5-ALA-assisted stereotactic brain tumor biopsy improve diagnostic yield

Abnormal tissue in stereotactic brain biopsies (SBB) is traditionally identified intraoperatively via pathological frozen section (FS), a time-consuming and error-prone process. The objective of this study was to assess the efficacy of 5-aminolevulinic acid (5-ALA) administration on SBB operation time, diagnostic yield, and the associated complication rate.

We retrospectively evaluated all consecutive patients undergoing SBB with preoperative 5-ALA administration and intraoperative assessment of fluorescence (5-ALA group) between 2010 and 2017 in a single center. They were compared to all consecutive patients who underwent traditional brain biopsy with FS (control group). Demographics, clinical data, diagnostic yield of biopsies, and complication rates were documented.

In all, 376 patients underwent SBB for suspected oncological pathology during the study period. All 34 of the 5-ALA-assisted SBB were diagnostic compared to 96.8% of the control group. The mean operative time was the same for both groups, but it was significantly shorter for the 5-ALA patients with florescent samples compared to patients with negative fluorescence (61 ± 25 min vs. 136 ± 54 min, P = 0.003) and compared to the control group (74 ± 34 min vs. 61 ± 25 min, P = 0.03). Symptomatic bleed was absent in the 5-ALA group and present in 5.4% of the controls. No adverse events were associated with preoperative 5-ALA administration.

Preoperative administration of 5-ALA may improve the diagnostic yield of SBB and shortens operation time in cases of fluorescent pathological tissue. In addition, it may reduce the risk for associated postoperative symptomatic bleed. 5-ALA-assisted SBB is a viable alternative to traditional biopsies with FS.