Abstract
Background: The 5th edition of the World Health Organization Classification of Tumors of the CNS introduced a subclassification of tumors based on key molecular markers. In adult-type diffuse gliomas, isocitrate dehydrogenase (IDH) and telomerase reverse transcriptase (TERT) promoter mutations play pivotal roles in the molecular classification. This study developed a rapid genotyping system using GeneSoC, a real-time PCR platform with microfluidic thermal cycling capable of completing 50 cycles of PCR within 20 min. Methods: To establish optimal analytical conditions, frozen tumor tissues from 67 patients and artificial DNA vectors were analyzed using this system. This system demonstrated a detection limit of at least 5% variant allele frequency for the IDH1 R132H and TERT promoter C228T/C250T mutations. Subsequently, intraoperative testing was performed in 120 cases using this system. Results: The sensitivity and specificity of IDH1 R132H mutation were 0.985 and 0.982, respectively, whereas those of TERT promoter C228T/C250T mutation were 1.000 and 1.000, respectively. These mutations were detected intraoperatively within approximately 25 min after tumor tissue collection. Furthermore, this assay identified tumor boundaries in an IDH-mutated glioma case, where IDH1 R132H mutations could not be detected. Conclusions: The GeneSoC®︎-based rapid genotyping system may be effective not only for intraoperative diagnosis of diffuse glioma but also for detecting tumor boundaries.