ERCC4 and ovarian carcinoma: Focusing on high-grade serous/endometrioid PDXs, as they account for 80% of ovarian carcinomas and the majority of our OC-PDX samples, only the correlation between the ERCC1 IHC-score with XPF mRNA was maintained (Spearman correlation coefficient 0.69, p = 0.0001, Table 2).