Maria Luisa Landi

Pregnancy outcome after cabergoline treatment in early weeks of gestation

We collected information on 61 pregnancies in 50 women treated with cabergoline. These pregnancies resulted in 12 (19.7%) early terminations (five induced abortions, six spontaneous abortions, one hydatidiform mole) and 49 (80.3%) live births. In one case, malformations were suspected by a gynecologist based on ultrasound at 12 gestational weeks and the pregnancy was terminated; additional information was not available. There was one case of trisomy 18. The frequency of spontaneous and induced abortions and major congenital malformations was comparable with rates in the general population. The data did not indicate any potential adverse effect of the drug on pregnancy. The data from this study in combination with previous reports can exclude a congenital malformation risk greater than 10% associated with pregnancy exposure to cabergoline.

The effect of quinagolide and cabergoline, two selective dopamine receptor type 2 agonists, in the treatment of prolactinomas

To compare effectiveness and tolerability of quinagolide (CV 205–502) and cabergoline (CAB) treatments in 39 patients with prolactinoma.

New Medical Approaches in Pituitary Adenomas

Recently, the medical approach to patients with secreting and clinically non-functioning pituitary adenomas has received great impulse thanks to the availability of new, selective and long-lasting compounds with dopaminergic activity, such as cabergoline, and of somatostatin analogues provided in slow-release formulations, such as lanreotide and octreotide long acting release (LAR). In particular, the use of cabergoline has induced control of hyperprolactinaemia and tumour shrinkage in the great majority of patients with micro- and macroprolactinomas. Cabergoline treatment restores fertility both in women and men, and partially improves osteoporosis, one of the major complications of hyperprolactinaemia. In acromegaly, disease control (growth hormone [GH] <2.5–1.0 μg/l as a fasting or glucose-suppressed value, respectively, together with age-normalised insulin-like growth factor [IGF]-I) is achievable in more than half of patients receiving treatment with lanreotide or octreotide-LAR. Improvement in cardiomyopathy, sleep apnoea and arthropathy has been reported during GH/IGF-I suppression after pharmacotherapy. A synthetic GH analogue, B2036-PEG, that antagonises endogenous GH binding to its receptor-binding sites and a GH-releasing hormone antagonist that blocks the effect of this releasing factor on the hypothalamus and pituitary are presently under investigation in acromegaly. Preliminary studies have clearly demonstrated the effectiveness of the GH receptor antagonist in suppressing IGF-I levels in acromegalic patients previously unresponsive to somatostatin analogues. Beneficial effects of subcutaneous octreotide and lanreotide have also been reported in adenomas secreting thyroid-stimulating hormone, while the results of treatment with dopamine agonists or somatostatin analogues remain disappointing in patients with clinically non-functioning adenomas. In these patients the possibility of visualising in vivo the expression of D2 receptors using specific radiotracers such as 123I-methoxybenzamide has allowed selection of patients likely to respond to cabergoline. Scant effects of pharmacotherapy have also been reported in patients with adenomas secreting adrenocorticotropic hormone. However, some preliminary data suggest a potential use of cabergoline in combination with ketoconazole, or alone, in selected cases of Cushing’s disease or Nelson’s syndrome.

Cardiovascular aspects in acromegaly: Effects of treatment

Patients with acromegaly have significant morbidity and mortality, associated with cardiovascular disease. Acromegaly is often complicated by other diseases such as diabetes mellitus, hypertension, and coronary artery disease, so the existence of acromegalic cardiomyopathy remains uncertain. Cardiac performance was investigated in patients with uncomplicated acromegaly. A subgroup of hypertensive acromegalics was also studied. In addition, the effects of chronic octreotide therapy or surgery on cardiac structure and function in acromegaly were studied. Twenty-six patients and 15 healthy controls underwent gated blood-pool cardiac scintigraphy and echocardiography at rest and during exercise. Echocardiography was repeated after 6 months of octreotide therapy (n = 11). Cardiac scintigraphy was repeated after 12 and 24 months of octreotide therapy (n = 10) or 12 to 24 months after surgery (n = 8). ECG, blood pressure, and heart rate were monitored during cardiac scintigraphy. Left ventricular mass (LVM) was calculated from the findings of the echocardiography. Serum growth hormone (GH) levels and plasma insulin-like growth factor-1 (IGF-1) levels were monitored. LVM index was significantly higher (P < .003) in acromegalics than controls and in hypertensive acromegalics than normotensives, but all other indices of cardiac function were similar. Chronic octreotide decreased GH and IGF-1 levels and improved the structural abnormalities as measured by echocardiography. Chronic octreotide or surgery did not alter cardiac function parameters. Thus, important changes in cardiac structure and function occur in uncomplicated acromegaly, and improvements can be demonstrated after chronic octreotide therapy. Heart disease in acromegaly appears to be secondary to high circulating GH levels.

Comparison among Different Dopamine-Agonists of New Formulation in the Clinical Management of Macroprolactinomas

BACKGROUND In the last decade, the treatment of macroprolactinomas has been significantly improved by the introduction in the clinical practice of new drugs with dopamine-agonist properties. In particular, the availability of different forms of bromocriptine (BRC) with long duration of action and slow absorption, suitable for injectable (BRC-LAR) or oral (BRC-SRO) administration, has allowed one to obtain a more constant bromocriptinemia than with standard BRC, thus reducing adverse reactions. Moreover, a selective action on dopamine D2 receptors has been achieved using a new non-ergot derivative: the quinagolide (CV 205-502). The aim of this study was to evaluate the effects of BRC-LAR, BRC-SRO and CV 205-502 in 34 patients with macroprolactinoma. PROTOCOL OF THE STUDY: BRC-LAR was given at the monthly dose of 50-100 mg for 6-24 months to 8 patients whose PRL levels were 150-700 micrograms/l. BRC-SRO was given at the daily dose of 5-20 mg for 1-24 months to 10 patients whose PRL levels were 120-900 micrograms/l. CV 205-502 was given at the daily dose of 0.075-0.6 mg for 6-12 months to 16 patients whose PRL levels were 250-2,050 micrograms/l. CT and/or MRI scans were performed before and during treatment to evaluate tumor shrinkage. Data are presented as Mean +/- SD. RESULTS Serum PRL levels normalized in 8/8 with BRC-LAR, 7/10 with BRC-SRO and 12/16 patients with CV 205-502. A significant shrinkage of tumor mass was obtained in 7/8 with BRC-LAR, 9/10 with BRC-SRO and 16/16 patients with CV 205-502, with consequent improvement of visual-field defects. Overall, the drugs were rather well tolerated: no patient stopped BRC-LAR or BRC-SRO and only 2 stopped CV 205-502. In particular, nausea, vomiting, headache, hypotension that disappeared spontaneously were observed in 5/8 with BRC-LAR, 4/10 with BRC-SRO and 4/16 with CV 205-502. CONCLUSIONS The medical approach with long-acting BRC preparations and CV 205-502 which selectively binds D2 receptors allows one to obtain rapid normalization of PRL levels and shrinkage of macroprolactinomas in a large series of patients. These drugs are rather well tolerated also by patients proven to be untolerant to standard BRC.

CV 205–502 in the treatment of tumoral and non-tumoral hyperprolactinemic states

CV 205-502 (octahydrobenzol[g]quinoline), a non-ergot dopamine agonist drug, was administered to 40 patients with hyperprolactinemic syndrome: 16 patients with macroprolactinoma, 14 with microprolactinoma and 10 with non-tumoral hyperprolactinemia. Twenty-four out of 40 patients had previously been treated by surgery and/or bromocriptine, with variable results. All had gonadal dysfunction and 22 patients had galactorrhea. Eight patients with macroprolactinoma had defects of the visual field. Pre-treatment serum PRL levels ranged from 60 to 2050 micrograms/l. The daily dose of CV 205-502 used in this trial ranged from 0.075 to 0.600 mg. After 6-12 months of treatment, serum PRL level decreased in all the patients reaching normoprolactinemia in 31 of them (77.5%) who demonstrated restoration of menses and disappearance of galactorrhea. The remaining nine patients (22.5%) had only a decrease of PRL levels without reaching normoprolactinemia and without any clinical effect. In 12 out of 16 patients with macroprolactinoma not previously surgically treated, a significant tumor shrinkage was shown by means of Computed Tomography and/or Magnetic Resonance Imaging. The disappearance of visual defects was obtained in four out of eight patients. CV 205-502 was tolerated satisfactorily: mild side-effects occurred in four patients in the first week of treatment and spontaneously disappeared, whereas six patients (15%) needed to withdraw the therapy after 6 months because of side-effects. In conclusion CV 205-502 is a potent and well-tolerated drug in the treatment of tumoral and non-tumoral hyperprolactinemic states and is an effective alternative to other dopamine agonists in use today.

Different sensitivity to sodium valproate in healthy, non-tumoral and tumoral hyperprolactinemic subjects

GABAergic drugs affect PRL secretion in both rat and man. Sodium valproate (SV) inhibits GABA transaminase so increasing the endogenous GABAergic tone. The aim of this study was to evaluate the effects of SV at low and high doses on PRL release in healthy subjects and hyperprolactinemic patients. Fifteen patients with prolactinomas, 8 patients with non-tumoral hyperprolactinemia and 10 healthy subjects were studied: in non consecutive days, all subjects received placebo and SV at the dose of 400 and 800 mg po. Serum PRL levels were assessed 30, 15 and 5 min before and every 30 min for 4 hours after administration. SV at the dose of 400 mg induced a significant decrease of serum PRL in healthy subjects (p<0.05), whereas no effect was noted in both tumoral and non-tumoral hyperprolactinemia. The administration of 800 mg SV induced a significant decrease of PRL levels in healthy subjects and in patients with non-tumoral hyperprolactinemia (p<0.05). Conversely, in prolactinomas a paradoxical increase of serum PRL concentration (p<0.05) was observed 120 min after the administration of the drug. These data confirm the inhibitory activity of SV on PRL release in healthy subjects, and suggest the existence of a partial resistance to GABA in non-tumoral hyperprolactinemia. In prolactinomas, the paradoxical PRL increase after high dose of SV suggests the existence of a complete pituitary resistance to GABA. This finding might be explained by the appearance of the stimulatory effect of GABA at hypothalamic level that could have been unmasked by the lack of pituitary GABA effects on adenomatous lactotrophs.

Resistance to cabergoline as compared with bromocriptine in hyperprolactinemia : Prevalence, clinical definition, and therapeutic strategy

To evaluate the prevalence of resistance to cabergoline treatment, we studied 120 consecutive de novo patients (56 macroadenoma, 60 microadenoma, 4 nontumoral hyperprolactinemia) treated with cabergoline (CAB) compared with 87 consecutive de novo patients (28 macroadenoma, 44 microadenoma, 15 nontumoral hyperprolactinemia) treated with bromocriptine (BRC) for 24 months. Resistance was evaluated as inability to normalize serum PRL levels (first end point) and to induce tumor shrinkage (second end point). After 24 months, PRL normalization and tumor shrinkage after CAB and BRC treatments, respectively, were obtained in 82.1% and 46.4% of macroprolactinomas (P < 0.001) and in 90% vs. 56.8% of microprolactinomas (P < 0.001). The median doses of CAB and BRC able to fulfill the two criteria of treatment success were 1 mg/wk and 7.5 mg/d in macroprolactinomas, 1 mg/wk and 5 mg/d in microprolactinomas, and 0.5 mg/wk and 3.75 mg/d in nontumoral hyperprolactinemia. Hyperprolactinemia persisted in 17.8% of macroprolactinomas, 10% of microprolactinomas, and after CAB at doses of 5-7 mg/wk and in 53.6% of macroprolactinomas, 43.2% of microprolactinomas, and 20% of nontumoral hyperprolactinemic patients, after BRC at doses of 15-20 mg/d. In these resistant macro- and microprolactinomas, the maximal tumor diameter was reduced by 43.7 +/- 3.6% and 22.1 +/- 3.7% and by 59.3 +/- 7.1% and 4.3 +/- 2.1% after CAB and BRC, respectively (P < 0.001). In conclusion, long-term CAB treatment induced the successful control of hyperprolactinemia associated with tumor shrinkage in a higher proportion of patients than did BRC treatment. In a small number of patients (i.e. 17.8% of macroprolactinomas and 10% of microprolactinomas), however, CAB treatment did not normalize serum PRL levels despite reducing tumor mass, even at very high doses. Therefore, an absence of tumor shrinkage cannot be considered as end point to indicate resistance to CAB, and increasing the dose of CAB higher than 3 mg/wk does not seem to be helpful in controlling PRL hypersecretion.

Trattamento dell’acromegalia: attualità e prospettive

RiassuntoL’acromegalia è una malattia rara ma severa, il cui trattamento prevede un approccio integrato tra terapia medica, chirurgica e radioterapia. Tale schema terapeutico consente attualmente di curare la malattia nel 75% dei casi. In questo articolo, presenteremo le più recenti acquisizioni e le nuove prospettive nel trattamento terapeutico dell’acromegalia.

Long-Term and Low-Dose Treatment with Cabergoline Induces Macroprolactinoma Shrinkage

Cabergoline (CAB), a long-lasting dopamine-agonist, specific for the D2 receptor, is effective in normalizing serum PRL levels in most patients with microprolactinoma or idiopathic hyperprolactinemia. Because few data are presently available on the effects of CAB treatment in macroprolactinomas, the aim of this open-label study was to investigate whether this drug was effective in producing tumor shrinkage, as well as in normalizing PRL levels. Twenty-three patients with macroprolactinoma entered this study 15 patients had had no treatment, whereas the remaining 8 patients had been previously treated with bromocriptine, which was with-drawn because of intolerance. Three of 23 patients had undergone unsuccessful surgery. Pretreatment serum PRL levels ranged from 100-3860 micrograms/L. CAB was administered at a dose of 0.5-3 mg once or twice a week for 12-24 months. Magnetic resonance imaging (MRI) scans were performed before and 3, 6, 12, and 24 months after the beginning of treatment, to evaluate tumor shrinkage, defined as a decrease of at least 80% of baseline tumor volume. After 3-6 months of treatment with a low dose (0.5-1 mg/week), serum PRL levels normalized in 18 patients. In the remaining 5 patients, whose serum PRL levels were not normalized, the dose was increased to 2-3 mg/week. This schedule caused the normalization of PRL levels in 1 patient, whereas in the remaining 4 patients, PRL levels were reduced to 30-82 micrograms/L. A tumor volume reduction greater than 80% at MRI occurred in 14 of 23 patients (61%) after CAB treatment (from 2609.4 +/- 534.7 to 530.1 +/- 141.3 mm3 at the 12-24th month follow-up, P < 0.001). A volume reduction of 41.8 +/- 3.4% was already evident after 3 months (1436 +/- 285.9 mm3; P < 0.001). The complete disappearance of the tumor mass at MRI occurred after 6 months of treatment with CAB in 1 patient, and in 5 patients after 1 yr of treatment. An improvement of visual field defects was obtained in 9 of the 10 patients presenting visual impairment before CAB treatment. The drug was tolerated well by all patients. Only 1 patient experienced mild nausea, which disappeared spontaneously after the 2nd day of treatment. Long-term, a low dose of the D2 receptor agonist CAB significantly reduced tumor volume and normalized serum PRL levels in a great majority of patients bearing macroprolactinoma. This treatment met with excellent patient compliance. This study suggests that CAB can be used as a first choice drug treatment in macroprolactinomas, as already shown for microprolactinomas and idiopathic hyperprolactinemia.