A 37-year-old woman comes to the office with a 7-month history of galactorrhea and amenorrhea. She has also had worsening vaginal dryness, but no headaches or visual symptoms. The patient's medical history is unremarkable, and she does not use tobacco, alcohol, or illicit drugs. She is married, has 2 children, and remarks that her family is "complete." The patient's husband has undergone vasectomy. Her temperature is 36.7 C (98 F), blood pressure is 120/80 mm Hg, pulse is 72/min, and respirations are 14/min. Visual field testing is normal. Pregnancy test is negative, serum prolactin level is 150 ng/mL (154 ng/mL on repeat measurement), and thyrotropin (TSH) and serum creatinine are normal. MRI of the pituitary gland reveals a 6-mm hypointense lesion, as shown in the image below, which is consistent with a pituitary adenoma. Which of the following is the most appropriate next step in management of this patient?

Question

A 37-year-old woman comes to the office with a 7-month history of galactorrhea and amenorrhea.  She has also had worsening vaginal dryness, but no headaches or visual symptoms.  The patient's medical history is unremarkable, and she does not use tobacco, alcohol, or illicit drugs.  She is married, has 2 children, and remarks that her family is "complete."  The patient's husband has undergone vasectomy.  Her temperature is 36.7 C (98 F), blood pressure is 120/80 mm Hg, pulse is 72/min, and respirations are 14/min.  Visual field testing is normal.  Pregnancy test is negative, serum prolactin level is 150 ng/mL (154 ng/mL on repeat measurement), and thyrotropin (TSH) and serum creatinine are normal.  MRI of the pituitary gland reveals a 6-mm hypointense lesion, as shown in the image below, which is consistent with a pituitary adenoma.  Which of the following is the most appropriate next step in management of this patient?

Quizplus · Accepted Answer

11ec25c8_d3b6_9da1_bc81_17a02947627d_MD0003_00 This patient has a pituitary microadenoma (<10 mm) associated with galactorrhea and symptoms of low estrogen (eg, amenorrhea, vaginal dryness). Any mass lesion in the pituitary gland can cause a mild elevation in prolactin due to disruption of the normal inhibitory dopaminergic regulation of prolactin secretion. However, significant elevations in the prolactin level (eg, serum prolactin level >200 ng/mL or repeat level >100 ng/mL) suggest a prolactin-secreting tumor (prolactinoma). Elevated prolactin levels suppress gonadotropin-releasing hormone, LH, and estradiol, leading to oligo-amenorrhea in premenopausal females. Men and postmenopausal women often have minimal early symptoms and are more likely to seek evaluation when a large tumor (>1 cm, macroadenoma) causes mass-effect symptoms (eg, headache, visual field defects). Asymptomatic patients with an incidental finding of a microprolactinoma may be observed over time (Choice A). Patients with macroprolactinomas or symptomatic tumors of any size (as with this patient) should be treated with dopaminergic agonists (eg, cabergoline, bromocriptine), which can normalize prolactin levels and reduce tumor size. Patients who fail to respond or who have very large tumors (>3 cm) should be referred for transsphenoidal resection (Choice C). (Choice B) Patients with residual prolactinoma tissue following resection can be considered for radiotherapy. However, the response to radiotherapy is generally delayed, and radiotherapy may lead to panhypopituitarism. (Choice E) Estrogen replacement therapy may be given to reduce the risk of osteoporosis in hypoestrogenic women with microprolactinoma who do not tolerate dopamine agonists. However, estrogen does not reduce tumor size. Educational objective: Patients with a macroprolactinoma (>1 cm) or a symptomatic prolactinoma should be treated with dopaminergic agonists (eg, cabergoline, bromocriptine), which can lower prolactin levels and reduce tumor size. References: Diagnosis and treatment of hyperprolactinemia: An Endocrine Society clinical practice guideline. (http://www.ncbi.nlm.nih.gov/pubmed/21296991)

A 37-Year-Old Woman Comes to the Office with a 7-Month