Morphological and ultrastructural findings of prognostic impact in craniopharyngiomas

ABSTRACT Craniopharyngioma is a slow-growing epithelial tumor with an unpredictable tendency to recur. To verify the reliability in predicting the clinical outcome, some morphological and immunohistochemical findings were analyzed in 37 primitive tumors and in 6 recurrences (one recurred twice). All the tumors were surgically excised and all recurrences exhibited an adamantinomatous pattem; mitotic rate was low (<5 >< 10 HPF) in both recurrent and in nonrecurrent tumors. Primary tumors showed a mean posi- tivity of 1.7% (range 0.3-2%) to PCNA vs. 4.1% (range 0.3-8%) in recur- rences. The MIB—1 labelling Index was: 22.12% in primary tumors, 27.5% in recurrences, 31.3% in adult nonrecurrent tumors, and 4.1% in the pedi- atric tumor. CD34 labeling vessels/field was 9.3 in primary tumors and 9.91 in the recurrences; VEGF expression was higher in recurrences than in pri- mary tumors (40 vs. 25%). Ultrastructural analysis showed fenestrated endo- thelium with hydropic changes in VEGF-positive vessels. lack of clear correlations between morphological or immuno-staining patterns and beha- vior suggests that these features have no prognostic value in adult as well as in pediatric craniopharyngiomas. In this study, the only results that may be related to the aggressiveness of tumor is the major vascularization in the recurrent tumors in which the vessels show also ultrastrudural changes.