Long-term treatment with the dopamine agonist CV 205-502 of patients with a clinically non-functioning, gonadotroph, or alpha-subunit secreting pituitary adenoma

Abstract

Objective: We aimed to assess the effects of prolonged treatment with the dopamine agonist CV 205-502 on tumour volume, visual field defects, and serum gonadotrophin and alpha-subunit concentrations in patients with gonadotroph, alpha-subunit secreting, or clinically non-functioning pituitary adenomas.

Design: The patients were treated with CV 205-502 in a final daily dose of 300 micrograms for at least 1 year. The patients were seen at 2 or 3-week intervals during the first 3 months of treatment, and thereafter every 1 or 2 months. Computerized tomography and Goldmann perimetry were performed before treatment and during follow-up. Blood samples were drawn before treatment and at each out-patient visit.

Patients: One patient with gonadotroph, two with alpha-subunit secreting, and two with clinically non-functioning pituitary adenomas were studied.

Results: Computerized tomography showed tumour shrinkage in one patient. In two other patients an improvement of visual field defects was observed. In four patients, a significant decrease in serum FSH and/or alpha-subunit concentrations occurred within the first 3 months of treatment. In the remaining patient, a significant decrease of serum FSH and alpha-subunit concentrations was found after more than 3 months of treatment.

Conclusions: In patients with clinically non-functioning, gonadotroph, or alpha-subunit secreting pituitary tumours, long-term treatment with the dopamine agonist CV 205-502 decreases serum FSH and/or alpha-subunit concentrations. This decreased secretory activity from the pituitary tumour may be accompanied by an improvement of visual field defects, or tumour shrinkage on computerized tomography. Therefore, treatment with CV 205-502 may be useful in patients with clinically non-functioning, gonadotroph, or alpha-subunit secreting pituitary tumours, who cannot be operated upon.