Background: Most primary intracranial tumors occur as solitary lesions; multiple locations of one tumor, the occurrence of two different tumors or even collision tumors have been described only in a few patients. From a statistical point of view, in less than 100 glioblastoma cases will a meningioma be simultaneously present in the brain. We report three cases with this coincidence and display the results of CGH and chromosome analysis in two patients, in whom the tumors arose in very close spatial correlation to each other.
Patients: We describe three case histories with simultaneous occurrence of meningioma and glioblastoma as shown by MRI on admission. After neurosurgical removal of mass lesions, specimens from two patients were cultivated in cell culture and the cells were examined for chromosomal aberrations by conventional karyotyping as well as comparative genomic hybridization (CGH).
Results: Examinations disclosed characteristic genetic aberrations for one meningioma and two glioblastomas. In one patient it was possible to compare the data for the meningioma and the glioblastoma; in this case we did not find a common genetic aberration in tumor cells with a different histology.
Conclusion: Genetic testing of tumor cells should be performed routinely when different histological types of brain tumors are present in a close spatial relationship. We favor the hypothesis of statistical coincidence for the simultaneous occurrence of the two tumors rather than a common pathway giving rise to two tumor entities.