Prolactinomas account for a substantial proportion of pituitary adenomas and commonly affect women of reproductive age, although men often present with larger tumors and delayed diagnosis. Elevated prolactin levels lead to menstrual irregularities, infertility, galactorrhea, sexual dysfunction, and decreased bone density. In larger adenomas, compression of adjacent structures may result in headaches and visual disturbances. Dopamine agonists act by stimulating dopamine D2 receptors on lactotroph cells, thereby inhibiting prolactin secretion and suppressing tumor growth. Despite the widespread use of these medications, treatment resistance, recurrence, and long-term safety remain important clinical concerns. Evaluating the current effectiveness of dopamine agonists is essential for optimizing therapeutic strategies and improving patient outcomes.
The aim of the study was to assess the current efficacy of dopamine agonists in the treatment of prolactin-secreting pituitary adenomas and to evaluate their impact on hormonal control, tumor regression, clinical symptoms, and treatment tolerability.
The study included 90 patients diagnosed with prolactin-secreting pituitary adenomas, including both microadenomas and macroadenomas. Patients underwent comprehensive endocrinological evaluation, serum prolactin measurement, magnetic resonance imaging (MRI) of the pituitary gland, and ophthalmological assessment when indicated. Patients received treatment with dopamine agonists, primarily cabergoline or bromocriptine, according to established clinical protocols. Follow-up evaluations included monitoring of prolactin levels, tumor size changes on MRI, restoration of reproductive function, symptom improvement, and adverse effects associated with therapy. Statistical analysis was performed to compare treatment outcomes between therapeutic groups.
Normalization of serum prolactin levels was achieved in approximately 82% of patients treated with cabergoline and 65% of patients receiving bromocriptine. Significant tumor shrinkage was observed in most patients, particularly among those with microadenomas. Cabergoline demonstrated superior effectiveness in reducing tumor volume and improving clinical symptoms, including menstrual function restoration and reduction of galactorrhea. Patients treated with cabergoline also experienced fewer gastrointestinal and neurological side effects compared to bromocriptine. Resistant prolactinomas were identified in a small percentage of patients, requiring higher medication doses or combined therapeutic approaches. Long-term therapy contributed to stabilization of endocrine function and reduction of recurrence rates.
Dopamine agonists remain highly effective in the management of prolactin-secreting pituitary adenomas. Cabergoline demonstrates greater efficacy, improved tolerability, and better patient compliance compared to bromocriptine. Early diagnosis and individualized treatment strategies contribute to successful hormonal control, tumor regression, and restoration of reproductive and neurological function. Continued monitoring and long-term follow-up are essential for identifying resistant cases and preventing disease recurrence.
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