Preoperative Growth Hormone Research Articles

Normal growth hormone secretion is rare after microsurgical normalization of growth hormone levels in acromegaly.

The effect of microsurgery on growth hormone (GH) secretion was studied in 34 patients with acromegaly. All patients showed enlarged sella volumes according to encephalography and macroadenomas at surgery. Preoperative GH levels were elevated in all 34 patients and 14 had concomitant hyperprolactinemia. There was a correlation between basal GH levels and sella size. Visual field defects, suprasellar extension, long duration of the disease, hyperprolactinemia and aneuploidy were noted in patients with low as well as high levels of GH preoperatively. The average reduction of GH levels in the total series was 71 +/- 21% (mean +/- SD). A notably similar reduction of GH levels was seen regardless of preoperative GH levels, concomitant hyperprolactinemia, visual field defects, size of the adenoma, invasive growth or increasing experience of the surgeon. Therefore, normal GH levels after surgery were reached mainly in patients with moderate GH increments preoperatively. GH levels were normalized by surgery in 15 patients but only four of these showed normal GH response to TRH and iota-dopa tests. Thus, only four patients (12%) fulfilled these criteria for cure of GH homeostasis.

Acromegaly: analysis of 132 cases treated surgically.

The surgical treatment of 132 acromegalics is analyzed. There was an equal sex distribution among patients between the ages of 30 and 59. In the younger patients there was a preponderance of males, and the opposite situation occurred in patients older than 59 years. The overall cure rates were 58% (growth hormone (GH) less than 5 ng/ml) and 78% (GH less than 10 ng/ml). Endocrinological evidence of cure was observed most commonly in patients who exhibited preoperative GH values below 70 ng/ml.

Cryohypophysectomy for acromegaly: Factors associated with altered endocrine function and carbohydrate metabolism

After Cryohypophysectomy, fasting levels of growth hormone (GH) fell to less than 10 ng/ml in 38 (76 per cent) of 50 patients with acromegaly. Effects, including lowered serum insulin levels and improved glucose tolerance, were rapid and long-lasting. Optimal endocrine-metabolic results, defined as lowering of the GH level to 10 ng/ml or less and normal glucose tolerance (attained in 60 per cent of patients), were most often achieved when preoperative glucose tolerance was normal or mildly abnormal. Factors that favored optimal lowering of GH were preoperative GH level below 50 ng/ml and moderately, rather than greatly, enlarged sellae turcica. Factors that favored normal carbohydrate balance after treatment were postoperative fasting GH level of 10 ng/ml or less and preoperative symptom duration of 10 years or less. A family history of diabetes was not an important over-all factor in glucose intolerance. Although postoperative reduction in 24-hour urinary excretion of 17-hydroxycorticosteroids was associated with adequate GH reduction, adrenal reserve and thyroid function remained normal in most patients. In contrast to the prognostic significance of high GH levels, adrenal and thyroid function could not be related to eventual GH response or to carbohydrate metabolism.

Influence of pituitary stalk section on growth hormone, insulin and TSH secretion in women with metastatc breast cancer.

ABSTRACT The effect of pituitary stalk section on growth hormone secretion, insulin secretion and carbohydrate tolerance was studied in 13 women with advanced metastatic breast cancer. Plasma immunoreactive growth hormone concentrations were measured during standard insulin tolerance tests in 8 women preoperatively and 12 women postoperatively. Glucose disappearance rates (Kg), plasma growth hormone and insulin concentrations were measured after the rapid intravenous administration of glucose in 5 women preoperatively and 9 women postoperatively. In addition, the acute effect of stalk section on thyroidal discharge rate was studied in one patient. Measurable growth hormone levels in the fasting state were found on one or more occasions in 4 out of 8 patients studied during the early postoperative period. None of the 5 patients studied 8 months or longer after surgery had detectable levels of growth hormone under basal conditions. Peak preoperative growth hormone responses to insulin were between 22 and 11...