Pituitary Tumors

LSUHSC New Orleans Department of Neurosurgery

Pituitary Tumors

Jerome M. Volk III, HO VLSU Department of Neurosurgery


Anatomy

• The pituitary gland weighs 0.6 g.• It is composed of an anterior

adenohypophysial component in apposition with a morphologically, embryologically, and functionally distinct posterior neurohypophysial component.


Anatomy


Anatomy



Embryology

• Entirely ectodermal in origin– Adenohypophysis

• Develops from Rathke’s pouch

• Upward invagination

– Neurohypophysis• Develops from the

infundibulum• Downward extension of

the floor of the diencephalon


Endocrinology

• Anterior portion (Adenohypophysis)– Follicle stimulating hormone (FSH)– Leutinizing hormone (LH)– Adrenocorticotrophic hormone (ACTH)– Thyroid stimulating hormone (TSH)– Prolactin– Growth hormone (GH)


Hormone Signs and symptoms of hypersecretion

Signs and symptoms of hyposecretion

Lab Values

FSH, LH Clinically silent Mood swings, impotence, vaginal dryness, hot flashes, osteoporosis, decreased libido

LH, FSH, Serum testosterone, Serum estradiol

ACTH Cushing’s disease-moon facies, buffalo hump, puple striae, hypertension

Weight loss, nausia, hyponatremia and hypoglycemia, hypotension, fatigue

Serum cortisol

TSH Goiter, moist skin, tachycardia, palpitations, insomnia

Weight gain, fatigue, constipation, cold intolerance, bradycardia

TSH, free T4


Hormone Signs and symptoms of hypersecretion

Signs and symptoms of hyposecretion

Lab Values

Prolactin Menstrual irregularites, infertility, galactorrhea, weight gain

Silent Prolactin

GH Acromegaly-overgrowth, carpal tunnel, hyperhidrosis

Dwarfism, fatigue, osteoporosis, weight gain

IGF-1, GH


Endocrinology

• Posterior gland (Neurohypophysis)– Oxytocin• Uterine contractions and lactation

– Anti-diuretic hormone• SIADH-increased water resorption, low sodium• DI-increased urination, high sodium


Epidemiology

• Pituitary tumors account for 10-15% of all primary brain tumors

• Highest incidence between the 3rd and 6th decade

• More common in women• Genetic predisposition seen only in MEN-1.– Although this accounts for only 3% of pituitary

tumors


• Sellar masses:– Tumors

• Adenohypophysial origin– Pituitary adenoma (macro and micro)– Pituitary carcinoma

• Neurohypophysial origin– Granular cell tumor

• Nonpituitary origin– Meningioma– Glioma– Craniopharyngioma– Germ cell tumor


• Sellar masses:– Cysts and Hamartomas: Epidermoid, arachnoid,

rathke cleft, dermoid, hypothalamic hamartoma– Metastatic: carcinoma, lymphoma– Infammatory: sarcoidosis, langerhans cell

histiocytosis, lymphocytic hypophysitis– Vascular: aneurysm, cavernoma


Pituitary Adenoma

• Classified by:– Endocrine/Clinical– Pathology– Imaging


Pituitary Adenoma

• Prolactinoma:– 30% of pituitary adenomas• More commonly micradenomas

– Present as amenorrhea with galactorrhea– Prolactin levels > 200 ng/ml (if less worry about

stalk effect)– First line treatment is pharmacologic• Dopamine agonists (bromocriptine


• Growth Hormone Secreting Tumor– Most commonly macroadenoma– Occur in the 4th and 5th decade– Coarse facial features, thickening of lips,

enlargement of nose– GH level > 5 ng/ml– Initial treatment is surgery


• Corticotroph Secreting Adenomas– 8-10% of pituitary tumors– Cushing’s Disease

• Hypercortisolemic state generated in response to an ACTH-secreting pituitary tumor.

• Weight gain, truncal obesity, buffalo hump• Free cortisol level

– no cortisol suppression on low-dose dexamethasone testing, cortisol suppression on high-dose dexamethasone testing, and moderately elevated ACTH levels

• Surgery is best option


• Thyrotroph adenomas– Less than 1% of pituitary adenomas– Manifest with signs of hyperthyroidism– High TSH with high Free T4– Surgery is first option

• Clinically silent– 1/4th of pituitary tumors– Surgery is first option


• Presenting signs and symptoms:– Pituitary hyperfunction– Pituitary insufficiency– Mass effect• Headache-pressure on V1 at diagphragma sella• Loss of vision-compression of optic chiasm• Hydrocephalus-compression on third ventricle• Hypothalamic abnormality-sleep, alertness, emotion



• Labs and images– Imaging:• MRI brain with and without IV contrast (include thing

cuts through pituitary)– Tumor enhances less than gland

– Labs:• Prolactin, FSH, LH, GH, ACTH, testosterone, GH,

cortisol, IGF-1

– Visual Fields:• To be performed by an ophthomalogist


Visual Fields


9 months later


MRI


MRI


• Surgical indications:– Progressive mass effect• Worsening of vision

– Failure of prior treatment• Pharmacologic

– Prolactinoma– Cushing’s disease

• Radiation


• Surgical indications:– Pituitary Apoplexy• The abrupt and occasionally catastrophic acute

hemorrhagic infarction of a pituitary adenoma• Present with acute headache, meningismus, visual

impairment, ophthalmoplegia, and alteration in consciousness• Glucocorticoid replacement is the most important first

step due to adrenal insufficiency– Followed by urgent surgical decompression


Pituitary Apoplexy


• Surgical Approaches:– Transsphenoidal• Endoscopic• Endonasal• Sublabial transseptal

– Transcranial• Pterional• Subfrontal


Transsphenoidal


Transsphenoidal

Endonasal Sublabial


Transsphenoidal


Transsphenoidal


Transsphenoidal


Transcranial


Transcranial


Transcranial


Transcranial


Transcranial


• Post-operative Complications:– Diabetes Insipidus• Follow urine output and Sodium levels

– CSF leak• Check for rhinorrhea

– Hemorrhage/Apoplexy• Worsening vision


Thank you

Documents

Pituitary Tumors