Hormonal and radiological effects of megavoltage radiotherapy in patients with growth hormone-secreting pituitary adenoma.
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)
Ciccarelli
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E
Dipartimento di Fisiopatologia, Università di Torino, Italy.
Valetto
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MR
Vasario
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E
Avataneo
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T
Grottoli
S
S
Camanni
F
F
D000172:Acromegaly / Q000209:etiology; D000236:Adenoma / Q000378:metabolism* / Q000473:pathology / Q000532:radiotherapy*; D000304:Adrenal Cortex Function Tests; D000328:Adult; D000368:Aged; D005260:Female; D006066:Gonads / Q000502:physiology; D013006:Growth Hormone / Q000097:blood; D006728:Hormones / Q000097:blood*; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000378:metabolism; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D010911:Pituitary Neoplasms / Q000378:metabolism* / Q000473:pathology / Q000532:radiotherapy*; D011882:Radiotherapy, High-Energy / Q000009:adverse effects; D013960:Thyroid Function Tests; D014057:Tomography, X-Ray Computed
D006728:Hormones; D007334:Insulin-Like Growth Factor I; D013006:Growth Hormone