Endoscopic Transnasal Approach for Microprolactinomas with Experience of 105 Cases in a Single Center: Paradigmal Shift for Conventional Medical Therapy.

Objective: The classically recommended first-line therapy for microprolactinomas is medical therapy. In the presence of drug resistance and intolerance after the use of dopamine agonists or when the patients prefer surgery instead of medication, surgical treatment is considered as second-line treatment. The high hormonal remission and low complication rates after surgery for microprolactinomas suggest that the surgical outcome of endoscopic surgeries may be better than medical therapy in well-selected patients. This study reports a large series of patients with microprolactinoma treated by endoscopic transnasal approach and evaluates the efficiency of surgical treatment.

Methods: Our study is a retrospective cohort analysis of patients with microprolactinoma operated on by an endoscopic transnasal approach between August 1997 and February 2022 by an experienced pituitary surgeon in a single tertiary center. Inclusion criteria for microprolactinoma were based on increased prolactin levels, microadenoma (<10 mm in diameter) on pituitary magnetic resonance imaging, and histopathologically verified lactotroph adenoma.

Results: The mean follow-up was 74.90 months (range, 6-207). The postoperative day 1 remission rate was 85.7% and the long-term remission rate was 74.3%. The long-term remission rates of the patients in the preference group were significantly higher than those of the patients in the resistant or intolerance group (P = 0.002). Patients who used dopamine agonists for more than 3 years had a lower remission rate compared with patients who used dopamine agonists for a shorter period or who did not use it (P = 0.01). The surgical complication rate was 4.76%.

Conclusions: According to our findings, endoscopic transnasal surgery performed by an experienced neurosurgeon in well-selected patients with microprolactinoma can be offered with cure rates superior to medical therapy and may be an alternative first-line treatment option to dopamine agonists.