Do nothing but observe microprolactinomas: when and how to replace sex hormones?

Hyperprolactinemia is associated with suppression of the hypothalamic- pituitary-gonadal axis and consequent hypogonadism, manifesting loss of libido, infertility and osteoporosis long-term in both male and female patients, with associated menstrual irregularities, amenorrhea and galactorrhea in women and erectile dysfunction in men. The primary goals of therapy in patients harboring prolactinoma are control of tumor size and normalization of serum PRL, with restoration of gonadal and sexual function and fertility. Clinical manifestations of hypogonadism have variable consequences depending on the age and sex of the patient and desire for fertility. Careful consideration of clinical consequences of hyperprolactinemia in relation to age and sex should help guide therapeutic decision making. Another important consideration in attaining our treatment goals in patients harboring microprolactinomas, is the observation that greater than 90% of microprolactinomas do not enlarge, when followed for 10 years. Treatment options for the management of microprolactinomas include observation alone, with monitoring of serum prolactin levels every 6-12 months, vs initiation of dopamine agonist therapy vs gonadal steroid hormone replacement (using the oral contraceptive or other combination estrogen and progesterone replacement regimens in females or testosterone replacement therapy in males). In the present review, current data related to clinical consequences of microprolactinomas and treatment outcomes at different stages in the lifespan are reviewed, with a suggested algorithm as to whether to treat or not, and an appropriate therapeutic regimen to institute.