Multicentric glioma: problems & interpretations. [corrected]

The authors report four patients suffering from multicentric intraparenchymatous malignant glioma lesions located in different regions of the brain. The incidence of multiple, separated, independent, non-connected neuroepithelial tumors in the same patient is rare, although a discrepancy exists in the literature with regard to its real incidence. There is also controversy with respect to the histological composition of these tumors. In some cases, identical histopathological composition has been found, while in others different cellular patterns are present. Several hypotheses have been put forward to try to explain the occurrence of multicentric glioma tumor in the same patient. They consist of disseminations (through white matter tracts, cerebrospinal fluid pathways, or metastatic satellites around the vicinity of the tumor) or simultaneous development of different tumors, independent from each other.