Patterns of neuroaxis dissemination of gliomas: suggestion of a classification based on magnetic resonance imaging findings.
BACKGROUND
Local invasion is the hallmark of malignant glioma dissemination. Leptomeningeal dissemination, a serious complication of malignant gliomas, has been increasingly observed. To correlate the physiopathologic mechanisms and the magnetic resonance imaging patterns of neuroaxis dissemination, a classification of malignant glioma dissemination is proposed (Instituto de Neurologia de Curitiba Classification).


METHODS
This classification includes the following patterns of dissemination: leptomeningeal (type I), nodular (type Ia), diffuse (type Ib); subependymal (type II); satellite (type IIIa, IIIb); and mixed (type IV), combination of 2 or more previous types. Of 138 patients with histologically confirmed gliomas treated between 2000 and 2004, 10 presented neuroaxis dissemination and were evaluated.


RESULTS
The distribution of dissemination patterns was as follows: subependymal, 4 of 10; diffuse leptomeningeal, 1 of 10; nodular leptomeningeal, 1 of 10; and satellite, 4 of 10. Mean interval between primary tumor and dissemination was 4 months. The most frequent glioma dissemination risk factor was entering the ventricular system during surgery.


CONCLUSIONS
Improvements in our diagnostic imaging capabilities have contributed to a better understanding of the patterns of malignant glioma dissemination. Using this information, we present a useful classification scheme, applicable to patients with neuroaxis dissemination, which will help standardize future discussions aimed at understanding these patterns of tumor spread.
Bordignon
Kelly Cristina
KC
Neurosurgery Department, Instituto de Neurologia de Curitiba, PR, Brazil. inc@inc-neuro.com.br
Neto
Mauricio Coelho
MC
Ramina
Ricardo
R
de Meneses
Murilo Sousa
MS
Zazula
Ana Denise
AD
de Almeida
Luiz Gustavo Morato Pinto
LG
D000293:Adolescent; D000328:Adult; D000368:Aged; D001932:Brain Neoplasms / Q000145:classification* / Q000473:pathology* / Q000601:surgery; D005260:Female; D005910:Glioma / Q000145:classification* / Q000556:secondary* / Q000601:surgery; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008577:Meningeal Neoplasms / Q000556:secondary; D008875:Middle Aged; D012307:Risk Factors; D016019:Survival Analysis