Combination of cancer antigen 125 and carcinoembryonic antigen can improve ovarian cancer diagnosis.

Introduction The purpose of the present study was to evaluate the ability of the tumour marker carcinoembryonic antigen (CEA) in combination with cancer antigen 125 (CA-125) to differentiate between malignant ovarian and malignant non-ovarian disease. Material and methods All patients attending the Department of Gynaecology, Herlev Hospital, who underwent an ovary lab investigation between 1 January 2006 and 31 December 2008 were included. Among a total of 640 patients, 355 had a malignant diagnosis. Preoperative CEA and CA-125 serum levels and final malignant diagnosis after surgery were extracted from the medical records. Results Among the patients with CEA levels > 5 ng/ml, 68% had non-ovarian malignancies. This test identified 39% of the non-ovarian cancers correctly. In patients with a CA-125/CEA ratio > 25, an ovarian cancer was found in 82%. The CA-125/CEA test identified 63% of the non-ovarian cancers correctly. The specificity increased to around 85% when the cut-off value of the CA-125/CEA ratio was increased from 25 to 100. Conclusion In patients with an undiagnosed tumour in the pelvis, the CA-125/CEA ratio may be used to preoperatively identify a substantial fraction of patients with non-ovarian malignancies. In the study population, the specificity rose to 85% when the cut-off value was increased from 25 to 100, which highlights the usefulness of a higher cut-off level. Funding not relevant. Trial registration not relevant.