Hormonal and radiological effects of megavoltage radiotherapy in patients with growth hormone-secreting pituitary adenoma.

Abstract

Nineteen acromegalic patients (12 females and 7 males, aged 24-71 yr) were studied for 1-6 yr after radiotherapy (RT), administered by X-rays (18 MeV) by linear accelerator, with parallel opposite beams (doses 45-50.4 Gy, 1.8 Gy daily). Basal GH levels gradually decreased from 6.3-76.2 micrograms/L (mean +/- SE, 27.8 +/- 4.9) to 0.3-43.4 micrograms/L (11.7 +/- 3.6 micrograms/L; p < 0.005) at the last assessment. The earliest significant decrease was observed after one yr (14.9 +/- 3.8 micrograms/L; p < 0.005). Significant changes were observed also in IGF-I values (basal values 1.93-6.85 mU/ml, 3.22 +/- 0.30; last assessment 0.55-4.57 mU/mL, 1.58 +/- 0.31; p < 0.01). The earliest significant decrease of IGF-I values was observed after 2 yr (1.61 +/- 0.16 mU/ml; p < 0.005). GH levels < 5 micrograms/L together with normal IGF-I values were observed in 9 patients, 2-4 yr after RT. No changes were observed in PRL values, either in patients with pretreatment normal or elevated PRL levels. The CT and/or MRI picture of macroadenoma disappeared after 6-12 months in 3/12 patients. Moreover, a reduction (20-55%) in the diameter of the adenoma was shown after 6-36 months in other 4 patients. After RT 5/16 (31%) patients required cortisol and 4/19 (21%) thyroid replacement therapy. In 2/3 men a gonadal impairment was shown, that did not occur in the three female patients with normal gonadal function before RT.(ABSTRACT TRUNCATED AT 250 WORDS)

• Authors: E Ciccarelli, M R Valetto, E Vasario, T Avataneo, S Grottoli, F Camanni
• Journal: Journal of endocrinological investigation (J Endocrinol Invest) Vol. 16 Issue 8 Pg. 565-72 (Sep 1993) ISSN: 0391-4097 [Print] Italy
• PMID: 8258643 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Hormones
• Insulin-Like Growth Factor I
• Growth Hormone

Topics

• Acromegaly (etiology)
• Adenoma (metabolism, pathology, radiotherapy)
• Adrenal Cortex Function Tests
• Adult
• Aged
• Female
• Gonads (physiology)
• Growth Hormone (blood)
• Hormones (blood)
• Humans
• Insulin-Like Growth Factor I (metabolism)
• Magnetic Resonance Imaging
• Male
• Middle Aged
• Pituitary Neoplasms (metabolism, pathology, radiotherapy)
• Radiotherapy, High-Energy (adverse effects)
• Thyroid Function Tests
• Tomography, X-Ray Computed