Can recurrence of meningiomas be predicted?

After resection of meningiomas the clinical evolution remains problematic, as no clear-cut predictive criteria are available. In vitro evaluation of meningiomas might help to predict their evolution in vivo after resection. For this goal a confrontation model was tested. A group of 105 patients operated for meningiomas between 1986 and 1997 were reviewed at 3, 5, 10 and 15 years for tumour evolution by tomodensitometry or magnetic resonance. At operation a fragment of these resected tumours was explanted for cell culture and was confronted with embryonic chick heart as a host tissue. The confrontation between tumour- derived cells and host tissue resulted in three different patterns: respectively a regressive, a non-invasive and an invasive pattern. Resection type, proliferation markers (Ki67 and PCNA) and in vitro confrontation patterns were significant (p<0.05) factors in predicting the postsurgical evolution of meningiomas. No correlation was found between proliferation markers and the behaviour in vitro, but invasion in vitro was strictly correlated with recurrence and malignancy of meningiomas.