Influence of tumor location on the presentation and evolution of craniopharyngiomas.

OBJECT: This study was performed to optimize the management of craniopharyngiomas, particularly by identifying factors predicting weight changes to prevent obesity.
METHODS: A series of 35 patients who had undergone surgery at a mean age of 7.4 +/- 3.7 years (standard deviation [SD]) and had been followed up until 14.9 +/- 5 years of age by the same endocrinologist were assigned to one of three groups according to their hypothalamic involvement: Group 1 (10 patients) had no involvement, Group 2 (eight patients) had compression without involvement, and Group 3 (17 patients) had severe involvement. Abnormal height and/or weight evolution indicated the craniopharyngioma in only 17% of the patients, although these elements were present at diagnosis in 85%. Before surgery, 85% of the patients lacked growth hormone, 24% lacked thyroid-stimulating hormone, 15% lacked adrenocorticotropin hormone, and 12% lacked antidiuretic hormone. All had complete hypothalamic-pituitary deficiencies after surgery. The body mass index (BMI) before surgery (mean SD 1.1 +/- 1.6) was positively correlated with BMI 1 year after surgery (mean SD 3.1 +/- 2), which correlated with the BMI at the last evaluation (mean SD 3.1 +/- 1.9; p < 0.0001 for both). Before surgery, patients in Group 3 had a greater BMI than did Group 1 (p < 0.02). The BMI of Group 1 patients did not change, but those of Groups 2 and 3 patients increased during the 1st year after surgery (p < 0.02 and p = 0.0003, respectively), with no further change. The changes occurred mainly during the first 3 months after surgery in Group 1, during the first 6 months in Group 2, and throughout the year in Group 3.
CONCLUSIONS: The degree of hypothalamic involvement by the craniopharyngioma determines the presentation and predicts weight changes after surgery.