Time Course of Resolution of Hyperprolactinemia After Transsphenoidal Surgery Among Patients Presenting with Pituitary Stalk Compression.
BACKGROUND
Primary lactotroph disinhibition, or stalk effect, occurs when mechanical compression of the pituitary stalk disrupts the tonic inhibition by dopamine released by the hypothalamus. The resolution of pituitary stalk effect-related hyperprolactinemia postoperatively has not been studied in a large cohort of patients. We performed a retrospective review to investigate the time course of recovery of lactotroph disinhibition after transsphenoidal surgery.


METHODS
Medical records were retrospectively reviewed for all patients undergoing transsphenoidal surgery with the senior author from April 2008 to November 2014.


RESULTS
Of 556 pituitary adenomas, 289 (52.0%) were eliminated: 77 (13.9%) had an immunohistochemically confirmed prolactinoma, 119 (21.4%) patients had previous surgery, 93 (16.7%) had incomplete medical records, leaving 267 patients (48.0%) for final analysis. Of these patients, 72 (27.0%) had increased serum prolactin levels (≥23.3 ng/mL), suggestive of pituitary stalk effect (maximum prolactin level = 148.0 ng/mL). Patients with stalk effect were more likely than those with normal serum prolactin levels to present with menstrual dysfunction (29.7% vs. 19.4%; P < 0.01) and galactorrhea (11.1% vs. 2.1%; P < 0.01). Patients with lactotroph disinhibition were more likely to harbor macroadenomas than were patients who did not show lactotroph disinhibition (81.9% vs. 70.2%; P = 0.06). Among patients with increased preoperative prolactin, 77.8% experienced normalization of serum prolactin postoperatively, galactorrhea improved in 100%, sexual dysfunction resolved in 66.6%, and menstrual dysfunction among premenopausal females normalized in 73.3% at last follow-up (mean, 5.35 years; range, 0.1-10 years).


CONCLUSIONS
Transsphenoidal surgery can provide durable normalization of serum prolactin levels and related symptoms caused by pituitary stalk compression-related lactotroph disinhibition.
Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA. Electronic address: hzaidi@partners.org.
Hasan A
HA
Zaidi
Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA.
David J
DJ
Cote
Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA.
Joseph P
JP
Castlen
Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA.
William T
WT
Burke
Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA.
Yong-Hui
YH
Liu
Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA.
Timothy R
TR
Smith
Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA.
Edward R
ER
Laws
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015331:Cohort Studies; D005260:Female; D005687:Galactorrhea / Q000209:etiology / Q000601:surgery; D006801:Humans; D006966:Hyperprolactinemia / Q000097:blood / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D019635:Neurosurgical Procedures / Q000379:methods*; D009666:Nose / Q000601:surgery; D010902:Pituitary Gland / Q000601:surgery*; D010911:Pituitary Neoplasms / Q000150:complications* / Q000601:surgery; D011247:Pregnancy; D011388:Prolactin / Q000097:blood; D015175:Prolactinoma / Q000150:complications* / Q000601:surgery; D012086:Reoperation / Q000379:methods; D013100:Sphenoid Bone / Q000601:surgery; D016896:Treatment Outcome; D055815:Young Adult
D011388:Prolactin
Dopamine; Prolactin; Stalk effect; Transsphenoidal surgery