This finding is consistent with the idea that most ovarian carcinomas originate from either the ovarian surface epithelium (mesothelium), the fallopian tubal epithelium, the epithelium lining ovarian inclusion cysts, or the endometrial epithelium of endometriosis tissues (all CK7/PAX8 double-positive) [22, 23]. The gene discussed is KRT7; the disease is endometriosis.