Pheochromocytoma is seen in between two and eight in 1,000,000, with approximately 1000 cases diagnosed in United States yearly. It mostly occurs in young or middle age adults, though it presents earlier in hereditary cases.

- About 10% of adrenal cases are bilateral (suggesting hereditary disease)

- About 10% of adrenal cases occur in children (also suggesting hereditary disease)

- About 15% are extra-adrenal (located in any orthosympathetic tissue): Of these 9% are in the abdomen, and 1% are located elsewhere. Some extra-adrenal pheochromocytomas are probably actually paragangliomas, but the distinction can only be drawn after surgical resection.

- About 11.1% of adrenal cases are malignant, but this rises to 30% for extra-adrenal cases

- About 15–20% are hereditary

- About 5% are caused by VHL disease

- About 3% recur after being resected

- About 14% of affected individuals do not have arterial hypertension (Campbell's Urology)

The massive release of catecholamines in pheochromocytoma can cause damage to heart cells. This damage may be due to either compromising the coronary microcirculation or by direct toxic effects on the heart cells.

An endocrine gland neoplasm is a neoplasm affecting one or more glands of the endocrine system.

Examples include:

- Adrenal tumor

- Pituitary adenoma

The most common form is thyroid cancer.

Condition such as pancreatic cancer or ovarian cancer can be considered endocrine tumors, or classified under other systems.

Pinealoma is often grouped with brain tumors because of its location.

ACC, generally, carries a poor prognosis and is unlike most tumours of the adrenal cortex, which are benign (adenomas) and only occasionally cause Cushing's syndrome. Five-year disease-free survival for a complete resection of a stage I–III ACC is approximately 30%.

The most important prognostic factors are age of the patient and stage of the tumor.

Poor prognostic factors: mitotic activity, venous invasion, weight of 50g+; diameter of 6.5 cm+, Ki-67/MIB1 labeling index of 4%+, p53+.

An adrenal tumor or adrenal mass is any benign or malignant neoplasms of the adrenal gland, several of which are notable for their tendency to overproduce endocrine hormones. Adrenal cancer is the presence of malignant adrenal tumors, and includes neuroblastoma, adrenocortical carcinoma and some adrenal pheochromocytomas. Most adrenal pheochromocytomas and all adrenocortical adenomas are benign tumors, which do not metastasize or invade nearby tissues, but may cause significant health problems by unbalancing hormones.

A physician's response to detecting an adenoma in a patient will vary according to the type and location of the adenoma among other factors. Different adenomas will grow at different rates, but typically physicians can anticipate the rates of growth because some types of common adenomas progress similarly in most patients. Two common responses are removing the adenoma with surgery and then monitoring the patient according to established guidelines.

One common example of treatment is the response recommended by specialty professional organizations upon removing adenomatous polyps from a patient. In the common case of removing one or two of these polyps from the colon from a patient with no particular risk factors for cancer, thereafter the best practice is to resume surveillance colonoscopy after 5–10 years rather than repeating it more frequently than the standard recommendation.

Adrenocortical carcinoma (ACC, adrenal cortical carcinoma, adrenal cortical cancer, adrenal cortex cancer, etc.) is an aggressive cancer originating in the cortex (steroid hormone-producing tissue) of the adrenal gland. Adrenocortical carcinoma is a rare tumor, with incidence of 1–2 per million population annually. Adrenocortical carcinoma has a bimodal distribution by age, with cases clustering in children under 5, and in adults 30–40 years old. Adrenocortical carcinoma is remarkable for the many hormonal syndromes which can occur in patients with steroid hormone-producing ("functional") tumors, including Cushing's syndrome, Conn syndrome, virilization, and feminization. Adrenocortical carcinoma has often invaded nearby tissues or metastasized to distant organs at the time of diagnosis, and the overall 5-year survival rate is only 20–35%. The widely used angiotensin-II-responsive steroid-producing cell line H295R was originally isolated from a tumor diagnosed as adrenocortical carcinoma.

The adrenal cortex is composed of three distinct layers of endocrine cells which produce critical steroid hormones. These include the glucocorticoids which are critical for regulation of blood sugar and the immune system, as well as response to physiological stress, the mineralcorticoid aldosterone, which regulates blood pressure and kidney function, and certain sex hormones. Both benign and malignant tumors of the adrenal cortex may produce steroid hormones, with important clinical consequences.

Depending on source, the overall 5-year survival rate for medullary thyroid cancer is 80%, 83% or 86%, and the 10-year survival rate is 75%.

By overall cancer staging into stages I to IV, the 5-year survival rate is 100% at stage I, 98% at stage II, 81% at stage III and 28% at stage IV. The prognosis of MTC is poorer than that of follicular and papillary thyroid cancer when it has metastasized (spread) beyond the thyroid gland.

The prognostic value of measuring calcitonin and carcinoembryonic antigen (CEA) concentrations in the blood was studied in 65 MTC patients who had abnormal calcitonin levels after surgery (total thyroidectomy and lymph node dissection). The prognosis correlated with the rate at which the postoperative calcitonin concentration doubles, termed the calcitonin doubling time (CDT), rather than the pre- or postoperative absolute calcitonin level:

- CDT less than 6 months: 3 patients out of 12 (25%) survived 5 years. 1 patient out of 12 (8%) survived 10 years. All died within 6 months to 13.3 years.

- CDT between 6 months and 2 years: 11 patients out of 12 (92%) survived 5 years. 3 patients out of 8 (37%) survived 10 years. 4 patients out of 12 (25%) survived to the end of the study.

- CDT more than 2 years: 41 patients out of 41 (100%) were alive at the end of the study. These included 1 patient whose calcitonin was stable, and 11 patients who had decreasing calcitonin levels.

The calcitonin doubling time was a better predictor of MTC survival than CEA but following both tests is recommended.

An adenoma (from Greek αδένας, "", "gland" + -ώμα, "", "tumor") (; plural adenomas or adenomata ) is a benign tumor of epithelial tissue with glandular origin, glandular characteristics, or both. Adenomas can grow from many glandular organs, including the adrenal glands, pituitary gland, thyroid, prostate, and others. Some adenomas grow from epithelial tissue in nonglandular areas but express glandular tissue structure (as can happen in familial polyposis coli). Although adenomas are benign, over time they may transform to become malignant, at which point they are called adenocarcinomas. Most adenomas do not transform. But even while benign, they have the potential to cause serious health complications by compressing other structures (mass effect) and by producing large amounts of hormones in an unregulated, non-feedback-dependent manner (causing paraneoplastic syndromes). Some adenomas are too small to be seen macroscopically but can still cause clinical symptoms.

Without treatment, persons with MEN2B die prematurely. Details are lacking, owing to the absence of formal studies, but it is generally assumed that death in the 30s is typical unless prophylactic thyroidectomy and surveillance for pheochromocytoma are performed (see below). The range is quite variable, however: death early in childhood can occur, and it is noteworthy that a few untreated persons have been diagnosed in their 50s. Recently, a larger experience with the disease "suggests that the prognosis in an individual patient may be better than previously considered."

Thyroidectomy is the mainstay of treatment, and should be performed without delay as soon as a diagnosis of MEN2B is made, even if no malignancy is detectable in the thyroid. Without thyroidectomy, almost all patients with MEN2B develop medullary thyroid cancer, in a more aggressive form than MEN 2A. The ideal age for surgery is 4 years old or younger, since cancer may metastasize before age 10.

Pheochromocytoma - a hormone secreting tumor of the adrenal glands - is also present in 50% of cases. Affected individuals are encouraged to get yearly screenings for thyroid and adrenal cancer.

Because prophylactic thyroidectomy improves survival, blood relatives of a person with MEN2B should be evaluated for MEN2B, even if lacking the typical signs and symptoms of the disorder.The mucosal neuromas of this syndrome are asymptomatic and self-limiting, and present no problem requiring treatment. They may, however, be surgically removed for aesthetic purposes or if they are being constantly traumatized.

A adrenocortical adenoma (or adrenal cortical adenoma, or sometimes simply adrenal adenoma) is a benign tumor of the adrenal cortex.

It can present with Cushing's syndrome or primary aldosteronism. They may also secrete androgens, causing hyperandrogenism. Also, they are often diagnosed incidentally as incidentalomas.

Is a well circumscribed, yellow tumour in the adrenal cortex, which is usually 2–5 cm in diameter. The color of the tumour, as with adrenal cortex as a whole, is due to the stored lipid (mainly cholesterol), from which the cortical hormones are synthesized. These tumors are frequent incidental findings at post mortem examination, and appear to have produced no significant metabolic disorder; only a very small percentage lead to Cushing's syndrome. Nevertheless, these apparently non-functioning adenomas are most often encountered in elder obese people. There is some debate that they may really represent nodules in diffuse nodular cortical hyperplasia.

Very occasionally, a true adrenal cortical adenoma is associated with the clinical manifestations of Conn's syndrome, and can be shown to be excreting mineralocorticoids.

Variations in the RET proto-oncogene cause MEN2B. In recent decades no case of MEN2B has been reported that lacks such a variation. The M918T variant alone is responsible for approximately 95% of cases. All DNA variants that cause MEN2B are thought to enhance signaling through the RET protein, which is a receptor molecule found on cell membranes, whose ligands are part of the transforming growth factor beta signaling system.

About half of cases are inherited from a parent as an autosomal dominant trait. The other half appear to be spontaneous mutations, usually arising in the paternal allele, particularly from older fathers. The sex ratio in de novo cases is also uneven: sons are twice as likely to develop MEN 2B as daughters.

Hyperplasia may be due to any number of causes, including increased demand (for example, proliferation of basal layer of epidermis to compensate skin loss), chronic inflammatory response, hormonal dysfunctions, or compensation for damage or disease elsewhere. Hyperplasia may be harmless and occur on a particular tissue. An example of a normal hyperplastic response would be the growth and multiplication of milk-secreting glandular cells in the breast as a response to pregnancy, thus preparing for future breast feeding.

Perhaps the most interesting and potent effect IGF has on the human body is its ability to cause hyperplasia, which is an actual splitting of cells. By contrast, hypertrophy is what occurs, for example, to skeletal muscle cells during weight training and steroid use and is simply an increase in the size of the cells. With IGF use, one is able to cause hyperplasia which actually increases the number of muscle cells present in the tissue. Weight training with or without anabolic steroid use enables these new cells to mature in size and strength. It is theorized that hyperplasia may also be induced through specific power output training for athletic performance, thus increasing the number of muscle fibers instead of increasing the size of a single fiber.

Medullary thyroid cancer (MTC) is a form of thyroid carcinoma which originates from the parafollicular cells (C cells), which produce the hormone calcitonin.

Medullary tumors are the third most common of all thyroid cancers. They make up about 3% of all thyroid cancer cases.

Approximately 25% of medullary thyroid cancer is genetic in nature, caused by a mutation in the RET proto-oncogene. This form is classified as familial MTC. When MTC occurs by itself it is termed sporadic MTC. When it coexists with tumors of the parathyroid gland and medullary component of the adrenal glands (pheochromocytoma) it is called multiple endocrine neoplasia type 2 (MEN2).It was first characterized in 1959.

Hyperplasia is considered to be a physiological (normal) response to a specific stimulus, and the cells of a hyperplastic growth remain subject to normal regulatory control mechanisms. However, hyperplasia can also occur as a pathological response, if an excess of hormone or growth factor is responsible for the stimuli. Similarly to physiological hyperplasia, cells that undergo pathologic hyperplasia are controlled by growth hormones, and cease to proliferate if such stimuli are removed. This differs from neoplasia (the process underlying cancer and benign tumors), in which genetically abnormal cells manage to proliferate in a non-physiological manner which is unresponsive to normal stimuli. That being said, the effects caused by pathologic hyperplasia can provide a suitable foundation from which neoplastic cells may develop.

Myelolipomas are rare. They have been reported to be found unexpectedly at autopsy in 0.08% to 0.4% of cases ("i.e.:" somewhere between 8 per 10,000 and 4 per 1,000 autopsies). They most commonly occur in the adrenal gland, yet only comprise about 3% of all adrenal tumours. They may also occur in other sites, such as the mediastinum, the liver and the gastrointestinal tract.

There is no gender predilection, males and females are affected equally. The peak age range at diagnosis is between 40 and 79 years of age.

PPNAD, the endocrine manifestation that comes from Carney Complex (CNC), can be syndromic or isolated. The main cause of isolated PPNAD is a mutation of PRKAR1α, located at 17q22-24, which is the gene encoding the regulatory R1α subunit of protein kinase A. Germline heterozygous PRKAR1α inactivation mutations are present in 80% of CNC patients affected by Cushing's syndrome. There are over 117 mutations of the PRKAR1α gene that can cause CNC, with many of these mutations producing premature stop codons, thus resulting in the complete loss of PRKAR1α protein. CNC patients have also been discovered with an unusually shortened PRKAR1α protein, detected in tumours and leukocytes, following a splice-site mutation, which causes exon-6 skipping. Therefore, both haploinsufficiency and the complete loss of PRKAR1α can lead to the increased PKA activity observed in PPNAD patients, due to the disruption of the cAMP signalling pathway.

Sahut-Barnola et al. used a mouse model to cre-lox knockout the Prkar1a gene specifically from cells of the adrenal cortex and observed that the mice subsequently developed Cushing syndrome that is independent of the pituitary. They also observed that the mutation caused increased PKA activity.

The R1α loss caused the adult adrenal gland became hyperactive and hyperplastic on both sides, as seemingly the foetal adrenal cells within it were not maintained and thus expanded. This established tumoral growths. This mouse KO model phenocopies what happens in human cases of PPNAD.

Inactivation of PDE11A4, located at 2q31-5, has also been identified in PPNAD patients without PRKAR1α mutations. PDE11A4 is the gene encoding phosphodiesterase 11A4, another participant of the cAMP signalling pathway.

The majority of myelolipomas are asymptomatic. Most do not produce any adrenal hormones. Most are only discovered as a result of investigation for another problem.

When myelolipomas do produce symptoms, it is usually because they have become large, and are pressing on other organs or tissues nearby. Symptoms include pain in the abdomen or , blood in the urine, a palpable lump or high blood pressure.

As they are benign tumors, myelolipomas do not spread to other body parts. Larger myelolipomas are at risk of localised tissue death and bleeding, which may cause a retroperitoneal haemorrhage.

Primary pigmented nodular adrenocortical disease (PPNAD) was first coined in 1984 by Carney et al. it often occurs in association with Carney complex (CNC). CNC is a rare syndrome that involves the formation of abnormal tumours that cause endocrine hyperactivity.

PPNAD arises due to the enlargement of the cortex of the adrenal glands, resulting in Cushing's syndrome that is independent of the pituitary hormone ACTH.

Iatrogenic Cushing's syndrome (caused by treatment with corticosteroids) is the most common form of Cushing's syndrome. Cushing's disease is rare; a Danish study found an incidence of less than one case per million people per year. However, asymptomatic microadenomas (less than 10 mm in size) of the pituitary are found in about one in six individuals.

People with Cushing's syndrome have increased morbidity and mortality as compared to the general population. The most common cause of mortality in Cushing's syndrome is cardiovascular events. People with Cushing's syndrome have nearly 4 times increased cardiovascular mortality as compared to the general population.

Paragangliomas originate from paraganglia in chromaffin-negative glomus cells derived from the embryonic neural crest, functioning as part of the sympathetic nervous system (a branch of the autonomic nervous system). These cells normally act as special chemoreceptors located along blood vessels, particularly in the carotid bodies (at the bifurcation of the common carotid artery in the neck) and in aortic bodies (near the aortic arch).

Accordingly, paragangliomas are categorised as originating from a neural cell line in the World Health Organization classification of neuroendocrine tumors. In the categorization proposed by Wick, paragangliomas belong to group II. Given the fact that they originate from cells of the orthosympathetic system, paragangliomas are closely related to pheochromocytomas, which however are chromaffin-positive.

A paraganglioma is a rare neuroendocrine neoplasm that may develop at various body sites (including the head, neck, thorax and abdomen). Unlike other types of cancer, there is no test that determines benign from malignant tumors; long-term followup is therefore recommended for all individuals with paraganglioma. Approximately 50% of patients with recurrent disease experience distant metastasis. The five-year survival in the setting of metastatic disease is 40% to 45%.

Adrenal gland disorders (or diseases) are conditions that interfere with the normal functioning of the adrenal glands. Adrenal disorders may cause hyperfunction or hypofunction, and may be congenital or acquired.

The adrenal gland produces hormones that affects growth, development and stress, and also helps to regulate kidney function. There are two parts of the adrenal glands, the adrenal cortex and the adrenal medulla. The adrenal cortex produces mineralocorticoids, which regulate salt and water balance within the body, glucocorticoids (including cortisol) which have a wide number of roles within the body, and androgens, hormones with testosterone-like function. The adrenal medulla produces epinephrine (adrenaline) and norepinephrine (noradrenaline). Disorders of the adrenal gland may affect the production of one or more of these hormones.

Outcomes are typically good when treated. Most can expect to live relatively normal lives. Someone with the disease should be observant of symptoms of an "Addison's crisis" while the body is strained, as in rigorous exercise or being sick, the latter often needing emergency treatment with intravenous injections to treat the crisis.

Individuals with Addison's disease have more than a doubled mortality rate. Furthermore, individuals with Addison's disease and diabetes mellitus have an almost 4 time increase in mortality compared to individuals with only diabetes.