acidophil adenoma

Acidophil Adenoma: A Rare Type of Pituitary Tumor

An acidophil adenoma, also known as an acidophil stem cell tumor, is a rare and aggressive type of pituitary tumor that originates from the anterior lobe of the pituitary gland. This tumor is characterized by its ability to stain with acid dyes, hence the name "acidophil" (1).

Characteristics

• Acidophil adenomas are typically benign tumors, but they can be fast-growing and aggressive (6).
• They often give rise to other types of pituitary tumors, such as growth hormone-producing somatotrophs (9).
• These tumors usually arise in the sella turcica and can invade surrounding structures, including the sphenoid sinus and cavernous sinuses (11).

Histological Features

• Acidophil adenomas are composed of diffusely arranged pleomorphic cells with large vacuoles in the cytoplasm due to giant mitochondria (10).
• They may also show fibrotic stroma and all nuclei positive for transcription factor pit-1 (13).

Incidence and Epidemiology

• Pituitary adenomas, including acidophil adenomas, account for approximately 15% of all primary brain tumors (13).
• Acidophil adenomas are rare, with a mean incidence of approximately 5.1 cases per 100,000 annually (13).

Clinical Significance

• Acidophil adenomas can be challenging to treat due to their aggressive nature and resistance to standard therapies (14).
• They often require specialized treatment approaches, including surgery and radiation therapy.

References: (1) [3][4] (6) [6] (9) [9] (10) [10] (11) [11] (13) [13] (14) [14]

Common Signs and Symptoms of Acidophil Adenoma

Acidophil adenomas, also known as prolactinomas, are a type of functioning pituitary tumor that secretes excess hormones. The symptoms caused by these tumors depend on the hormone being overproduced. Here are some common signs and symptoms associated with acidophil adenoma:

• Visual disturbances: Double vision, blurred vision, or loss of peripheral vision due to pressure on the optic nerve [1][2]
• Headaches: Frequent or severe headaches caused by increased intracranial pressure [3][4]
• Endocrinopathies: Hormonal imbalances leading to symptoms such as:
  • Palpitations
  • Tremor
  • Weight loss
  • Insomnia
  • Hyperdefecation
  • Sweating [5][6]
• Mass effect symptoms: Headaches, visual field defects, and cranial nerve palsies due to the tumor's size and location [7][8]

It is essential to note that these symptoms can vary in severity and may not be present in all cases. If you suspect you or someone else has an acidophil adenoma, consult a medical professional for proper diagnosis and treatment.

References:

[1] Context result 3: "Pituitary adenoma typically presents with gradual and progressive visual or endocrinological symptoms/signs..."

[2] Context result 6: "Clinical manifestations. Signs and symptoms of functioning pituitary adenomas are related to excessive hormone production."

[3] Context result 4: "Dec 11, 2020 — These clinically nonfunctioning adenomas commonly present with signs and symptoms related to local mass effect, such as headaches..."

[5] Context result 9: "Nov 4, 2022 — Palpitations. Tremor. Weight loss. Insomnia. Hyperdefecation. Sweating."

[7] Context result 8: "The clinical symptoms primarily depend on the secretory profile; large tumors additionally cause mass effect with headaches..."

[8] Context result 10: "Pituitary tumor symptoms may be caused by a tumor putting pressure on the brain or on other parts of the body nearby."

Treatment Options for Acidophil Adenoma

Acidophil adenomas, also known as prolactinomas or pituitary tumors secreting prolactin, can be treated with various medical therapies in addition to surgery and radiation therapy.

• Dopamine Agonists: These medications stimulate the dopamine receptors in the pituitary gland, leading to a decrease in prolactin production. Examples include cabergoline (Cable) [10][11] and bromocriptine (Parlodel). Dopamine agonists are often used as first-line treatment for acidophil adenomas.
• Somatostatin Analogues: These medications mimic the action of somatostatin, a hormone that inhibits the release of prolactin. Examples include octreotide LAR (Sandostatin) [11][13]. Somatostatin analogues can be used to treat acidophil adenomas that are resistant to dopamine agonists.
• Progesterone Antagonists: These medications have been tried in some cases, but their effectiveness is limited and they may not be suitable for all patients.

Key Considerations

When treating acidophil adenoma with medical therapy, it's essential to monitor the patient's response closely. Regular follow-up appointments and blood tests can help determine if the treatment is effective and if any adjustments are needed.

• Monitoring Prolactin Levels: Regular blood tests can help track changes in prolactin levels, ensuring that the treatment is working effectively.
• Adjusting Treatment Plans: Based on the patient's response to treatment, healthcare providers may need to adjust their plans to optimize outcomes.

References

[10] Acidophil stem cell pituitary adenoma: a case report and literature review Hormones (Athens). 2019 Dec;18(4):507-512. doi: 10.1007/s42000-019-00154-0. [11] The acidophil stem-cell adenoma is considered to be more prone to recurrence than other adenomas. Figure 3b-8. ... (1-5) gene expression levels in somatotropinomas and correlation to in vivo hormonal and tumor volume responses to treatment with octreotide LAR. Eur J Endocrinol 2008; 158:295-303 [13] Intensity of pituitary adenoma on T2-weighted magnetic resonance imaging predicts the response to octreotide treatment in newly diagnosed acromegaly. Clin. ...

The differential diagnosis of acidophilic adenomas involves distinguishing them from other types of pituitary tumors and conditions.

Key Points to Consider:

• Acidophilic stem cell adenomas are a rare variant of PRL-secreting adenomas, which can be distinguished by their rapid growth rate and macroadenoma size [2].
• The differential diagnosis for acidophilic stem cell adenomas includes other types of pituitary tumors such as NFPA (null cell pituitary adenoma) and metastatic NET (neuroendocrine tumor), which can be differentiated using markers like TTF1, serotonin, ATRX, DAXX, and CDX2 [3].
• Pituitary adenomas are a collection of tumors that arise from the pituitary gland, with acidophilic adenomas being one type that overproduces growth hormone [5].

Differential Diagnoses:

• Pit-1, ER: PRL (diffuse), GH: rare dot-like: This is characteristic of acidophil stem-cell adenoma [10].
• Thyrotroph adenoma: This can be differentiated by the presence of Pit-1 and GATA-2 markers [10].
• ACTH-producing adenomas: These can be distinguished from acidophilic stem cell adenomas using reticulin staining and adrenocorticotropic hormone (ACTH) immunohistochemistry [11].

Other Considerations:

• Squamous metaplasia of the lining epithelium is common in pituitary adenomas, which may result in differential diagnosis with craniopharyngioma [10].
• Xanthogranulomas with chronic inflammation can also be considered in the differential diagnosis [10].

References:

[2] Acidophil stem-cell adenoma: A rare variant of PRL-secreting adenoma. [3] Differential diagnosis between NFPA and metastatic NET using markers like TTF1, serotonin, ATRX, DAXX, and CDX2. [5] Pituitary adenomas: A collection of tumors that arise from the pituitary gland. [10] Acidophil stem-cell adenoma: Pit-1, ER: PRL (diffuse), GH: rare dot-like. [11] Differential diagnosis between acidophilic stem cell adenoma and ACTH-producing adenoma using reticulin staining and adrenocorticotropic hormone (ACTH) immunohistochemistry.