Abstract Date: 5/2/2015
Darryl Lau, MD
Shawn Hervey-Jumper, MD
Susan Chang, MD
Annette Molinaro, PhD
Michael McDermott, MD
Joanna Phillips, MD, PhD
Mitchel Berger, MD (San Francisco, CA)
Due to paucity of studies, a phase II clinical trial was undertaken to correlate the intensity of 5-aminolevulinic acid (ALA) fluorescence with degree of tumor cellularity during resection of high grade gliomas.
A single-center, single arm, phase II clinical trial of ALA fluorescence-guided resection of high grade gliomas was held from August 2010 to February 2014. Biopsies were graded on a 4 point scale (0-none to 3-highest) based on ALA fluorescence intensity by the neurosurgeon and independently based on tumor cellularity by a neuropathologist. Outcome of interest was the correlation of ALA fluorescence intensity to tumor cellularity and adverse events.
A total of 211 biopsies from 59 patients were included: 79.7% glioblastoma. ALA intensity 3 correlated with tumor presence 97.4% of cases and ALA intensity 0 correlated with tumor absence 93.0% of cases. For all tumor types, glioblastoma, high grade, and recurrent tumors, ALA fluorescence intensity 3 correlated strongly with cellularity grade 3; correlation coefficients were 0.65, 0.66, 0.65, and 0.62, respectively. Specificity and PPV of ALA intensity 3–cellularity grade 3 match ranged from 95% to 100% and 86% to 100%, respectively. In samples without tumor, 35.4% had ALA fluorescence. Of those, 90.9% contained reactive astrocytes and atypical cells; 8.1% were normal brain. In non-fluorescent samples, 62.3% had tumor cells present. ALA associated complication was 1.7%.
ALA demonstrated high PPV and NPV, and ALA intensity 3 correlated strongly with cellularity grade 3. However, even in the absence of tumor cells, reactive changes including inflammation may lead to ALA fluorescence.
Article ID: AA-31547