Hyperprolactinemia caused by extra-pituitary prolactin secretion: a systematic review

Area of Science:

• Endocrinology
• Oncology
• Neurosurgery

Background:

• Hyperprolactinemia is commonly caused by pituitary adenomas.
• Ectopic prolactin secretion from extra-pituitary sources is a rare but significant differential diagnosis.

Purpose of the Study:

• To summarize clinical and pathological characteristics of hyperprolactinemia due to ectopic prolactin secretion.
• To analyze treatment strategies and therapeutic outcomes for these rare cases.

Main Methods:

• Systematic literature search of three databases using terms related to ectopic prolactin secretion.
• Inclusion of 52 case reports of patients with extra-pituitary prolactin-secreting tumors.
• Analysis of patient demographics, prolactin levels, symptoms, histology, and treatment responses.

Main Results:

• Ectopic prolactin-secreting sites included ectopic pituitary adenomas and non-pituitary-derived extracranial lesions.
• Symptoms varied, with intracranial mass effect common in ectopic pituitary adenomas and galactorrhea/amenorrhea in non-pituitary lesions.
• Dopamine agonists were effective for ectopic pituitary adenomas, but surgery yielded better outcomes for non-pituitary lesions, which were often resistant to medication.

Conclusions:

• Hyperprolactinemia from ectopic prolactin secretion requires consideration in unexplained cases.
• Ectopic pituitary adenomas and non-pituitary lesions present differently and respond variably to treatments.
• Surgical intervention is often necessary for non-pituitary ectopic prolactin-secreting lesions.