Diagnostic efficacy of stereotactic biopsies in intracranial tuberculomas

Abstract

BACKGROUND Stereotactic biopsies for diagnosing intracranial tuberculomas are often reported to be inconclusive, being confirmatory in only 28% of cases. We analyzed the role and diagnostic efficacy of stereotactic biopsies in the management of intracranial tuberculomas. METHODS Twenty patients diagnosed with intracranial tuberculomas based on neuroimaging procedures underwent computerized tomography (CT) guided stereotactic biopsies for histological confirmation. In 10 patients (Group A), biopsies were obtained from the center of the lesion; in the other 10 (Group B), biopsies were obtained from both the enhancing rim and the isodense center and examined separately. The tissues were processed for paraffin sections and hematoxylin eosin staining. In addition, in the first five patients a squash smear from a small portion of the biopsy was prepared, and the cytological features of the cells were examined. All the patients received antitubercular medication and CT scans were repeated 4 months posttreatment. RESULTS Histopathological features of the paraffin sections in 17 patients (Group A: 8, Group B: 9) were diagnostic of tuberculoma, whereas the other three revealed only chronic nonspecific inflammation. Based on the cytological features in squash smears, diagnosis could be made in one of five. In two, although the smear was not diagnostic, the histological section from the same specimen confirmed the tuberculous pathology. There was no procedural morbidity or mortality. One patient had a small asymptomatic hematoma at the biopsy site. Three patients died during the follow-up period, due to secondary complications of tuberculosis. Repeat CT scans during follow-up after antituberculous treatment confirmed the reduction in the size of the lesion in 15/17 patients. CONCLUSION The high positive yield of stereotactic biopsies in diagnosing tuberculomas argues for their inclusion in the management protocol for tuberculous mass lesions.