Patients with macroprolactinomas had significantly higher baseline PRL levels than those with microprolactinomas (median 722.7 ng/mL, IQR 391.8 – 1000 vs 96.3 ng/mL, IQR 68.5 – 145.6, p < 0.0001), and accordingly required higher starting doses of DA (median 1.0 mg/week, IQR 1.0 – 3.0 vs 0.5 mg/week, IQR 0.5 – 1.0, p < 0.0001). This evidence concerns the gene PRL and Microprolactinoma.