CEACAM5 and ovarian cancer: Other papers suggest including other biomarkers, such as CA-19-9 and carcinoembryonic antigen, to separate primary ovarian cancer from gastrointestinal cancer or pancreatic cancer in the investigation of patients with unknown ovarian masses,2,3,24 especially if they have a previous history of malignant disease, as we found that metastasis to the ovary can occur up to 11 years after the original cancer diagnosis.