Correlation between FF and FFPE β values for individual methylation loci. For (A) and (B), each data point represents a single sample for which the β value of the FFPE is shown on the x-axis and the corresponding β value from FF is shown on the y-axis. Red points are tumor samples, and blue points are from normal samples. (A) A representative locus for which correlation between FF and FFPE samples was poor. (B) A representative locus for which correlation between FF and FFPE samples was good. (C) Histogram showing the distribution of resultant r values from FF/FFPE correlations for all loci.