Endocrine Abstracts

Objectives

Male prolactinoma patients mostly have hypogonadotropic symptoms. While treatment with dopamine agonists (DAs; such as bromocriptine or cabergoline) leads to recovery of sexual glands, it can lead to impulsive control disorders as an undesirable side effect. The aim of this retrospective study is to determine the level of testosterone that eliminates symptoms, provides fertility and does not cause this undesirable side effect regardless of prolactin (PRL) level in macroprolactinomas with long-term follow-up.

Material and Methods

Twenty-seven male patients with macroprolactinoma followed in outpatient Pituitary Clinic were included to the study. There were 16 macro (≥ 1–2.8 cm), 7 large macro (≥ 2.9–3.9 cm) and 4 giant (≥ 4 cm) adenomas. From medical records PRL, LH, FSH, Testosterone (T) were evaluated and a timeline was created to analyze the progress regarding symptoms of hypogonadism and infertility. At each visit, their answers to hypogonadism symptoms and fertility questions were evaluated. PRL and T levels in the period when they were asymptomatic and fertile were recorded. Fertility-induced T levels were compared with age-matched thirty-three controls. Patients with children prior to admission were excluded from fertility statistical analysis.

Results

The mean age of patients was 38.8 ± 11.8 years, and 41.6 ± 10.2 years in the controls. The average delay in diagnosis was 4.3 years. Mean PRL, basal tumor diameter and shrinkage were 2846 ± 3415 ng/ml, 27.2 ± 10.2 mm and 63.4%, respectively. Basal T levels were 1.6 ± 1.0 ng/ml for patients and 4.4 ± 1.5 ng/ml for controls (P < 0.001). Mean T level in asymptomatic period was significantly lower than controls (3.2 ± 0.4 ng/ml vs. 4.4 ± 1.5 ng/ml, respectively, P = 0.002), and at this time mean PRL was slightly elevated than normal as 27.2 ng/ml. Mean maximum dose of bromocriptine and cabergoline were 11.1 ± 5.1 mg/daily and 1.7 ± 0.6 mg/weekly, respectively. The patients were followed up for an average of 8.3 ± 4.8 years. Fertility was achieved in 6 of the patients who desired fertility, and there was no difference between the T levels of these patients and the controls (3.7 ± 0.8 ng/ml vs. 4.4 ± 1.5 ng/ml, P = 0.38). When fertility was achieved mean PRL level was 26.9 ± 23 ng/ml. The highest T levels of the patients under therapy was not significantly different from controls (4.9 ± 1.6 ng/ml vs. 4.4 ± 1.5 ng/ml, respectively). Mean PRL level accompanying these T levels was 12.1 ± 15.2 ng/Ml.

Conclusion

The slightly elevated PRL should not be taken into account in these patients under treatment, when symptoms disappear, or fertility is restored. Therefore, patients should be carefully questioned in terms of their complaints at each visit and the dose of DA should not be increased unnecessarily to avoid possible adverse serious side effects.