Frequency and Significance of Lymphoplasmocyte Infiltration in Human Gliomas.

Abstract
The problem of lymphocyte infiltration is studied in 190 operated gliomas and in 35 glioma recurrences. The tumors were classified in 4 groups: no infiltrations (0), infiltrations in a single focus (I), in several foci (II) and extra-adventitial infiltrations (III). 51.59 % of all the gliomas examined were positive for infiltrations, most of them belonging to groups I and II. Plasmacells were found in many group II and group III cases. Lymphoplasmocyte infiltration was considerably increased in group II and group III cases. Cases with such an increase were reoperated within 5 months of the first operation. The findings are discussed in relation to the immunology of tumors and of the nervous system. The increased lymphocyte infiltration in glioma recurrences is attributed to the breakdown of the blood-brain barrier that occurred in the first operation. Lymphocyte infiltration is related to a host defence mechanism against tumors.