[Tumor markers of ovarian cancer]

Many of the recently developed tumor markers are carbohydrate antigens, and are clinically useful for the diagnosis of ovarian cancers. These carbohydrate antigens can be classified into three major categories; core protein-related antigens (CP-RA), core of carbohydrate chain-related antigens (CSC-RA) and periphery of carbohydrate chain-related antigens (PSC-RA). CA125, CA602, and CA130 belong to CP-RA; CA602, CA72-4, and sialyl Tn to CSC-RA; and CA19-9 and sialyl LewisX (SLX), to PSC-RA. The positive rates of CP-RA in the sera of patients with ovarian epithelial cancers are usually very high except in the case of mucinous cystadenocarcinomas. Meanwhile, those of CSC-RA are higher than those of CP-RA in the sera of mucinous cystadenocarcinoma patients, and the false-positive rate of CSC-RA is lower than that of CP-RA in benign ovarian tumors. The diagnostic efficiency of PSC-RA is inferior to that of CA-RA and CSC-RA. Multi-variate analysis has revealed that the combination assay of these CP-RA and CSC-RA markers is the most effective among the carbohydrate antigen assays for the diagnosis of epithelial ovarian cancers. beta-core fragment (beta-CF), a fragment of the hCG beta-subunit missing its carboxyterminal peptide, is often detected in the urine of ovarian cancers, indicating that urine can be a good sample source for ovarian cancer detection.