trending toward significancep = 0.070
Significantly different mutation frequencies between all four subgroups were found in TP53 ( p ≤ 0.001), RB1 ( p = 0.024), HRAS ( p = 0.043), and FAT1 ( p = 0.040), and trending toward significance were PIK3R1 ( p = 0.070), TP63 ( p = 0.060), and NOTCH1 ( p = 0.085) (Figure 3 ).