Diencepephalic Syndrome Before Diagnosis of Childhood Craniopharyngioma – Results of Multinational Studies on 485 long-term Survivors after Childhood Craniopharyngioma

Background: Hypothalamic involvement (HI) resulting in severe obesity is known to have major impact on quality of life in craniopharyngioma (CP) patients. HI is also associated with disturbances of satiety regulation leading to a failure to thrive and weight loss known as diencephalic syndrome (DS). The rate of DS and the outcome of CP patients with DS is unknown.

Methods: 485 CP patients have been recruited in HIT-ENDO and KRANIOPHARYNGEOM 2000/2007. 21 CP patients (4.3%) presented with a BMI<-2SD at diagnosis. In 4 of 21 cases low BMI could be explained by prematurity or congenital heart failure. 11 patients presented with DS due to proven hypothalamic involvement (HI). 3 patients presented without HI, in 3 patients HI was not evaluable. We compared weight development since birth at standardized time points (based on a German health survey) in CP presenting DS, normal weight or obesity (BMI>3SD) at the time of diagnosis.

Results: Weight development during early childhood could be analyzed in 9 of 11 DS patients. Decreases in BMI (>-1SD) were detectable in 4 patients within the first year of life, in 2 patients in the second year of life, in 2 patients in the 5th year, one patient was already dystrophic at birth. Accordingly, 7 of 11 patients showed BMI reduction within the first two years of life. During follow-up, DS patients showed a significant postoperative weight gain comparable to patients who presented with normal weight at time of diagnosis resulting in obesity (median BMI +3.98SD) after 8-12 years.

Conclusion: DS is a rare clinical manifestation of CP. In the majority BMI SDS reduction becomes manifest in early childhood, in some cases changes in BMI SDS develop later, but years before other symptoms are obvious. Low BMI at time of diagnosis does not prevent weight gain in CP with DS.