JOHNS HOPKINS
Prolactinoma
Radiosurgery

Prolactinomas

Prolactinomas cause specific clinical syndromes.

Prolactinomas have specific signs and symptoms that are primarily related to the endocrinopathies produced by hypersecretion.

• PROLACTINOMAS account for approximately 40% of pituitary tumors. Patients with these tumors have benefited from medical treatment with dopamine agonists, such as bromocriptine, which reduce tumor volume and return prolactin (PRL) secretion to normal concentrations in 80% of cases. However, surgery is widely used to avoid the side effects of this treatment and to handle bromocriptine-resistant prolactinomas. Advances in pituitary surgery involving use of the rhinoseptal route have led to a definitive cure in 62 to 89% of patients with microprolactinomas. However, there has been no early and reliable predictive index to ascertain whether surgery has been successful. Some factors, such as high preoperative concentrations of PRL, the presence of an invasive tumor, and the age of the patient at the time of surgery, have been reported to be factors in surgical failure.
  
  
• Dopamine agonists stimulate pituitary dopamine (D2) receptors, which results in the suppression of prolactin secretion. In most patients with prolactin-producing pituitary adenoma, dopamine agonists decrease blood prolactin levels, improve the clinical symptoms, and cause a marked tumor shrinkage accompanied by normalization of any visual defects. Some patients with prolactin-producing pituitary adenoma fail to respond to dopamine agonist medication. The frequency and causes of this resistance to dopamine agonist therapy are not known.
  
  

Microsurgical resection of prolactinomas can be done via two approaches.

Microsurgical resection of prolactinomas can be done via two approaches.

• The transphenoidal approach allows resection of small to medium-sized prolactinomas. The risks of surgery include CSF (spinal fluid leak) and meningitis. The rates of these complications are low, however.
  
  
• The pterional approach allows greater visualization and exposure of larger prolactinomas.

Stereotactic Radiosurgery offers non-invasive control of newly diagnosed or recurrent prolactinomas.

Stereotactic Radiosurgery allows specific irradiation of only the prolactinoma. Narrow beams of radiation specifically target only the prolactinoma. The normal brain is spared and does not receive significant exposure. For treatment there are no "pins" placed in the scalp as with single fraction techniques. The treatment results in control of the majority of prolactinomas and their endocrinological sequelae. Stereotactic radiosurgery may be particularly suitable for functional pituitary adenomas (prolactinomas) to reduce the level of hormonal secretion. For recurrent pituitary adenomas after conventional surgery and radiation, stereotactic radiosurgery is particularly appropriate, allowing sparing of the optic nerves with delivery of high radiation dose to the recurrent prolactinoms.

The patient information may be submitted.

Stereotactic Radiosurgery offers specific, local treatment to the prolactinoma with sparing of surrounding normal tissues.