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Anterior Pituitary Masses and Hyperprolactinemia. Thomas Repas DO FACP CDE UW Hospital and Clinics Department of Medicine Section of Endocrinology, Diabetes & Metabolism H4/568 CSC (5148), 600 Highland Avenue, Madison, WI 53792 Thursday October 13, 2005. Objectives.
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Anterior Pituitary Masses and Hyperprolactinemia Thomas Repas DO FACP CDE UW Hospital and Clinics Department of Medicine Section of Endocrinology, Diabetes & Metabolism H4/568 CSC (5148), 600 Highland Avenue, Madison, WI 53792 Thursday October 13, 2005
Objectives • Causes of Pituitary Masses • Evaluation of a Pituitary Incidentaloma • Management of Pituitary Neoplasia • Abnormal Anterior Pituitary Function Associated with Pituitary Masses • Hyperprolactinemia and Prolactinomas • Causes • Management
I will not discuss in detail… • Management of Cushing’s Disease • Management of Acromegaly • Management of Hypopituitarism • Evaluation and Management of Posterior Pituitary Disorders and Diabetes Insipidus
Normal Pituitary Anatomy Lechan RM. Neuroendocrinology of Pituitary Hormone Regulation. Endocrinology and Metabolism Clinics 16:475-501, 1987
Normal Pituitary Anatomy Modified from Lechan RM. Neuroendocrinology of Pituitary Hormone Regulation. Endocrinology and Metabolism Clinics 16:475-501, 1987
Development of Human Anterior Pituitary Cohen and Radovick, Endocrine Reviews 23: 431-442, 2002
Anterior Pituitary Function Adapted from: William’s Textbook of Endocrinology, 10th ed., Figure 8-4, pg 180.
Etiology of Pituitary-Hypothalamic Lesions • Non-Functioning Pituitary Adenomas • Endocrine active pituitary adenomas • Prolactinoma • Somatotropinoma • Corticotropinoma • Thyrotropinoma • Other mixed endocrine active adenomas • Malignant pituitary tumors:Functional and non-functional pituitary carcinoma • Metastases in the pituitary (breast, lung, stomach, kidney) • Pituitary cysts:Rathke's cleft cyst, Mucocoeles, Others • Empty sella syndrome
Etiology of Pituitary-Hypothalamic Lesions (continued) • Developmental abnormalities:Craniopharyngioma (occasionally intrasellar location), Germinoma, Others • Primary Tumors of the central nervous system: Perisellar meningioma, Optic glioma, Others • Vascular tumors:Hemangioblastoma, Others • Malignant systemic diseases:Hodgkin's disease, Non-Hodgkin lymphoma, Leukemic infiltration, Histiocystosis X, Eosinophilic granuloma, Giant cell granuloma (tumor) • Granulomatous diseases: Neurosarcoidosis, Wegner's granulomatosis, Tuberculosis, Syphilis • Vascular aneurysms (intrasellar location)
Sellar Masses Pituitary Adenoma Craniopharyngioma Snyder, P. UpToDate
Sellar Masses Lymphocytic Hypophysitis Pituitary Adenoma Snyder, P. UpToDate
Infiltrative Disorders: Sarcoidosis From EndoText: http://www.endotext.com/neuroendo/neuroendo4/neuroendoframe4.htm
Evaluation of an Incidental Pituitary Mass • Radiologic Evaluation • Clinical Evaluation • Hormonal Evaluation
Radiologic Evaluation: MRI • Preferred imaging study for the pituitary • Better visualization of soft tissues and vascular structures than CT • No exposure to ionizing radiation • Images are generated based upon the magnetic properties of the hydrogen atoms • T1-weighted images produce high–signal intensity images of fat. Structures such as fatty marrow and orbital fat show up as bright images. • T2-weighted images produce high-intensity signals of structures with high water content, such as cerebrospinal fluid and cystic lesions Mulinda, J. Pituitary Macroadenomas, 9/19/05. http://www.emedicine.com/med/topic1379.htm
Radiologic Evaluation: CT • Better at visualizing bony structures and calcifications within soft tissues • Better at determining diagnosis of tumors with calcification, such as germinomas, craniopharyngiomas, and meningiomas • May be useful when MRI is contraindicated, such as in patients with pacemakers or metallic implants in the brain or eyes • Disadvantages include: • less optimal soft tissue imaging compared to MRI • use of intravenous contrast media • exposure to radiation Mulinda, J. Pituitary Macroadenomas, 9/19/05. http://www.emedicine.com/med/topic1379.htm
Craniopharyngioma on CT Kruskal, J. UpToDate
Clinical Evaluation • All patients with macroadenomas should have formal visual field testing • In addition to radiographic and hormonal evaluation, patients should be asked and examined for any clinical signs suspicious for pituitary hyperfunction or hypofunction
Hormonal Evaluation • Mayinclude of both basal hormone measurement and dynamic stimulation testing. • All pituitary masses should have screening basal hormone measurements, including: • Prolactin • TSH, FT4 • ACTH, AM cortisol, midnight salivary cortisol • LH, FSH, estradiol or testosterone • Insulin-like growth factor-1 (IGF-1) Mulinda, J. Pituitary Macroadenomas, 9/19/05. http://www.emedicine.com/med/topic1379.htm
Hormonal Evaluation (continued) Dynamic stimulation/suppression testing may be useful in select cases to further evaluate pituitary reserve and/or for pituitary hyperfunction • Dexamethasone suppression testing • Oral glucose GH suppression test • GHRH, L-dopa, arginine • CRH stimulation • Metyrapone • TRH stimulation • GnRH stimulation • Insulin-induced hypoglycemia Mulinda, J. Pituitary Macroadenomas, 9/19/05. http://www.emedicine.com/med/topic1379.htm
Management of Pituitary Neoplasia • Observation • Pharmacotherapy • Surgery • Radiation Therapy
Pituitary Incidentaloma < 10 mm > 10 mm • Evaluate for: • Hormonal Hypersecretion • Hormonal Hyposecretion • Visual Changes/defects Evaluate for Hormonal Hypersecretion Hormonal or Visual Abnormalities Normal No Abnormalities Observe Treatment Observe
Observation and Follow-up • If less than 20 mm and no neurologic or hormonal abnormalities: • Monitor for adenoma size, visual changes, and hormonal hypersecretion in 6 and 12 months, then annually for a few years • Lesions less than 10 mm and proven to have no hormonal hypersecretion: • Lesions 2 to 4 mm: no further testing required • Lesions 5 to 9 mm: MRI can be done once or twice over the subsequent two years; if the lesion is stable in this period, the frequency can be decreased Peter J Snyder MD, “Pituitary incidentaloma” UpToDate November 25, 2003
Pharmacotherapy • Most useful in prolactinomas, alone or with other intervention. • May be used in certain other functioning tumors as adjunctive therapy along with surgical and/or radiotherapy
Pharmacotherapy Which pharmacologic option to choose depends on type of tumor: • Dopamine agonists:bromocriptine, cabergoline- most useful for prolactinomas, less useful for GH secreting adenomas • Somatostatin analog (Octreotide, Octreotide LAR)-most useful for acromegaly • Pegvisomant (GH receptor blocker)-useful in acromegaly refractory to somatostatin analogues • Other: ketoconazole, metyrapone, mitotane-for Cushings disease- use limited by side effects, expense and lack of efficacy
Pituitary Surgery • Transsphenoidal approach: used for 95% of pituitary tumors • Endonasal submucosal transseptal approach • Septal Pushover/Direct Sphenoidotomy • Endoscopic approach
Indications for Surgery • Surgery is the first-line treatment of symptomatic pituitary adenomas. • Useful when medical or radiotherapy fails • Surgery provides prompt relief from excess hormone secretion and mass effect. • Indicated in pituitary apoplexy with compressive symptoms
Outcome of Transsphenoidal Surgery John A. Jane, Jr., MD Edward R. Laws, Jr., MD,SURGICAL MANAGEMENT OF PITUITARY ADENOMASChapter 13. http://www.endotext.com/neuroendo/neuroendo13/neuroendoframe13.htm
Complications of Transsphenoidal Surgery John A. Jane, Jr., MD Edward R. Laws, Jr., MD,SURGICAL MANAGEMENT OF PITUITARY ADENOMASChapter 13. http://www.endotext.com/neuroendo/neuroendo13/neuroendoframe13.htm
Radiation Therapy • Reserved for patients with larger tumors and/or persistent hormonal hyperfunction despite surgical intervention • Conventional radiotherapy • Gamma knife radiosurgery
Conventional Radiotherapy • Response is slow, may take 5 to 10 years for full effect • Successful in up to 80% of acromegalics and 55-60% of Cushing’s disease • High rate of hypopituitarism: up to 60% • Other complications: optic nerve damage, seizures, radionecrosis of brain tissue Basic and Clinical Endocrinology, 6th ed. Chapter 5 Hypothalamus and Pituitary, 100-162.
Gamma Knife Radiosurgery • Stereotactic CT guided cobalt 60 gamma radiation to narrowly focused area • Long term data not yet available but suggest up to a 70% response rate for acromegaly and up to 70% for Cushing’s in some centers • Complication rate likely lower, but still high rate of hypopituitarism (~55%) Basic and Clinical Endocrinology, 6th ed. Chapter 5 Hypothalamus and Pituitary, 100-162.
Abnormal Pituitary Function Associated with Pituitary Tumors
Disorders of Pituitary Function • Hypopituitarism • Central hypoadrenalism, hypogonadism, hypothyroidism or GH deficiency • Panhypopituitarism • Hypersecretion of Pituitary Hormones • Hyperprolactinemia • Acromegaly • Cushing’s Disease
Acromegaly http://www.endotext.com/neuroendo/neuroendo5e/neuroendoframe5e.htm
Clinical Findings of Acromegaly http://www.endotext.com/neuroendo/neuroendo5e/neuroendoframe5e.htm
Complications of Acromegaly • Neurologic • Carpal Tunnel syndrome • Stroke • Neoplastic • Colorectal • (Breast and prostate - uncertain) • Musculoskeletal • Degenerative arthropathy • Calcific discopathy, pyrophosphate arthropathy Cardiovascular • Ischemic heart disease • Cardiomyopathy • Congestive heart failure • Arrhythmias • Hypertension Respiratory • Kyphosis • Obstructive sleep apnea Metabolic • Diabetes mellitus/IGT • Hyperlipidemia http://www.endotext.com/neuroendo/neuroendo5e/neuroendoframe5e.htm
Acromegaly: Causes of Death • Cardiovascular- 38 to 62 percent • Respiratory- 0 to 25 percent • Malignancy- 9 to 25 percent
Diagnosis of Acromegaly • Random GH – not useful • Insulin like growth factor 1 (IGF-1) – best for screening • Oral glucose GH suppression testing – gold standard to confirm diagnosis
Cushing’s Disease William’s Textbook of Endocrinology. 8th Ed. Foster, DW, Wilson, JD (Eds), WB Saunders, Philadelphia, 1996
Cushing’s Syndrome vs. Cushing’s Disease • Cushing’s syndrome is a syndrome due to excess cortisol from pituitary, adrenal or other sources (exogenous glucocorticoids, ectopic ACTH, etc.) • Cushing’s disease is hypercortisolism due to excess pituitary secretion of ACTH (about 70% of cases of endogenous Cushing’s syndrome)
Cushing’s Syndrome • Proximal muscle weakness • Easy bruising • Hirsutism • Hypertension • Osteopenia • Diabetes mellitus/IGT • Impaired immune function/poor wound healing • Moon facies • Facial plethora • Supraclavicular fat pads • Buffalo hump • Truncal obesity • Weight gain • Purple striae
Central Obesity in Cushing’s Disease William’s Textbook of Endocrinology. 8th Ed. Foster, DW, Wilson, JD (Eds), WB Saunders, Philadelphia, 1996
Progressive Obesity of Cushing’s Disease Age 6 Age 7 Age 8 Age 9 Age 11 William’s Textbook of Endocrinology. 8th Ed. Foster, DW, Wilson, JD (Eds), WB Saunders, Philadelphia, 1996
Buffalo Hump in Cushing’s Disease Orth, D. UpToDate