Endocrine Abstracts

Background: In contrast to females with prolactinoma, male patients usually present with a history of long-standing hypogonadism and a macroadenoma on MRI-scan. Data is scarce about the effect of hypogonadism on bone health in these patients. We, therefore, investigated retrospectively the cohort of male patients with prolactinoma at our institution.

Patients and methods: Between 1983 and 2007, the chards of 44 male patients with prolactinoma were reviewed. Clinical, biochemical characteristics and tumour size were assessed at baseline and at last follow-up. Qualitatively bone density assessment (i.e. osteopenia, osteoporosis) was registered.

Results: The mean age at diagnosis was 47.4 (15.3), years, mean (S.D.), the leading symptoms were loss of libido in 68% and erectile dysfunction in 50% of the patients. Mean BMI at diagnosis was 28.7 (4.5) kg/m². Prolactin levels were 1978.5 (779.8–4890.3), μg/l, median (IQR), and MRI scan showed macro- meso- and microadenoma in 77, 5 and 18% respectively. Bone density revealed pathological bone density in 25% of the patients. Nine percent of all patients were diagnosed with osteoporosis. Therapeutical strategy included primary operation in 32% and dopamine agonists in 68% of the patients.

At last follow-up the mean age was 54.0 (15.6), years, loss of libido and erectile dysfunction was reported in 20 and 15% of the patients, respectively. Mean BMI tended to decrease from 28.7 (4.5) to 28.0 (4.4) kg/m² (P=0.08). Prolactin concentration significantly decreased to 13.8 (7.0–27.1) μg/l, median (IQR; P<0.001) and was within normal range in 80% of the patients. The control of hyperprolactinaemia required Dopaminagonist therapy in 75% of the patients (three patients with microadenoma, 2 patients with mesoadenoma, 28 patients with macroadenoma). Fifty five percent of all patients needed Testosterone therapy, 2/3 of them had macroadenomas. Biphosphonate and/or Vitamin D and Calcium was prescribed in 25% of the patients. No significant differences in clinical outcome and need for dopamine agonist or testosterone therapy were observed according to the therapeutical strategy (i.e. primary surgery vs primary medical therapy).

Conclusion: (1) Based on these results assessment of bone densitometry in male patients with prolactinoma can be recommended. (2) The tendency for a decrease of BMI following therapy remains to be confirmed. (3) A surgical procedure besides the classical indication (i.e. intolerance of dopamine agonists and non-responder) cannot be recommended in male patients with macroprolactinoma. (4) A substantial number of patients had testosterone replacement therapy at last follow-up.