The outcome of 24 months of cabergoline treatment on prolactin (PRL) normalization, tumor shrinkage, restoration of pituitary function, and semen alterations was prospectively investigated in 41 men with macro- (age 17-70 yr) and 10 with microprolactinoma (age 18-53 yr). Fifty-one age-matched men served as controls for semen analysis. At study entry, of the 41 patients with macroprolactinoma, 17 (41.4%) had visual field defects, 14 (34.1%) had headache, eight (19.5%) had galactorrhea, 22 (53.6%) had hypopituitarism apart from hypogonadism, and 30 (73.2%) had low testosterone levels; of the 10 patients with microprolactinoma, none had visual field defects, galactorrhea, or hypopituitarism apart from hypogonadism, two had headache (20%), and five had low testosterone levels (50%; P = 0.3). After 24 months of therapy, 1) PRL levels normalized in 31 patients with macro- (75.6%) and in eight with microprolactinoma (80%; P = 0.9), and galactorrhea disappeared in all patients; 2) maximal tumor diameter reduced by 73.7 +/- 22.6% in macro- and 72.8 +/- 28.3% in microprolactinomas (P = 0.91), and 15 macro- (30%) and seven microprolactinomas (46.7%; P = 0.37) disappeared; 3) visual field defects disappeared in 15 (75%) patients with macroprolactinoma, and headache disappeared in 15 (83%) patients with macro- and in one with microprolactinoma (50%); 4) GH secretion recovered in 62.5% and ACTH secretion in 60% of patients; 5) testosterone levels normalized in 25 patients with macro- (60.9%) and six with microprolactinoma (60%) after 6 months, and 20 patients required testosterone or gonadotropin replacement (in 14 or six patients, respectively); and 6) sperm volume and count normalized in all patients who normalized testosterone levels, whereas motility normalized in more than 80%. Cabergoline therapy was well tolerated; only 4.5% of patients had side effects at high doses. These data demonstrate that cabergoline treatment is as effective and safe in men as in women with prolactinoma and can be successfully used as primary therapy even in men bearing large macroprolactinomas.

The finding that blood methaemoglobin and Pb were inversely correlated with sperm parameters indicates that nitrogen oxide and Pb adversely affect semen quality.

Hyperprolactinemia induces hypogonadism by inhibiting gonadotropin-releasing hormone pulsatile secretion and, consequently, follicle-stimulating hormone, luteinizing hormone, and testosterone pulsatility. This leads to spermatogenic arrest, impaired motility, and sperm quality and results in morphologic alterations of the testes similar to those observed in prepubertal testes. Men with hyperprolactinemia present more frequently with a macroadenoma than a microadenoma. Symptoms directly related to hypogonadism are prevalent. In men hypogonadism leads to impaired libido, erectile dysfunction, diminished ejaculate volume, and oligospermia. It is present in 16% of patients with erectile dysfunction and in approx 11% of men with oligospermia. Treatment with bromocriptine or cabergoline (CAB) is effective in men with prolactinomas, with a response that is in general comparable to treatment in women. Seminal fluid abnormalities rapidly improve with CAB treatment, while other dopaminergic compounds require longer periods of treatment. Moreover, to improve gonadal function in men, the integrity of the hypothalamic-pituitary-gonadal axis is necessary. New promising data indicate that a substantial proportion of patients with either micro- or macroprolactinoma do not present hyperprolactinemia after long-term withdrawal from CAB. Whether this corresponds to a definitive cure is still unknown, but treatment withdrawal should be attempted in patients achieving normalization of prolactin levels and disappearance of tumor mass to investigate this issue.

This open longitudinal study investigated the prevalence of depressed sexual potency by monitoring erectile dysfunction using nocturnal penile tumescence (NPT) in 51 consecutive men with hyperprolactinemia (41 macroprolactinomas and 10 microprolactinomas) and evaluated potential reversibility of sexual failure after 6 months of treatment with cabergoline. Fifty-one healthy men served as controls. Compared with controls, the patients with either micro- or macroprolactinoma had low testosterone levels with severe alterations of erectile function. Testosterone deficiency was present in 73.2% of macro- and 50% of microprolactinomas; reduced libido and sexual potency were referred by 53.6% of macroprolactinomas, 50% of microprolactinomas, and none of controls. Fewer than three erectile events per night by NPT were found in 96.7% of patients and 13.7% of controls (P < 0.0001). After 6 months of cabergoline treatment, prolactin levels normalized in 74.5% of patients: 73.2% of macroprolactinomas and 80% of microprolactinomas. Testosterone levels normalized in 68.6% of patients, whereas NPT normalized in 60.6% of patients who had normalized prolactin levels and in 7.7% of patients who did not. In conclusion, at study entry, 50% of the patients complained of sexual disturbances, 96.7% of whom had an impairment of erectile events per night compared with 13.7% of controls. Six months of treatment with cabergoline normalized testosterone levels in most cases, thus restoring and maintaining during treatment the capability of normal sexual activity in hyperprolactinemic males.

This study evaluated the effects of chronic treatment with cabergoline (CAB), a new, potent and longlasting ergoline-derived dopamine agonist, on seminal¯uid parameters and sexual and gonadal function in hyperprolactinemic males in comparison with the effect of bromocriptine (BRC) treatment.Seventeen males with macroprolactinoma were treated with CAB at a dose of 0.5±1.5 mg/week (n 7), or BRC at a dose of 5±15 mg/day (n 10) for 6 months. Baseline prolactin (PRL) was 925.7 6 522.6 mg/l in the CAB-treated group and 1059.4 6 297.6 mg/l in the BRC-treated group. All the patients suffered from libido impairment, ten from reduced sexual potency, and six had infertility. In ®ve patients provocative bilateral galactorrhea was found.Seminal¯uid analysis, functional seminal tests and penis rigidity and tumescence, measured by nocturnal penile tumescence (NPT) using Rigiscan equipment, were assessed before and after 1, 3 and 6 months of CAB or BRC treatment. Hormone pro®les were assessed before and after 15, 30, 60, 90 and 180 days of both treatments.Before treatment, all patients had a low sperm count with oligoasthenospermia, reduced motility and rapid progression with an abnormal morphology and decreased viability, and a low number of erections. After 1 month, serum PRL levels were signi®cantly reduced in both groups of patients (20.6 6 6.6 mg/l during CAB and 256.3 6 115