General Information About Pituitary Tumors
Pituitary tumors represent from 10% to 25% of all intracranial neoplasms. Depending on the study cited, pituitary tumors can be classified into three groups according to their biological behavior:[1,2]
- Benign adenoma.
- Invasive adenoma.
- Carcinoma.
Adenomas comprise the largest portion of pituitary neoplasms with an overall estimated prevalence of approximately 17%. Only a minority of adenomas are symptomatic.[3] In addition, pituitary adenomas may be distinguished anatomically as intrapituitary, intrasellar, diffuse, and invasive.[4] Invasive adenomas, which account for approximately 35% of all pituitary neoplasms, may invade the dura mater, cranial bone, or sphenoid sinus.[5] Carcinomas account for 0.1% to 0.2% of all pituitary tumors.[6,7]
Clinical Presentation
The most characteristic-presenting features of pituitary adenomas include inappropriate pituitary hormone secretion and visual field deficits.[8]
Rare signs and symptoms of pituitary disease include:[8]
- Cranial nerve palsies.
- Temporal lobe epilepsy.
- Hydrocephalus.
- Cerebrospinal fluid rhinorrhea.
The signs and symptoms commonly associated with pituitary tumors derived from each specific cell type (i.e., prolactinomas, corticotroph adenomas, somatotroph adenomas, thyrotroph adenomas, and nonfunctioning adenomas) are as follows:
Prolactin-producing pituitary tumors
Signs and symptoms of prolactin (PRL)-producing pituitary tumors, also known as prolactinomas and lactotroph adenomas, may include:[8]
- Headache. (Refer to the PDQ summary on Cancer Pain for more information.)
- Visual field deficits.
- Oligomenorrhea or amenorrhea.
- Reduced fertility.
- Loss of libido.
- Erectile dysfunction.
- Galactorrhea in the estrogen-primed female breast.
Adrenocorticotrophic hormone-producing pituitary tumors
Signs and symptoms of adrenocorticotrophic hormone (ACTH)-producing pituitary tumors, also known as corticotroph adenomas, may include:[8]
- Headache. (Refer to the PDQ summary on Cancer Pain for more information.)
- Visual field deficits.
- Proximal myopathy.
- Centripetal fat distribution.
- Neuropsychiatric symptoms. (Refer to the PDQ summary on Adjustment to Cancer: Anxiety and Distress and the Symptoms and Risk Factors section in the Assessment and Diagnosis section of the PDQ summary on Depression for more information.)
- Striae.
- Ability to easily bruise.
- Skin thinning.
- Hirsutism.
- Osteopenia.
Growth hormone-producing pituitary tumors
Signs and symptoms of growth hormone (GH)-producing pituitary tumors, also known as somatotroph adenomas, may include:[8]
- Headache. (Refer to the PDQ summary on Cancer Pain for more information.)
- Visual field deficits.
- Growth of hands and feet.
- Coarsening of facial features.
- Carpal tunnel syndrome.
- Snoring and obstructive sleep apnea. (Refer to the Assessment section and the Special Considerations section in the PDQ summary on Sleep Disorders for more information.)
- Jaw growth and prognathism.
- Osteoarthritis and arthralgia. (Refer to the PDQ summary on Cancer Pain for more information.)
- Excessive sweating. (Refer to the PDQ summary on Hot Flashes and Night Sweats for more information.)
- Dysmorphophobia.
Thyrotropin-producing pituitary tumors
Signs and symptoms of thyrotropin (thyroid-stimulating hormone [TSH])-producing tumors, also known as thyrotroph adenomas, may include:[9]
- Palpitations.
- Tremor.
- Weight loss. (Refer to the PDQ summary on Nutrition in Cancer Care for more information.)
- Insomnia. (Refer to the PDQ summary on Sleep Disorders for more information.)
- Hyperdefecation.
- Sweating. (Refer to the PDQ summary on Hot Flashes and Night Sweats for more information.)
Nonfunctioning adenomas
Signs and symptoms of nonfunctioning adenomas (most commonly gonadotroph adenomas) may include:[10]
- Headache. (Refer to the PDQ summary on Cancer Pain for more information.)
- Visual field deficits.
- Pituitary insufficiency, which is due to compression of the pituitary stalk or destruction of normal pituitary tissue by the tumor, and predominantly manifests as secondary hypogonadism.
- Rarely, ovarian overstimulation, testicular enlargement, or increased testosterone levels.
In addition to cell-type specific presentations, pituitary apoplexy (i.e., pituitary adenoma apoplexy) represents another important clinical presentation of pituitary adenomas. Pituitary apoplexy can result from an acute hemorrhagic or ischemic infarction of the pituitary in patients harboring often unrecognized secreting or nonfunctioning pituitary adenomas. In a series analyzing 40 cases of pituitary apoplexy, the presenting signs and symptoms included headache (63%), vomiting (50%), visual field defects (61%), ocular paresis (40%), mental deterioration (13%), hyponatremia (13%), and syncope (5%); in only four cases pituitary tumor was diagnosed prior to presentation.[11]
The development of pituitary adenomas may also occur as a component of three familial cancer syndromes:[8]
- Multiple endocrine neoplasia 1 (MEN 1).
- Carney complex (e.g., cardiac myxomas, spotty skin pigmentation, and tumors of the adrenal gland and anterior pituitary).
- Isolated familial acromegaly.
A number of other lesions should be considered in the differential diagnosis of sellar masses. Although rare, lymphocytic (i.e., autoimmune) hypophysitis should be considered in the differential diagnosis of any nonsecreting pituitary mass, especially when occurring during pregnancy or postpartum.[12] In addition, the clinician should consider craniopharyngioma and Rathke cleft cyst in the differential diagnosis of pituitary tumors. Sellar masses may also result from tumors that are metastatic to the pituitary. This typically occurs as a part of a generalized metastatic spread and is usually associated with five or more additional metastatic sites, especially osseous; breast and lung cancer are the most common primary neoplasms metastasizing to the pituitary.[13]
References
- Asa SL, Ezzat S: The cytogenesis and pathogenesis of pituitary adenomas. Endocr Rev 19 (6): 798-827, 1998. [PUBMED Abstract]
- Landman RE, Horwith M, Peterson RE, et al.: Long-term survival with ACTH-secreting carcinoma of the pituitary: a case report and review of the literature. J Clin Endocrinol Metab 87 (7): 3084-9, 2002. [PUBMED Abstract]
- Ezzat S, Asa SL, Couldwell WT, et al.: The prevalence of pituitary adenomas: a systematic review. Cancer 101 (3): 613-9, 2004. [PUBMED Abstract]
- Kovacs K, Horvath E, Vidal S: Classification of pituitary adenomas. J Neurooncol 54 (2): 121-7, 2001. [PUBMED Abstract]
- Scheithauer BW, Kovacs KT, Laws ER Jr, et al.: Pathology of invasive pituitary tumors with special reference to functional classification. J Neurosurg 65 (6): 733-44, 1986. [PUBMED Abstract]
- Pernicone PJ, Scheithauer BW, Sebo TJ, et al.: Pituitary carcinoma: a clinicopathologic study of 15 cases. Cancer 79 (4): 804-12, 1997. [PUBMED Abstract]
- Ragel BT, Couldwell WT: Pituitary carcinoma: a review of the literature. Neurosurg Focus 16 (4): E7, 2004. [PUBMED Abstract]
- Levy A: Pituitary disease: presentation, diagnosis, and management. J Neurol Neurosurg Psychiatry 75 (Suppl 3): iii47-52, 2004. [PUBMED Abstract]
- Vance ML: Treatment of patients with a pituitary adenoma: one clinician’s experience. Neurosurg Focus 16 (4): E1, 2004. [PUBMED Abstract]
- Losa M, Mortini P, Barzaghi R, et al.: Endocrine inactive and gonadotroph adenomas: diagnosis and management. J Neurooncol 54 (2): 167-77, 2001. [PUBMED Abstract]
- Lubina A, Olchovsky D, Berezin M, et al.: Management of pituitary apoplexy: clinical experience with 40 patients. Acta Neurochir (Wien) 147 (2): 151-7; discussion 157, 2005. [PUBMED Abstract]
- Caturegli P, Newschaffer C, Olivi A, et al.: Autoimmune hypophysitis. Endocr Rev 26 (5): 599-614, 2005. [PUBMED Abstract]
- Komninos J, Vlassopoulou V, Protopapa D, et al.: Tumors metastatic to the pituitary gland: case report and literature review. J Clin Endocrinol Metab 89 (2): 574-80, 2004. [PUBMED Abstract]
