2006 Volume 15 Issue 1 Pages 39-46
In 184 cases harboring meningiomas that we performed the surgical resection between 1993 and 1998,36cases were recurrent. In these recurrent cases, we investigated 15 cases that were removed totally (Simpson I or II )with first operation. We classified those 15 cases into three groups on the basis of WHO brain tumor's histological classification of 2000.
Group A was included atypical or anaplastic meningiomas from onset to recurrence. Group B was included the cases changing from benign type to atypical or anaplastic meningiomas. Group C was included the cases showing histologically benign type in the recurrence. About those three groups, we studied MIB-1 LI by immunohistology, DNA index with FCM.
In the group A (histologically, malignant to malignant), MIB-1 LI was initially high value, but recurrently high value. DNA index had the same tendency.
In the group B( histologically, benign to malignant), MIB-1 LI showed initially low value, but recurrentlly into high value. DNA-index has the same tendency except case 4. Only DNA index of case 4 was initiallyl.08slight high and malignant.
In the group C (histologically, benign to benign), MIB-1 LI was initially low, but recurrently medium or high. DNA-index has two tendencies. One is initially low, but recurrently low, and the other is initially low, but recurrently slight high.
DNA-histogram in the group A and B revealed aneuploidy pattern. In the group C, it revealed all diploid pattern.
In the result of that, MIB-1 LI and DNA index were correlated each other.
But in the group B and C, it was hard to predict the malignant change except case 4. For the purpose of the effective prediction, we will need more studies including other predictive factors and accumulation of the cases.
In recurrent meningiomas, there were some cases having high proliferative rate in spite of histologically benign. We concluded not only histological malignancy but also proliferative rate were very important, when we predict it's recurrence.
