortisol See Thyroid Guidelines for further information regarding interpretation of an abnormal TSH/T4
Longterm Wean steroids based on symptoms over 2-4 weeks to 5 mg prednisolone
Refer to or consult endocrinologist
Monitor thyroid function tests (TFTs)

Assessment and Investigations

ENDOCRINE LAB measurements:

• 9 am cortisol (or random if unwell and treatment cannot be delayed) + CBG (to exclude CBG-deficiency)
• Oestradiol if premenopausal
• Testosterone in men + SHBG +/- albumin for evaluation of free testosterone
• IGF-1 (cave: long T1/2: acute GH-deficiency might me missed)
• Blood glucose level imaging
• MRI hypophysis (hypophysitis is typically associated with swollen hypophysis)
• + include whole brain imaging to exclude metastases to the brain and/or leptomeninges