Patient will present as → a 31-year-old woman who complains of irregular, infrequent menstrual periods. On further questioning, she complains of headaches, fatigue, and breast discharge. She takes ibuprofen only occasionally. The serum prolactin level is 380 μg per L.
Pituitary adenomas are benign tumors of the anterior pituitary that derive from one of the five types of pituitary hormone-producing cells
- Common presentations associated with pituitary adenoma (may involve multiple endocrine abnormalities)
- Pituitary adenomas < 1 centimeter are called microadenomas, whereas those > 1 centimeter are called macroadenomas
Classification of Pituitary Adenomas | ||
Tumor Type | Secretory Product(s) | Relative Frequency (%) |
Prolactinoma (Galactorrhea)
|
↑ Prolactin | 50 |
Somatotroph adenoma (acromegaly & gigantism) | ↑ Growth Hormone (GH) | 10 |
Corticotroph adenoma (Cushing's disease) | ↑ ACTH | 5 |
Thyrotroph adenoma (Hyperthyroidism) | ↑ TSH | 1 |
Gonadotroph adenoma | ↑ LH ↑ FSH | 3 |
Non-Secreting Adenoma | α alpha -subunit | 34 |
Diagnosis is made by MRI - look for sellar lesions/tumors
- Endocrine studies: Prolactin, GH, ACTH, TSH, FSH, LH
Treatment is often surgical
- Transsphenoidal surgery: management of choice for removal of ACTIVE or compressive tumors
- Medical management is the first line for prolactinomas - Dopamine inhibits prolactin release - Cabergoline or Bromocrpitine (dopamine acgonists)
- Acromegaly: TSS + Bromocriptine (dopamine decreases GH production)
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Prolactinoma is a prolactin secreting tumor of the pituitary gland. This tumor is the most common adenoma of the pituitary gland. These tumors are benign but can cause symptoms due to elevated prolactin levels in the blood or by compression of nearby structures. Prolactin is the hormone that stimulates the breast to produce breast milk. Therefore, elevated prolactin levels are usually seen during pregnancy and after childbirth. Pathologic secretion of prolactin from prolactinomas can cause galactorrhea in women although rare in men because of insufficient breast tissue. Prolactin also inhibits the release of gonadotropin releasing hormone. Normally, GnRH stimulates the release of FSH and LH from the anterior pituitary, which plays an important role in the synthesis of sex hormones. Increased prolactin can therefore cause decreased levels of sex hormone in men and women, leading to impotence and amenorrhea, respectively. Enlargement of the tumor can lead to compression of the optic chiasm resulting in bitemporal hemianopia. Dopamine physiologically suppresses prolactin secretion and is used in the treatment of prolactinomas.
Play Video + QuizQuestion 1 |
anorexia nervosa | |
stress | |
pregnancy | |
prolactinoma |
Question 2 |
estrogen | |
progesterone | |
LH | |
FSH | |
prolactin |
Question 3 |
transsphenoidal resection | |
bromocriptine | |
clomiphene | |
lithium | |
thyroxine |
List |
References: Merck Manual · UpToDate