Pituitary Adenoma

Summary

Pituitary adenomas are a type of benign brain tumor most commonly found in adults. These tumours are usually associated with MEN1, a condition characterized by multiple endocrine tumors in the pituitary, parathyroid, and pancreas. 

Due to mass effect, pituitary tumours cause headaches and bitemporal hemianopsia, a loss of vision in the outer halves of both visual fields. Pituitary adenomas also cause a variety of hormonal abnormalities. In particular, hyperfunctioning pituitary adenomas produce excess hormones, which are usually prolactin, growth hormone, or ACTH. Finally, pituitary apoplexy or hemorrhage is a serious complication of pituitary adenomas. 

Key Points

• Pituitary Adenoma
  • Characteristics
    • Benign tumor of the pituitary gland
  • Presentation
    • Generally affects adults
    • Associated with Multiple Endocrine Neoplasia 1
    • Bitemporal hemianopia
    • Headaches
    • Hormonal abnormalities
      • Due to functional (hormone-producing) tumors or destruction of functional pituitary gland
      • Prolactinoma (prolactin-secreting) is most common
      • Cushing Disease (ACTH-secreting)
      • Acromegaly (GH-secreting)
      • Goiter (TSH-secreting)
      • Hypergonadism (FSH/LH-secreting)
      • Hypopituitarism
  • Complications
    • Pituitary Apoplexy (hemorrhage)
  • Treatment
    • Multimodal treatment
      • Surgical resection to remove tumor
      • Medical therapies to counteract hormone abnormalities