Patients may present with diverse complaints that significantly depend on which pituitary cells are affected and whether the tumor is secreting or not. Smaller, nonsecreting adenomas may be asymptomatic, but the majority of patients report at least one or two symptoms. A headache is rather common, while visual complaints are often present in larger tumors due to compression of the optic chiasm. Bitemporal hemianopsia is highly specific for a pituitary neoplasm, while decreased visual acuity and abnormal pupillary light reflex may be noted as well. Tumor-dependent symptoms seen in pituitary adenomas include:

• Amenorrhea, galactorrhea, gynecomastia, and infertility in the case of prolactinoma.
• Acromegaly, gigantism, carpal tunnel syndrome and voice changes in GH-secreting adenomas.
• Features of Cushing's disease, such as central obesity, moon facies, hypertension and development of a "buffalo hump", may be seen in ACTH-secreting tumors.

In larger tumors, increased production of more than one hormone may be seen [11]. On the other hand, craniopharyngiomas are often accompanied by some form of hormone insufficiency. In approximately 80% of cases, hormonal dysfunction is encountered, most commonly GH, FSH, and LH, but a deficiency of any pituitary hormone may occur [3].

• Weight Gain

  Low TSH causes fatigue, low energy, sensitivity to cold temperatures, constipation, and weight gain. Prolactin. Too little prolactin causes an inability to breastfeed after a woman gives birth to a baby. ACTH. [cancer.net]

  Cushing disease [6, 10] Weight gain, centripetal obesity, moon facies, violet striae, easy bruisability, proximal myopathy, and psychiatric changes Other possible effects - Arterial hypertension, diabetes, cataracts, glaucoma, and osteoporosis [emedicine.medscape.com]

  Depending on which hormones are affected, symptoms might include: Nausea Weakness Unexplained weight loss or weight gain Loss of body hair Feeling cold Feeling tired or weak Menstrual changes or loss of menstrual periods in women Erectile dysfunction [cancer.org]

  gain skin striae (lines/wrinkles/stretch marks) decreased fertility in men mood swings excess hair growth osteoporosis rib and vertebral compression fractures Thyrotropin (TSH) secreting adenomas: weight loss increased appetite heart palpitations or [pituitary.mgh.harvard.edu]

  Cushing's disease symptoms include central weight gain, high blood pressure, high glucose levels, easy bruising, muscle loss (wasting), bone loss, depression, mood swings and abnormal stretch marks. [uwhealth.org]

• Galactorrhea

  Symptoms include a headache and bitemporal hemianopsia in larger tumors, while hormone-induced effects such as acromegaly, galactorrhea, and Cushing's disease may be observed. [symptoma.com]

  Galactorrhea (abnormal breast discharge) Sometimes a woman's breast makes milk even though she is not breast feeding a baby. This is called galactorrhea. The milk may come from one or both breasts. [my.clevelandclinic.org]

  and infertility Men - Decreased libido, impotence, and rarely galactorrhea Growth hormone Children and adolescents - May result in pituitary gigantism Adults - Acromegaly Changes in the size of the hand and feet, coarseness of the face, frontal bossing [emedicine.medscape.com]

  Secretory adenomas may cause diabetes insipidus, galactorrhea, Cushing syndrome, or gigantism or acromegaly. [msdmanuals.com]

• Falling

  Symptoms of hyperthyroidism may include: fast heart rate unintended weight loss tremor increased appetite feelings of being warm or hot, or not tolerating cold trouble falling asleep feeling anxious frequent bowel movements a lump in the front of the [urmc.rochester.edu]

  This can cause symptoms of hyperthyroidism (overactive thyroid), such as: Rapid or irregular heartbeat Tremors (shaking) Weight loss Increased appetite Feeling warm or hot Sweating Trouble falling asleep Anxiety Frequent bowel movements A lump in the [cancer.org]

  About pituitary tumors Pituitary tumors fall under the category of endocrine and neuroendocrine cancer. [scripps.org]

  Because of increased thyroxine turnover and volume of distribution in pregnancy, T4 levels usually fall and TSH levels rise with a fixed thyroxine dose over the course of gestation. [clinicaladvisor.com]

• Easy Bruising

  It can also cause high blood pressure, high blood sugar, brittle bones, emotional changes, stretch marks on the skin, and easy bruising. Gonadotropins (FSH and LH). [cancer.net]

  Cushing's disease symptoms include central weight gain, high blood pressure, high glucose levels, easy bruising, muscle loss (wasting), bone loss, depression, mood swings and abnormal stretch marks. [uwhealth.org]

  bruising Growth of fine hair on the face, upper back or arms Bones that break easily Anxiety, irritability and depression Too much growth hormone may cause: Headache Some loss of vision In adults, acromegaly (growth of the bones in the face, hands and [cancer.osu.edu]

  Too much cortisol can lead to Cushing’s syndrome, with symptoms like: Easy bruising High blood pressure High blood sugar Purple or pink stretch marks Very round face Weak muscles Weight gain in the face, neck, and torso, but thin arms and legs Growth [webmd.com]

  Patients with Cushing’s disease experience symptoms such as weight gain (especially upper body obesity, a round face, and increased fat around the neck); easy bruising; purple or pink stretch marks over the abdomen, thighs, buttocks, arms and breasts; [neurosurgery.wustl.edu]

• Nausea

  Symptoms of pituitary tumors include Headaches Vision problems Nausea and vomiting Problems caused by the production of too many hormones Pituitary tumors are usually curable. Treatment is often surgery to remove the tumor. [medlineplus.gov]

  Nonfunctioning adenomas may cause headaches, nausea, vomiting, and, when they push against the optic chiasm, visual deficits. Diagnosis As with most brain tumors, imaging studies are essential in the diagnosis of pituitary and parasellar tumors. [columbianeurosurgery.org]

  […] menstrual disorders cold intolerance excessive perspiration (sweating) decreased appetite vision impairment, blurriness, blindness (particularly poor peripheral vision) excessive thirst and frequent urination growth failure delayed or premature puberty nausea [pituitary.mgh.harvard.edu]

  Vision changes, lethargy and nausea are common symptoms. How is it diagnosed? A pituitary neoplasm diagnosis can be complicated, as the symptoms are not unique to this condition. [clicks.co.za]

  Bromocriptine requires a once a day dosing regime and generally has more side effects including gastrointestinal upset, nausea and dizziness with getting up too fast. [aans.org]

• Osteoporosis

  […] and nonfunctioning pituitary adenoma: infertility amenorrhea (absence of menses or menstrual periods) oligomenorrhea (irregular/sparse menstruation) decreased libido (interest in sex) galactorrhea (breast milk production / leakage / nipple discharge) osteoporosis [pituitary.mgh.harvard.edu]

  In men, high prolactin levels can cause breast growth and erectile dysfunction (trouble with erections) Both men and women can have: Loss of interest in sex Infertility Weakening of the bones called osteoporosis If the tumor continues to grow, it can [cancer.org]

  It can also cause osteoporosis, which is weakening of the bones; loss of sex drive; infertility; irregular menstrual cycles; and erectile dysfunction. Adrenocorticotropic hormone. [cancer.net]

  Cushing disease [6, 10] Weight gain, centripetal obesity, moon facies, violet striae, easy bruisability, proximal myopathy, and psychiatric changes Other possible effects - Arterial hypertension, diabetes, cataracts, glaucoma, and osteoporosis [emedicine.medscape.com]

  Systemic symptoms include generalized weakness, fatigue, myopathy, and metabolic effects including hypertension, glucose intolerance, osteoporosis, menstrual abnormalities, and immunosuppression. [med.virginia.edu]

• Hirsutism

  Further changes in the voice, and hirsutism, confirm the diagnosis. Acromegaly frequently results in glucose intolerance, with 20% of patients progressing to diabetes mellitus. Respiratory difficulty and sleep apnea are fairly common. [emedicine.medscape.com]

  The classic presentation is one of rapid weight gain with striae, hypertension, growth failure, and pubertal failure or arrest, with hirsutism and premature pubarche in prepubertal children. [academic.oup.com]

  The Cushingoid features of patients with ACTH secreting adenomas include moon facies, centripetal obesity, ‘buffalo hump’, supraclavicular fat deposition, hirsutism, hyperpigmentation, plethora, vascular fragility, and abdominal striae. [med.virginia.edu]

  Hirsutism and acne indicating excessive androgen production, proximal myopathy and bone fractures all point to Cushing’s syndrome. Only 3 cases of pregnancy in women with thyroid stimulating hormone (TSH)-secreting adenomas have been reported. [clinicaladvisor.com]

  In women it may cause excessive growth of facial hair ( hirsutism ) and in men erectile dysfunction. Psychiatric manifestations may include depression, anxiety, easy irritability and emotional instability. [en.wikipedia.org]

• Hemianopsia

  Cushing-like effects, diplopia, bitemporal hemianopsia and diabetes insipidus are some of many symptoms that can be encountered. [symptoma.com]

  The most common problem is to lose vision in the outer fields (peripheral vision), called a bitemporal hemianopsia. Often patients do not notice this, as they correct for the problem by moving their head back and forth. [houstonmethodist.org]

  This type of pituitary adenoma results in: • Blurry vision • Loss of peripheral vision, called bitemporal hemianopsia • Loss of color perception, the ability to distinguish colors • Headache Pituitary apoplexy can be a severe result of any type of pituitary [texasspineandneurosurgerycenter.com]

  The classic presentation of the visual deficit is a bitemporal hemianopsia, but central scotomas and generalized blurring of vision are sometimes the complaint. [med.virginia.edu]

  Visual studies are important for evaluating any possible or existing visual field defects caused by large tumors that compress the optic pathways; bitemporal hemianopsia (loss of peripheral visual field) is the classic finding when a pituitary tumor compresses [skullbaseinstitute.com]

• Diplopia

  […] muscle weakness exertional intolerance and shortness of breath oligomehnorrhea (decreased menstrual flow) nervousness and irritability other mental disturbances sleep disturbances (including insomnia) changes in vision, photophobia, eye irritation, diplopia [pituitary.mgh.harvard.edu]

  Cushing-like effects, diplopia, bitemporal hemianopsia and diabetes insipidus are some of many symptoms that can be encountered. [symptoma.com]

  However, the physical signs that are typically present with large pituitary tumors such as bitemporal hemianopsia, diplopia or often signs of III, IV, VI nerve palsies are not present. [clinicaladvisor.com]

  The resultant extraocular palsy produces diplopia and visual blurring. Headache is frequently associated with large pituitary tumors. There is no characteristic pattern because both the location and intensity of the pain vary widely. [glowm.com]

  […] case of malignant ASCO with repeating recurrences and a high Ki-67 index-a challenging diagnosis guided by clinical presentations, radiological signs, and postoperative pathological tests.We represent a 30-year-old man who had suffered from headaches, diplopia [cancerindex.org]

• Blurred Vision

  Patients with involvement of one optic nerve may notice dim, dark, or blurred vision in one eye. Occasionally this may be noted when one happens to cover one eye and notes that they can't see out of the opposite eye. [willseye.org]

  Their growth can compress nearby cranial nerves, causing blind spots, blurred vision, or double vision. Pituitary tumors also can cause symptoms through the overproduction of hormones. [neurosurgery.wustl.edu]

  Pressure from these tumors on nearby structures can cause of wide range of symptoms, including: Body hair loss Change in the amount and frequency of urination Decrease in sexual libido, usually in men Dizziness Double vision, blurred vision or peripheral [loyolamedicine.org]

• Visual Impairment

  Nonendocrine complications of radiotherapy have included up to 20-fold increase in second tumors within the radiation field, visual impairment and problems with memory. [academic.oup.com]

  One of the most common symptoms is visual impairment, which results from compression of the optic chiasm due to suprasellar extension. 27 Characteristically, there is bilateral loss of vision in the superior temporal quadrants. [glowm.com]

• Peripheral Vision Loss

  Pressure from these tumors on nearby structures can cause of wide range of symptoms, including: Body hair loss Change in the amount and frequency of urination Decrease in sexual libido, usually in men Dizziness Double vision, blurred vision or peripheral [loyolamedicine.org]

• Loss of Libido

  Symptoms include: Erectile dysfunction Infertility Irregular menstrual periods Loss of libido Loss of menstrual periods Milky discharge from breasts Thyroid-stimulating hormone (TSH) These tumors are rare, but can lead to hyperthyroidism. [loyolamedicine.org]

  Hyperprolactinemia symptoms could include menstruation irregularities and other menstrual problems, breast discharge in women, loss of libido, sexual dysfunction and headaches. [uwhealth.org]

  Symptoms of pituitary tumors include vision loss, frequent headaches, fatigue, loss of menses, loss of libido, and weight change. Each of these symptoms can be caused by other medical conditions. [med.unc.edu]

  Here, too, menstrual irregularity is common as are infertility and loss of libido. If the excess production of prolactin is prolonged, osteoporosis becomes an issue as well. [pituitary.org]

  Manifestations may include hypogonadism (sexual dysfunction, loss of libido, and impotence), hypothyroidism (fatigue, weakness, weight gain, coarse dry hair and dry skin, cold intolerance, depression), adrenal insufficiency (fatigue, weakness, loss of [pacificneuroscienceinstitute.org]

• Withdrawn

  Neoplasm Trials Pituitary Neoplasm Acromegaly Pituitary Tumor Abnormalities Adenoma Central Diabetes Insipidus Any 17 and under 18 - 34 35 - 50 51 - 69 70+ Available Active, not recruiting Not yet recruiting Recruiting Completed Terminated Suspended Withdrawn [patientwing-dev.vitaltrax.net]

• Headache

  Rarely, hemorrhage into a pituitary tumor causes pituitary apoplexy, with sudden headache, ophthalmoplegia, and visual loss. [msdmanuals.com]

  Given the low threshold for performing central nervous system imaging in patients with headaches, the natural history of this disease may be changing. [academic.oup.com]

  The clinical presentation mainly depends on hormone-secreting effects, but a headache may often be the only symptom. [symptoma.com]

  These tumors may grow large enough to cause symptoms such as headaches and vision problems before they are found. (See the symptoms for large tumors above.) [cancer.org]

• Bitemporal Hemianopsia

  Cushing-like effects, diplopia, bitemporal hemianopsia and diabetes insipidus are some of many symptoms that can be encountered. [symptoma.com]

  The most common problem is to lose vision in the outer fields (peripheral vision), called a bitemporal hemianopsia. Often patients do not notice this, as they correct for the problem by moving their head back and forth. [houstonmethodist.org]

  This type of pituitary adenoma results in: • Blurry vision • Loss of peripheral vision, called bitemporal hemianopsia • Loss of color perception, the ability to distinguish colors • Headache Pituitary apoplexy can be a severe result of any type of pituitary [texasspineandneurosurgerycenter.com]

  The classic presentation of the visual deficit is a bitemporal hemianopsia, but central scotomas and generalized blurring of vision are sometimes the complaint. [med.virginia.edu]

  Visual studies are important for evaluating any possible or existing visual field defects caused by large tumors that compress the optic pathways; bitemporal hemianopsia (loss of peripheral visual field) is the classic finding when a pituitary tumor compresses [skullbaseinstitute.com]

• Apathy

  "Apathy and pituitary disease: it has nothing to do with depression". The Journal of Neuropsychiatry and Clinical Neurosciences. 17 (2): 159–66. doi : 10.1176/appi.neuropsych.17.2.159. PMID 15939968. ^ "Acromegaly and Gigantism". Merck.com. [en.wikipedia.org]

• Sexual Dysfunction

  Hyperprolactinemia symptoms could include menstruation irregularities and other menstrual problems, breast discharge in women, loss of libido, sexual dysfunction and headaches. [uwhealth.org]

  In contrast, men usually present in the fourth or fifth decades of life and have sexual dysfunction and symptoms related to mass effect attributable to an enlarging sellar mass. [med.virginia.edu]

  Some common symptoms include: Vision problems Headaches Nausea and vomiting Unexplained weight change Menstrual cycle changes in women Sexual dysfunction Please note that the presence of these symptoms alone do not mean that you have a pituitary tumor [barrowneuro.org]

  Compression of the pituitary gland by a hormone-inactive tumor can result some form of pituitary failure with one or more of the following pituitary tumor symptoms : • Low blood pressure • Fatigue • Inability to handle stress • Sexual dysfunction Compression [texasspineandneurosurgerycenter.com]

• Amenorrhea

  They may cause discharge from breasts (galactorrhea), irregular periods (oligomenorrhea) or loss of normal menstrual function (amenorrhea) in females and impotence in men. [my.clevelandclinic.org]

  Prolactinoma and nonfunctioning pituitary adenoma: infertility amenorrhea (absence of menses or menstrual periods) oligomenorrhea (irregular/sparse menstruation) decreased libido (interest in sex) galactorrhea (breast milk production / leakage / nipple [pituitary.mgh.harvard.edu]

  In the case of prolactinoma amenorrhea, galactorrhea and infertility may be encountered, while acromegaly and gigantism are usually the result of GH-secreting pituitary adenoma. [symptoma.com]

  In women, this can cause loss of menstrual periods (amenorrhea) and fluid discharge from the breasts (galactorrhea). [willseye.org]

  Panhypopituitarism - Refers to deficiency of several anterior pituitary hormones; may occur in a slowly progressive fashion (eg, pituitary adenomas) Hormonal overproduction - Clinical effects Prolactin Hypogonadism, if hyperprolactinemia sustained Women - Amenorrhea [emedicine.medscape.com]

A detailed patient history and a thorough physical examination may provide sufficient information to suspect a pituitary neoplasm. Obvious signs such as acromegaly and galactorrhea, strongly suggest the presence of the pituitary tumor, after which appropriate laboratory and imaging studies need to be done. Levels of PRL, insulin-like growth factor 1 (IGF-1), LH, FSH, TSH, and ACTH should be obtained. The diagnosis of prolactinoma can be made solely on laboratory findings [12]. MRI is used to confirm the presence of a pituitary tumor and identify its exact location, but because tumors may be very small, 1-mm thick slices are recommended [4]. If patients report a family history of other endocrine tumors, a detailed diagnostic workup toward identifying potential familial syndromes such as MEN 1 should be conducted.

• Enlarged Sella

  A pituitary tumor tends to produce an enlarged sella (sella turcica). Alternatively, an enlarged sella may represent empty sella syndrome. [merckmanuals.com]

• Hyperprolactinemia

  This leads to loss of function of these end glands Hyperprolactinemia: Hyperprolactinemia is commonly caused by a benign pituitary tumor. [uwhealth.org]

  However, there is a recurrence rate of hyperprolactinemia of about 20% so that the true long-term remission rate is only 50% to 60. [clinicaladvisor.com]

  This would imply that patients with hyperprolactinemia have an abnormality in GnRH pulsatility. [glowm.com]

  In the presence of secondary hypogonadism and after excluding reversible factors that may cause hyperprolactinemia, treatment should be started. [academic.oup.com]

  The following symptoms may be related to pituitary tumors (adenoma) and the diseases they cause (e.g. acromegaly, Cushing's disease, hyperprolactinemia). Pituitary tumors can cause any one or more than one of the symptoms. [pituitary.mgh.harvard.edu]

After the diagnosis of a pituitary neoplasm is made by MRI, treatment depends on various factors, such as the size, location, and a presence of symptoms. Large, symptomatic tumors are often surgically handled as soon as possible, most likely via the transsphenoidal approach. Not all tumors have to be surgically handled, as some respond to pharmacologic therapy quite well. Dopamine agonists, such as bromocriptine, are shown to be very effective against prolactinomas and often cause sufficient tumor shrinkage with marked reduction of prolactin synthesis [12]. Growth hormone receptor antagonists and somatostatin analogs are used in the case of GH-secreting adenoma, while steroidogenesis inhibitors are often used as adjunctive therapy in ACTH-secreting tumors [8]. Radiotherapy is often used as first or second-line therapy in managing pituitary neoplasms, as they are shown to be very sensitive to radiation and their main use is in the post-operative setting [8]. Studies have shown that adjunctive radiation therapy, especially when complete excision of the tumor is not possible, is significantly better over surgery alone [13].

When it comes to surgery, indications include symptomatic patients, both secretory and nonsecretory tumors of a large size that cause local tissue destruction. Microadenomas that are discovered incidentally may not require surgical therapy but should be followed up instead. The transsphenoidal approach, although shown to be one of the most favored approaches in managing pituitary neoplasms, carries several risks. Olfactory injury and pituitary apoplexy are some of the most important [14] , which is why all attempts to manage these tumors conventionally should be made. However, with the introduction of intraoperative MRI examination [15], higher complete excision rates have been observed.

An early diagnosed neoplasm carries a very good prognosis. These tumors are almost universally benign, as cases of malignant pituitary tumors are extremely rare. However, in the case of large adenomas which cause significant damage to the optic chiasm and surrounding structures, patients could have a serious clinical picture. Additionally, numerous complications may arise during surgical therapy, especially in the setting of a large pituitary neoplasm, which is why an early diagnosis significantly improves chances of a successful treatment.

The pituitary gland is composed of two lobes: the anterior (adenohypophysis) and posterior (neurohypophysis), with each region containing cells that create specific hormones. In the anterior lobe, there are several cell types, each having distinct physiological function [3]:

• Thyrotroph cells synthesize thyroid-stimulating hormone (TSH).
• Somatotroph cells produce growth hormone (GH).
• Gonadotroph cells secrete luteinizing (LH) and follicle-stimulating hormone (FSH).
• Corticotroph cells secrete adrenocorticotropic hormone (ACTH)
• Lactotroph cells produce prolactin (PRL).

Oxytocin and vasopressin (antidiuretic hormone or ADH), on the other hand, are produced in the posterior hypophysis from magnocellular neurons. Each of these cellular types can be a source of neoplastic growth, resulting in the development of adenoma. These tumors can be described as secretory or nonsecretory and their clinical presentation directly depends on presence or absence of the hormone production [2]. Craniopharyngiomas, however, arise from squamous rest cells that are located between the two pituitary lobes. Several gene mutations have been discovered in patients with pituitary neoplasms and are thought to be the main causative factors. In the case of adenoma PTTG [9] and several other genes are involved. Galectin-3, a beta-galactoside-binding protein, is a significant factor in pituitary tumor formation [10]. Genetic processes in craniopharyngiomas remain incompletely resolved, but mutations in the β-catenin gene are confirmed in these neoplasms [2].

Approximately 10-15% of all intracranial tumors are pituitary neoplasms and numerous studies have established that these lesions are not uncommon in the general population. Prevalence rates are estimated to range from 10-16.7% in some larger samples, while macroadenomas are seen in 1 in 600 individuals [4] [5]. Other studies report much higher rates of these tumors, up to 38% [5], implying that many individuals with microadenomas are undiagnosed, presumably because a significant percentage of these tumors are nonsecretory and very small. The majority of pituitary tumors are adenomas (approximately 90%) [1]. Craniopharyngiomas, however, comprise between 80-90% of pituitary tumors seen in childhood and their peak incidence is shown to be between 5-14 years [3]. Apart from a family history of pituitary tumors or MEN 1, no other risk factors have been identified so far.

The pathogenesis model invariably includes genetic factors and various protein molecular changes have been identified. In the case of secreting adenomas, the cascade starts with alterations in G-proteins as a result of gene mutations. G proteins are a basic component of signal transduction, and they are responsible for transmission of signals from cell surface receptors to intracellular effectors, which are responsible for a generation of second messengers. Certain molecular changes of G-proteins lead to a persistent generation of important second messenger cAMP, with resultant uncontrolled cellular proliferation [2]. In addition, various genes, such as those which encode for galectin-3 protein and PTTG, exhibit mutations. In craniopharyngiomas, β-catenin gene mutations have been observed in about 20% of patients.

Although the pathogenesis of pituitary neoplasms is mainly well understood, no preventive measures exist. An early diagnosis that can be achieved through detailed evaluation of patients with unexplained headaches and other accompanying symptoms, can undoubtedly lead to better outcomes.

Pituitary neoplasms comprise 10-15% of all intracranial tumors and are almost universally benign [1]. Pituitary adenomas and craniopharyngiomas are the two most common types, with somewhat different prevalence rates among age groups. Adenomas are divided based on the presence or absence of hormone production. Prolactin (PRL), growth hormone (GH), adrenocorticotropic hormone (ACTH), thyroid-stimulating hormone (TSH), follicle-stimulating hormone (FSH) and luteinizing hormone (LH) are all synthesized in the pituitary gland and depending on the location of the tumor, one or more hormones may be secreted [2]. Adenomas comprise almost 90% of pituitary tumors in adults [1], while craniopharyngiomas constitute 80-90% of pituitary fossa tumors found in children [3]. Estimated prevalence rate between 10-16.7% suggest that this tumor is rather often in the general population (although not all of them cause symptoms), while very large adenomas ( > 1cm, or macroadenomas) are thought to develop in approximately 1 in 600 individuals [4] [5]. These tumors may also appear as constituents of familial syndromes such as multiple endocrine neoplasia type 1 (MEN 1), in which concomitant development of pituitary, pancreatic and parathyroid neoplasms are observed. Various gene mutations have been established in the pathogenesis of pituitary neoplasms. Molecular changes of various genes, such as PRKAR1A and pituitary tumor transforming gene (PTTG) are seen in pituitary adenomas [6] [7]. On the other hand, β-catenin gene mutations are seen in craniopharyngiomas, along with various cytogenetic abnormalities [2]. The clinical presentation mainly depends on hormone-secreting effects, but a headache may often be the only symptom. In the case of prolactinoma amenorrhea, galactorrhea and infertility may be encountered, while acromegaly and gigantism are usually the result of GH-secreting pituitary adenoma. Cushing-like effects, diplopia, bitemporal hemianopsia and diabetes insipidus are some of many symptoms that can be encountered. To make the diagnosis, magnetic resonance imaging (MRI) is the gold standard, together with an evaluation of hormone levels that are suspected to be abnormal based on clinical findings [8]. Treatment principles depend on the location, size and secretory properties of the tumor. Surgical excision of the tumor via the transsphenoidal approach is often indicated as the first-line therapy, but some tumors may be handled without surgery. Prolactinomas are effectively treated by dopamine agonists, such as bromocriptine, while somatostatin analogs and GH-receptor antagonists together with radiotherapy are being used in GH-secreting tumors [8].

Pituitary neoplasms arise from the pituitary gland, one of the most important glands in our body, since it secretes various hormones that regulate a vast number of important functions in the body. In general, tumors of the pituitary are divided into two major groups: adenomas (constitute approximately 90% of all pituitary tumors in adults ) and craniopharyngiomas (80-90% of pituitary tumors in children). Additionally, adenomas can be classified into a secreting and nonsecreting group, meaning that the cells affected by neoplastic growth may secrete abnormal amounts of hormones or remain inactive. Growth hormone, prolactin, adrenocorticotropic hormone (ACTH), gonadal hormones and thyroid-stimulating hormone (TSH) are all synthesized and secreted inside the pituitary gland and tumors may arise from each of the cells that are responsible for their production. Consequently, overproduction of hormones is often encountered in adenomas and result in characteristic symptoms. Tumors of cells that create prolactin (prolactinomas) cause symptoms such as gynecomastia (enlarged breasts), galactorrhea (milk discharge from the breasts) and infertility, while neoplasia of growth hormone secreting cells will cause a profound growth of hands, feet and the jaw (acromegaly). Various other symptoms may be seen, including headaches, visual problems, hypertension, central obesity, but hypopituitarism (reduced secretion of hormones) may be encountered as well, especially in craniopharyngiomas. To make the diagnosis, establishing levels of pituitary hormones and magnetic resonance imaging of the head (MRI) is imperative. Once the tumor is confirmed, treatment depends on the tumor type. Prolactinomas are treated only by drugs, specifically dopamine agonists such as bromocriptine, which suppress prolactin production and tumor growth, but surgical excision is usually the preferred method for all other tumors. Surgery is performed through the nose and the sinus that is below the pituitary gland (the sphenoid sinus), which is why it is called "transsphenoidal" surgery. Radiation and adjunctive drugs may be used to facilitate better outcomes. This tumor has a very good prognosis if caught and treated early so that minimal damage to adjacent tissues is made. In larger tumors that have caused local tissue destruction, however, persistent neurological symptoms such as visual changes may ensue, which is why early recognition is the key.

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