Pituitary

Question 1

What is the pituitary imaging finding in histiocytosis?

Answer 1

an enhancing posterior sellar mass

Question 2

treatment for very aggressive prolactinoma/pituitary carcinoma refractory to cabergoline/bromocriptine, surgery, and stereotactic radiosurgery?

Answer 2

temozolomide

Question 3

common cancers causing pituitary mets

Answer 3

breast, renal cell, lung;
when the pituitary mass is fast growing, think of mets

Question 4

1. What are symptoms of GH deficiency?
2. How to diagnose?
3. cutoff value to diagnose GHD?

Answer 4

1. change in body composition (increase in abdominal girth, change in well-being with fatigue and worsening cognitive function including short-term memory), lower bone density, and cardiovascular risk.
2. glucagon-stimulation test
3. Endo Society Guidelines: <1 ng/ml; Acromegaly consensus group: <0.4 ng/ml

Question 5

1. somatostatin analogs (octreotide, lanreotide, and pasireotide) decrease?
2. which of these worsen glucose tolerance?

Answer 5

1. GH and IGF-1; therefore improve insulin resistance.
2. PASIREOTIDE (decreases GLP-1 and glucose insulinotropic peptide)

Question 6

True or False: oral contraceptive use is safe in women with microadenomas and there is minimal risk of tumor enlargement

Answer 6

TRUE

Question 7

1. True or False: More than 2/3 of children with idiopathic isolated GH deficiency diagnosed by conventional criteria have normal GH secretion as adults
2. Before continuing GH treatment in these patients, what should be done?

Answer 7

1. TRUE
2. GH-stimulation test one month after stopping GH. If GH deficiency is documented to still be present, resume GH treatment at a lower dosage than that used in childhood

Question 8

Pregnant woman with a sellar mass. MRI shows contrast enhancement. Dx?

Answer 8

lymphocytic hypophysitis

Question 9

Patient with history of cancer and/or histiocytosis:
1. MRI findings?
2. associated clinical finding?

Answer 9

1. hypOenhancing mass
2. diabetes insipidus

Question 10

pituitary adenomas:
1. typical MRI feature?

Answer 10

1. hypOenhancing
   rarely associted with diabetes insipidus

Question 11

cystic lesion on pituitary MRI. Ddx?

Answer 11

Rathke cyst

Question 12

mifepristone:
1. MOA?
2. used in the treatment of?
3. what is NOT recommended measurements to be used for dosage adjustment during mifepristone treatment? How should dosage be adjusted?

Answer 12

1. a glucocorticoid receptor blocker. Therefore, cortisol and ACTH levels may actually rise during treatment
2. all forms of Cushing syndrome
3. cortisol and ACTH.
   The dosage should be adjusted solely based on clinical parameters of the activity of Cushing syndrome while avoiding symptoms of adrenal insufficiency

Question 13

Tx of acromegaly:
1. how often is lanreotide given?
2. for pegvisomant to be considered as first-line therapy, how often is administration?

Answer 13

1. monthly
2. daily; this has the highest likelihood of normalizing IGF-1 levels and improving symptoms

Question 14

Women on oral estrogen require what change in GH replacement to normalize serum IGF-1 compared to women on transdermal estrogen or no estrogen?

Answer 14

A 2-3 times higher GH replacement.

Therefore, if a woman switches from oral to transdermal estrogen, GH dose should be decreased to one-half or one-third of the original dosage.

Question 15

What is one of the absolute contraindications to GH therapy?

Answer 15

an active malignancy

Question 16

1. What is the gold standard for assessing GH reserve? What is the caveat?

Answer 16

1. an insulin tolerance test. HOWEVER, caution in a patient with a history of cranial surgery because of concerns regarding possible seizure induction by hypoglycemia.
   –> An alternative test is a GLUCAGON-STIMULATION TEST

Question 17

DDx for: acute onset hypopituitarism in adolescence or young adulthood

Answer 17

craniopharyngioma –> calcification within the lesion
OR
germinoma (germ-cell tumors) –> co-occurrence of suprasellar and pineal lesions