PURPOSE: Molecular data has become an essential part of the updated World Health Organization (WHO) grading of central nervous system tumors. However, stereotactic needle biopsies provide only small volume specimens and limit the extent of histologic and molecular testing that can be performed. We assessed the use of a tubular retractor-based minimally invasive biopsy technique to provide improved tissue yield and diagnostic data compared to needle biopsy. METHODS: Eighteen patients underwent an open transtubular biopsy compared to 146 stereotactic biopsies during the years of 2010-2018. RESULTS: Tubular biopsies resulted in a higher volume of tissue provided to the pathologist than needle biopsies (1.26 cm3 vs. 0.3 cm3; p < 0.0001). There was a higher rate of non-diagnostic sample with stereotactic compared to transtubular biopsy (13% vs. 0%; p = 0.13). Six patients who underwent stereotactic biopsy required reoperation for diagnosis, while no transtubular biopsy patient required reoperation in order to obtain a diagnostic specimen. Postoperative hematoma was the most common post-operative complication in both groups. CONCLUSIONS: Stereotactic transtubular biopsies are a viable alternative to stereotactic needle biopsies with excellent rates of diagnostic success and acceptable morbidity relative to the needle biopsy technique. As molecular data begins to increasingly drive treatment decisions, additional biopsy techniques that afford large tissue volumes may be necessary to adapt to the new needs of pathologists and treating oncologists.
