Hormonal factors influencing weight and growth pattern in craniopharyngioma

Patients operated on for craniopharyngioma frequently suffer from hyperphag ia and are obese, but their statural growth is normal despite growth hormon e (GH) deficiency. We have evaluated the hormonal factors influencing chang es in weight and growth in 17 children before and 1, 3-6, 12, and/or 24 mon ths after surgical resection of a craniopharyngioma performed at 7.7 +/- (S E) 1 years of age. Of these, 15 patients had a GH deficiency before surgery , and all had complete pituitary deficiency after it. The plasma fasting in sulin concentrations before surgery were positively correlated with body ma ss index (BMI, kg/m(2); p < 0.05), plasma insulin-like growth factors (IGFI , p = 0.03, and IGFII, p = 0.04), and leptin (p = 0.03). They increased sig nificantly 1 month after surgery and continued to increase thereafter, wher eas leptin increased significantly only 3-6 months after surgery, paralleli ng changes in BMI. The plasma fasting insulin concentrations before surgery were also positively correlated with the weight changes (12.3 +/- 2.3 kg, p < 0.01) during the 12 months after surgery, but not with changes in BMI S DS (3.1 +/- 0.5, p = 0.07). Both expressions of weight change were correlat ed with the concomitant growth rates (4.8 +/- 0.7 cm, p < 0.01). IGFI was a bove the 10th percentile for children with idiopathic short stature in 10 o f 15 patients with craniopharyngioma-induced GH deficiency and IGF-binding protein 3 in 14 of 15 patients. Craniopharyngioma itself modified the contr ol of insulin secretion, and surgery increased the insulin secretion which continued in the same way in a given patient after surgery. The increased i nsulin secretion in turn increases weight and keeps IGFI nearly normal. Thi s may explain the normal growth rate despite the complete lack of GH. Copyr ight (C) 2000 S. Karger AG, Basel.