Fig. 2

MGMTpromoter methylation trends in pyrosequencing samples. (A) Frequency of positive results for all glioma samples above and below the cutoff value of VAF = 0.325. (B) Cumulative mean frequency of positive test results as a function of VAF. (C) Trends in cumulative mean MGMT promoter pyrosequencing score with increasing VAF. (D) Mean MGMT promoter pyrosequencing scores above and below VAF = 0.325. Similar results are shown for each tumor subtype, including IDH-wildtype glioblastoma (E-H), IDH-mutant astrocytoma (I-L) and IDH-mutant and 1p/19q co-deleted oligodendroglioma (M-P). (Horizontal dashed black lines: mean values for cohort; Horizontal solid red lines: MGMT positivity cutoff of 10.0%; Vertical dashed black lines: cutoff values identified by Cutoff Finder; Vertical dashed red lines: cutoff values identified by multi-part linear regression; Panels A, E, I, M: Fisher’s exact test; Panels D, H, L, P: unpaired Student’s T-test; pyroseq: pyrosequencing; *p < 0.05; ****p < 0.0001)