Outcomes and management strategies after nondiagnostic stereotactic biopsies of brain lesions

Background/Aims: A significant minority of stereotactic biopsies (SBs) of brain lesions is nondiagnostic, yet there are no optimal strategies for preventing nondiagnostic SB (NDSB) and for managing patients after NDSB. We performed this study in order to identify risk factors for NDSB, to determine how diagnoses are eventually reached in these patients, and to ascertain whether NDSB affects clinical outcomes. Methods: Retrospective chart review of patients at our institution who underwent SB of brain lesions. Results: Twenty-four out of 100 SBs were nondiagnostic. NDSB was less likely in contrast-enhancing brain lesions in immunocompetent patients, with larger lesions and in the setting of diagnostic findings on intraoperative frozen section analysis. Of 16 patients with adequate postoperative follow-up, a diagnosis was eventually reached in 11, via further review of the pathology, retrieval of additional tissue specimens or additional noninvasive testing. Survival times for patients with NDSB and eventual tumor diagnoses were within expected ranges for patients with similar tumors. Three of the 5 patients who never received a final diagnosis enjoyed prolonged survival without progressive symptoms. Conclusions: Surgeons should consider taking additional specimens in the case of nondiagnostic intraoperative frozen section during SB. If a tumor is suspected and final pathology is nondiagnostic, outside review of the slides may be helpful, and sampling further tissue should be considered. For diseases other than tumors, the diagnosis will generally be made without a repeat biopsy. The delays in diagnosis resulting from NDSB do not appear to affect survival, at least in patients eventually found to have brain tumors.