What is the recommended first-line treatment for a patient diagnosed with a prolactinoma, and how should I monitor their response?

First-line treatment for prolactinoma: The recommended first-line treatment for a patient diagnosed with a prolactinoma is medical therapy with dopamine agonists, typically cabergoline or bromocriptine. These medications reduce prolactin secretion and tumour size effectively.

Monitoring response to treatment: The patient's response to treatment should be monitored by regular measurement of serum prolactin levels to assess biochemical response and by periodic MRI scans to evaluate tumour size reduction. Clinical symptoms such as restoration of gonadal function and resolution of mass effects should also be assessed. Long-term follow-up is necessary to detect recurrence or resistance to therapy.