The cyst wall in this mucinous cystadenoma shows papillary formations and simple glands. The lining epithelium is intestinal type with numerous goblet cells. The epithelial lining of ovarian mucinous tumors may resemble that seen in endocervix, gastric pylorus, or intestine. Glands and cysts may occasionally rupture with extravasation of mucin. This is usually accompanied by inflammation and/or granulomatous stromal response. About 10% of mucinous cystadenomas of the ovary are associated with a dermoid cyst or a Brenner tumor. KRAS mutations are found in almost 60% of cases.