BRAF and mucinous adenocarcinoma: Borderline tumors begin as ovarian surface epithelium and progress to low-grade serous, endometrioid, clear cell, and mucinous carcinomas by mutation and change of certain genes such as KRAS, BRAF, NRAS, HER2, CTNNB1, BRAF, ERBB2, ARID1A, PIK3CA, PTEN, HER2, and others.