KRAS mutations have been reported to be present in 16 to 41% of cases of low grade serous carcinoma of the ovary. The prognostic significance of KRAS mutations in ovarian tumors is uncertain; some reports suggest that patients with KRAS G12V may have shorter overall survival than patients without mutation, while other reports suggest that KRAS mutations in some low grade carcinomas of the ovary may be associated with slightly improved prognosis. In-vitro studies showed that cell lines with KRAS G12V mutation are more sensitive to selumetinib (MEK inhibitor) compared to cells with KRAS G12D. The clinical response to MEK inhibitors in patients with these tumors and mutations remains to be elucidated.