Biochemical markers in ovarian cancer: possibilities and limitations

Cancer of the ovary is the commonest cause of death from gynaecological neoplasms. As ovarian tumours are relatively inaccessible, there is a great need for methods to improve early diagnosis and to assist with the management of patients with this disease. In this presentation the state of the art is discussed with regard to the usefulness of the presently recognised 'tumour antigens' and other biochemical markers in ovarian cancer. Of the oncodevelopmental antigens, only alpha fetoprotein and chorionic gonadotropin are well established as good markers in tumours with, respectively, yolk sac and trophoblastic elements. Carcinoembryonic antigen seems from our own experience to be an unreliable marker in cancer of the ovary. In epithelial tumours, which constitute the majority of ovarian malignancies, mostly serous and mucinous cystadenocarcinomas, some tumour products have been described, which may have potential as a marker, for example, ovarian cancer associated antigens, some glycoprotein glycosyltransferases, and also carcinoplacental alkaline phosphatases (CPAP). Recently, in patients with epithelial ovarian tumours attending our institute, multiple biochemical markers have been studied, including CPAP, phosphohexose isomerase, and some acute phase reactant proteins. The preliminary results which will be discussed, show that longitudinal studies of some of these markers could have clinical application in follow-up. It must be concluded that, in spite of all efforts so far, and although some markers may become useful, early detection of ovarian cancer is a goal still to be reached by clinical chemistry in the field of oncology.