Postoperative pituitary hormonal disturbances and hormone replacement therapy time and dosage in children with craniopharyngiomas.

BACKGROUND: The proliferative activity and penetration into the hypothalamic structures in children craniopharyngiomas (CP) often make radical resection difficult. Therefore, complete resection of CP often results in permanent multiple pituitary hormone deficiency (MPHD). This study aimed to elucidate the postoperative pituitary hormonal disturbances, and hormone replacement therapy (HRT) time and dosage in children with CP.

METHODS: Twenty patients with growth retardation and CP after resection, comprising 14 boys and 6 girls, with a mean age of (10.63 +/- 3.18) years (Group A) and 10 male patients of group A aged > 10 years (Group B) were entolled. Thirty age-, sex- and Tanner stage-matched normal children (control Group A), and 44 male older children > 10 years (control Group B) served as controls. The serum concentrations of insulin-like growth factor-1 (IGF-1), growth hormone (GH), free thyroxine (FT4), thyroid-stimulating hormone (TSH), adrenocorticortropic hormone (ACTH), cortisol (COR), follicle stimulating hormone (FSH), luteinizing hormone (LH), prolactin (PRL), testosterone (T) and estradiol (E2) were measured in the CP patients after resection and in controls. The appropriate time and dosage of HRT were investigated. Linear correlation analysis was made between levothyroxine (L-T4) dosage and primary FT4 in CP patients after resection.

RESULTS: All cases had MPHD. The serum peak GH, IGF-1, FT4 and COR levels of Group A were significantly lower than that of the control Group A. The serum IGF-1 concentration increased to the normal level after 3 months of rhGH therapy; the serum FSH, LH, and T levels were significantly decreased (P < 0.001); however, E2 and PRL were significantly increased (P < 0.001) in Group B compared with the control Group B; 18 cases were found to have central diabetes insipidus (DI) by water deprivation test and MRI. There was a significant negative linear regression (r = -0.8, P < 0.001) between L-T4 and primary FT4 in Group A patients with CP after resection, giving a regression equation of L-T4 dosage (microg.kg(-1).d(-1)) = 3.5-0.2 x FT4 (microg.kg(-1).d(-1)). The time and corresponding dosage of HRT for CP after resection were: rhGH started 1 year after resection and no recurrence of CP on MRI, when IGF-1 reached the normal range, the rhGH dosage was (0.13 +/- 0.04) U.kg(-1).d(-1); hydrocortisone (H-C) was started as soon as possible, and was kept in the lower normal range, at a dosage of (12.6 +/- 4.8) mg/m2; levothyroxine started after H-C or at the same time to maintain FT4 in the higher normal range, at a dosage of (1.65 +/- 0.70) microg.kg(-1).d(-1); Minirin (DDAVP) was started as soon as possible, elicited no symptoms, and maintained normal electrolyte levels; the dosage was (0.16 +/- 0.04) mg/m2.

CONCLUSION: Patients with CP after resection often displayed MPHD, and needed total HRT at appropriate time and dosage to improve the quality of life and normal growth.