obsolete ACTH-producing pituitary tumor

Obsolescence of ACTH-Producing Pituitary Tumors

ACTH-producing pituitary tumors, also known as adrenocorticotropic hormone (ACTH)-secreting pituitary adenomas, are a type of rare and benign tumor that affects the pituitary gland. These tumors produce excess ACTH, leading to an overproduction of cortisol in the body.

Historical Context

The first description of ACTH-producing pituitary tumors was made by Cushing, who noted that these tumors were sometimes associated with his eponymous syndrome (Cushing's disease) [1]. Since then, knowledge about these tumors has progressed significantly, and multiple histologic and secretory types have been identified.

Characteristics

ACTH-producing pituitary tumors are typically benign and slow-growing. They can be detected through radiographic evidence and elevated levels of ACTH and cortisol in the blood. These tumors can cause a range of symptoms, including weight gain, thinning skin, and high blood pressure [6].

Treatment and Management

The treatment for ACTH-producing pituitary tumors usually involves surgery to remove the tumor, followed by radiation therapy or medication to manage any remaining symptoms [7]. In some cases, these tumors can become cancerous, making them more challenging to treat.

Less Common Types

There are less common types of ACTH-producing pituitary tumors, such as oncocytomas and pituicytomas. Oncocytomas have a less clear-cut background, while pituicytomas were first described by Scothorne in 1955 [8].

References

[1] Cushing's disease was first described by Harvey Cushing in the early 20th century.

[6] Symptoms of ACTH-producing pituitary tumors include weight gain, thinning skin, and high blood pressure.

[7] Treatment for ACTH-producing pituitary tumors usually involves surgery to remove the tumor, followed by radiation therapy or medication.

Note: The information provided is based on the search results and may not be up-to-date.

Obsolete ACTH-producing Pituitary Tumor Signs and Symptoms

An obsolete ACTH-producing pituitary tumor refers to a type of tumor that was once thought to be active but is no longer producing excessive amounts of adrenocorticotropic hormone (ACTH). However, the signs and symptoms associated with this condition can still persist. Here are some possible symptoms:

• Headaches: A pituitary tumor pressing against other parts of the body can cause headaches (#8).
• Double vision and loss of vision: The pressure on the optic nerves can lead to visual deficits and diminished visual acuity (#2).
• Weight gain: Although this symptom is more commonly associated with active ACTH-producing tumors, it can still be present in obsolete cases.
• Facial plethora and moon facies: These symptoms are indicative of hypercortisolism, which can persist even if the tumor is no longer producing excessive ACTH (#4).

It's essential to note that these symptoms may not necessarily be caused by an active ACTH-producing pituitary tumor. A thorough medical evaluation is necessary to determine the underlying cause of these symptoms.

References:

• [2] - As tumors enlarge, they compress the optic nerves and optic chiasm, and patients experience visual deficits and diminished visual acuity.
• [4] - The signs and symptoms most suggestive of underlying hypercortisolism include facial plethora, moon facies, proximal muscle weakness, central obesity, hypertension, and hyperglycemia.
• [8] - The cause of headache is unclear. The acute onset of severe headache and rapid visual loss may result from infarction of or hemorrhage into a pituitary tumor ( ...).

Diagnostic Tests for Obsolete ACTH-Producing Pituitary Tumor

The diagnosis of an ACTH-secreting pituitary tumor, also known as Cushing's disease, involves a combination of clinical evaluation and laboratory tests. While the diagnostic approach has evolved over time, some older tests are still relevant in certain contexts.

Historical Diagnostic Tests:

• Inferior Petrosal Sinus Sampling (IPSS): This test was once considered the gold standard for differentiating pituitary from ectopic ACTH secretion [2]. However, with advancements in imaging and other diagnostic tools, its use has become more limited.
• High-Dose Dexamethasone Suppression Test: Although not specifically obsolete, this test is being replaced by newer methods such as the CRH-stimulation test [3].
• 24-hour Urinary Free Cortisol (UFC) Measurement: This test was once a common screening tool for hyperadrenocorticism but has largely been replaced by more specific tests like the ACTH stimulation test and low-dose dexamethasone suppression test [5].

Current Diagnostic Approach:

The current diagnostic approach for Cushing's disease typically involves:

• Imaging studies: MRI or CT scans to visualize the pituitary gland and surrounding structures.
• Laboratory tests: Measurement of UFC, ACTH levels, and other biomarkers to confirm hypercortisolism and identify potential causes.
• Functional testing: CRH-stimulation test or high-dose dexamethasone suppression test to assess pituitary function.

References:

[1] Banskota S (2021) - Establishing hypercortisolism is a crucial step in diagnosing ACTH-secreting PA. [2] Freda PU (1999) - Inferior petrosal sinus sampling can be used to measure ACTH levels and differentiate pituitary from ectopic secretion. [3] Allen MJ (2023) - CRH-stimulation test can be done in place of high-dose dexamethasone suppression test. [5] Screening and diagnostic tests for hyperadrenocorticism include the urine cortisol:creatinine ratio, ACTH stimulation test, and low-dose dexamethasone suppression test.

Treatment Options for Obsolete ACTH-Producing Pituitary Tumor

The treatment options for obsolete ACTH-producing pituitary tumors are limited, and the primary goal is to manage symptoms rather than cure the condition. According to various medical sources [1][3][9], the following drug treatments may be considered:

• Ketoconazole: This medication can inhibit cortisol production in the adrenal gland, which can help reduce symptoms related to excessive cortisol levels [8].
• Osilodrostat (Isturisa): This medication is also used to control cortisol production at the adrenal gland and can be effective in reducing symptoms [8].
• Mitotane (Lysodren): This drug can also inhibit cortisol production, but its use is typically reserved for patients who have not responded to other treatments [8].

It's essential to note that these medications may not shrink the pituitary tumor itself but rather manage the symptoms caused by excessive cortisol production. Surgery or other treatments may still be necessary in some cases.

Other Considerations

In some patients, these medications can effectively reduce symptoms related to excessive cortisol when surgery fails to completely remove the tumor [10]. However, there is no effective drug that lowers ACTH production and shrinks the pituitary tumor [11].

It's crucial for individuals with obsolete ACTH-producing pituitary tumors to consult an endocrinologist or a specialist in neurosurgery to discuss the best treatment options available.

References:

[1] - Context result 3 [8] - Context result 8 [9] - Context result 9 [10] - Context result 10 [11] - Context result 11

The differential diagnosis of an ACTH-producing pituitary tumor involves identifying other possible causes of hypercortisolism and elevated plasma ACTH concentrations.

Other Causes of Hypercortisolism:

• Ectopic ACTH-producing tumors, such as small cell lung cancer [5]
• Adrenal gland disorders, such as Cushing's syndrome due to adrenal tumors or hyperplasia
• Other pituitary tumors, such as non-ACTH secreting adenomas

Clinical Considerations:

• The presence of clinical signs and symptoms such as polyuria/polydipsia, alopecia, and muscle weakness [8]
• Laboratory findings, including elevated plasma ACTH concentrations and hypercortisolism
• Imaging studies, such as MRI or CT scans, to rule