Long-term results of cabergoline therapy for macroprolactinomas and analyses of factors associated with remission after withdrawal.

ABSTRACT

OBJECTIVE: Withdrawal of cabergoline is generally challenging, especially in patients with large or invasive macroprolactinomas. Therefore, we aimed to assess long-term results of cabergoline therapy for macroprolactinomas and remission achievement results after withdrawal in patients with macroprolactinomas. We also investigated clinical characteristics and factors related to remission after withdrawal. METHODS: This was an institutional review board-approved retrospective analysis. We studied 46 macroprolactinoma patients who had taken cabergoline during the period from 2003 through 2013. Administration of cabergoline was maintained for 5 years before withdrawal. RESULTS: Median follow-up after the initiation of cabergoline therapy was 54·3 (range 5·3 to 137·2) months. Recurrences of hyperprolactinaemia were observed in 3 of 11 (27%) postwithdrawal patients at a median time of 3·0 (range; 2·9-11·2) months, indicating that a high percentage (73%) maintained remission for at least 12 months after cabergoline cessation. Factors significantly associated with remission were analysed in 21 patients receiving long-term cabergoline administration. On multivariate analysis, the absence of cavernous sinus invasion on pretreatment MRI (≥3/4 tumour encasement of the intracavernous internal carotid artery) (HR; 21·94, 95% CI; 2·06-1071·0, P = 0·006), initial PRL <132·7 ng/ml (HR; 8·28, 95% CI; 1·24-199·6, P = 0·03) and nadir PRL <1·9 ng/ml during cabergoline therapy (HR; 5·14, 95% CI; 1·10-39·02, P = 0·04) showed statistically significant correlations with remission after withdrawal. CONCLUSIONS: Cabergoline therapy can achieve a high percentage (73% in this series) of remission maintenance for at least 12 months after cessation of a 5-year course of therapy, even in patients with macroprolactinomas. The absence of cavernous sinus invasion, serum PRL level lower than 132·7 ng/ml before cabergoline therapy or nadir serum PRL below 1·9 ng/ml were related to more frequent remission after withdrawal of cabergoline in patients receiving this medication for 5 years.