treatment of macroprolactinomas

Last reviewed 01/2018

• dopamine agonist therapy is the treatment of choice (over 70% of macroprolactinomas are sensitive to dopamine agonist therapy)
  • pharmacological management with dopamine agonist is proposed as first-line treatment even in giant prolactinomas as it has been shown to be effective in reducing PRL levels and inducing significant tumor shrinkage (2)
• surgical chiasmal decompression is required to prevent irreversible optic nerve damage, if there is no response to six weeks dopamine agonist treatment (1)
  • surgical intervention is less effective compared to medical therapy and may be performed for rapid optic decompression and visual improvement or it may be selected for patients resistant to dopamine antagonist therapy
  • total surgical removal of giant prolactinomas that expand into different directions in the supra-, para- and infrasellar areas is very difficult or even impossible

Notes:

• macroprolactinomas occur less frequently than microadenomas and their incidence is higher in men compared to women
  • giant prolactinomas, a rare subtype of macroadenomas, are characterized by large size (over 4 cm), very high prolactin levels (more than 1000 ng/ml) and invasive growth and are thus the most difficult to treat

Reference:

• Prescribers' Journal 2000; 40 (2):86-92.
• Gillam MP, Molitch ME, Lombardi G, Colao A. Advances in the treatment of prolactinomas. Endocr Rev 2006; 27: 485-534.
• Melmed S, Casanueva FF, Hoffman AR, et al.Diagnosis and treatment of hyperprolactinemia: an Endocrine Society clinical practice guideline. J Clin Endocrinol Metab 2011;96: 273-288.