Predictors of the Outcome of Transsphenoidal Surgery for Prolactin-Secreting Pituitary Adenomas*

Sixty-seven women who underwent transsphenoidal resection of PRL-secreting pituitary adenomas between 1976 and 1979 were separated into categories according to the manner of their clinical presentation. Forty-one had oral contraceptive-related onset of amenorrhea-galactorrhea, 5 had pregnancy-related onset of amenorrhea-galactorrhea, 5 had primary amenorrhea, and 16 had the spontaneous onset of amenorrhea-galactorrhea unrelated to estrogen use. Surgical success, defined as the resumption of regular menses and normalization of serum PRL concentration, was achieved in 54% of those with estrogen-related onset of amenorrhea-galactorrhea compared with 19% in the other group. The analysis of multiple preoperative features, including clinical classification, age, preoperative PRL concentration, and duration of amenorrhea-galactorrhea by logistic regression, demonstrated that the clinical classification was the most important factor in predicting the outcome of transsphenoidal surgery. It should be a prime consideration in the selection of therapy for PRL-secreting adenomas.