Relationship of angiogenic potential with clinical features in cranial meningiomas: a corneal angiogenesis study.
BACKGROUND
Intracranial meningiomas constitute approximately one fourth of all primary intracranial tumors. The invention of cranial angiographic techniques has led to the recognition of the angiogenic potential of meningiomas, which has been the subject of extensive research.


OBJECTIVE
To test the relationship between the angiogenetic potential of intracranial meningiomas and clinical/prognostic features such as World Health Organization (WHO) grade, peritumoral edema, tumor border shape, and recurrence using rat corneal angiogenesis assay.


METHODS
Fifteen WHO grade I (typical), 10 WHO grade II (atypical), and 5 WHO grade III (malignant) meningioma samples were implanted in the micropockets formed on rat corneas, and the number of developed vessels were counted on days 5, 10, 15, and 20. Normal brain and glioblastoma multiforme tissues served as negative and positive controls, respectively. Patients were evaluated by magnetic resonance imaging preoperatively and every 6 months thereafter.


RESULTS
The angiogenic potential of WHO grade II tumors was significantly lower than that of grade III tumors and higher than that of grade I tumors throughout the experiment. Tumors with a smooth border shape and nonrecurrent tumors exhibited significantly lower angiogenic activity compared with the tumors with irregular border shape and recurrent tumors, respectively. No association was found between angiogenic activity and peritumoral edema. However, multivariate analysis identified WHO grade, recurrence, and peritumoral edema as significant predictors of a high angiogenic potential.


CONCLUSIONS
Our findings, based on a dynamic in vivo model to examine angiogenesis, demonstrate that the angiogenic potential of meningiomas is correlated with WHO grade, recurrence, and possibly with tumor border shape and peritumoral edema. Angiogenesis seems to be an important factor in the natural course of meningiomas, suggesting that inhibition of angiogenesis may be an option, particularly in the treatment of meningiomas with an aggressive course.
Institute of Neurological Sciences, Laboratory of Molecular Neurosurgery, Department of Neurosurgery, Marmara University, Istanbul, Turkey.
Zafer Orkun
ZO
Toktas
Emel
E
Akgun
Abdulkadir
A
Ozkan
Suheyla Uyar
SU
Bozkurt
Nural
N
Bekiroglu
Askin
A
Seker
Deniz
D
Konya
Turker
T
Kilic
D000328:Adult; D000818:Animals; D001929:Brain Edema / Q000209:etiology; D016510:Corneal Neovascularization / Q000209:etiology* / Q000473:pathology*; D004195:Disease Models, Animal; D005500:Follow-Up Studies; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008577:Meningeal Neoplasms / Q000150:complications* / Q000473:pathology; D008579:Meningioma / Q000150:complications* / Q000473:pathology; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local; D051381:Rats; D017207:Rats, Sprague-Dawley; D012189:Retrospective Studies; D013997:Time Factors; D016378:Tissue Transplantation / Q000379:methods; D014944:World Health Organization