Background: Craniopharyngiomas are epithelial tumors of the suprasellar region, unanimously defined as benign. Despite the benign histological aspect and apparent gross total resection achieved in a proportion of cases, recurrence rate remains about 30% at 10 years. The role of 7 pathological factors as predictors of recurrence and clinical outcome in craniopharyngioma patients is controversial, as well as the prognostic role of the evaluation of proliferation potential.
Material and methods: In the present study, the proliferation potential of 37 craniopharyngiomas was investigated by analyzing the pattern of Ki-67-MIBI immunoreactivity; the data have been analyzed in relation to age of the patient, histologic type (adamantinomatous/squamous papillary), microscopic and cytochemical features.
Results: Craniopharyngiomas operated in adults have a higher MIB-1-LI than those of children; the epithelial cells abutting the stromal cysts are engaged in the cell cycle, while this is not the case for the cells abutting the nervous tissue; MIB-1-LIs of adamantinomatous craniopharyngiomas are not different from those of squamous papillary craniopharyngiomas, the localization of MIB-1-positive nuclei is different in the 2 craniopharyngioma types, non-epithelial cells proliferate in the stromal component of craniopharyngiomas.
Conclusions: By analyzing these data while considering all available information on the efficacy of surgery and radiotherapy, the proliferation potential of craniopharyngiomas, when evaluated by MIB-1, has no role in the outcome. The very low MIB-1-LI of the intracerebral tumor growth indicates that uncompletely resected tumor remnants do not represent an active starting point of recurrence.