The frequency of somatic aberrations in each of the most commonly mutated LGSOC driver genes (KRAS, BRAF, NRAS, and USP9X) were similar between ER-low and ER-high cancers with the exception of a higher frequency of PLEC mutations (19% versus 0%, p = 0.037; two-tailed test), although this difference was not significant after multiple testing correction (p = 0.480; Benjamini Hochberg correction) (Table 3). Here, USP9X is linked to cancer.