Relapse of hyperprolactinemia after transsphenoidal surgery for microprolactinoma: lessons from long-term follow-up

The long-term results of transsphenoidal surgery for microprolactinoma, with particular reference to the question of permanence of relapse of hyperprolactinemia after biochemical cure, are examined. Patients whose operations were performed in the city of Glasgow, Scotland, by one neurosurgeon (GMT) have been followed up for between 15 and 21 years after surgery was performed. Of a cohort of 44 patients with confirmed microprolactinoma at the time of surgery, 8 patients (18.2%) who experienced recurrent hyperprolactinemia postoperatively continued to be monitored. Selective hypophysectomy resulted in normal prolactin levels in all patients initially. Relapse occurred at 2 to 10 years (mean, 5.3 yr) postoperatively, but was permanent in only two patients (4.5%). Of the remaining six patients (13.6%), four (9.1%) became normoprolactinemic after 6 or 7 years' recurrence, and two (4.5%) are now only marginally hyperprolactinemic (prolactin >500 but