Stereotactic biopsy for brain tumors: is it always necessary?

Stereotactic biopsy is currently being used in oncological neurosurgery despite its limitations. The purpose of this study is to compare its diagnostic reliability with that of the diagnosis based on clinical data and neuroimaging techniques.

We studied 200 patients (134 men and 66 women) who underwent 212 stereotactic biopsy procedures to assess brain tumors. All were subjected to CT scan and 71 patients also underwent MRI. A presumptive diagnosis of brain tumor was established in each case and the findings compared with the results of stereotactic biopsy and the clinical course.

A clear presumptive diagnosis was established before stereotactic biopsy in 90% of the patients, and in 95% of this group, the diagnosis was confirmed by the biopsy and/or the clinical course. The stereotactic biopsy modified the presumptive diagnosis in eight patients (4%), without changing the clinical diagnosis of malignant lesion. In our present series, 10% of the procedures were of no help in determining a diagnosis and in 7% of patients, the stereotactic biopsy led to diagnostic errors that influenced the therapeutic management and resulted in an erroneous prognosis.

These data confirm the need for clinical correlation with the findings obtained at stereotactic biopsy and suggest that stereotactic biopsy may not always be useful or necessary in the management of brain tumor patients. According to our present critical analysis, when a clear presumptive diagnosis of brain tumor can be made, it may be sufficient to base the management of the patient only on clinical and neuroimaging findings.