Prolactinoma diagnosis: Clinical, biochemical, and radiological considerations.

Diagnosing a prolactinoma is often straightforward if the tests are carried out in a systematic manner, taking into account potential sources of error. Prolactin testing should be restricted to patients with a clear indication for further investigation. Pre-analytical and analytical challenges may lead to false positive or false negative test results. A variety of other causes of hyperprolactinemia should be considered before proceeding to imaging of the sellar region to detect an underlying prolactinoma. Non-tumoral hyperprolactinemia should be considered in patients with discordant symptoms, biochemical tests and imaging.