[Preclinical and clinical studies on a tumor marker, galactosyltransferase associated with tumor (GAT), in ovarian cancer (first report)--preclinical study of GAT assay kit and clinical study of normal level].

ABSTRACT

We conducted preclinical and clinical studies on GAT Galactosyltransferase Associated with Tumor, a newly developed tumor marker of ovarian carcinoma. This paper presents the results of evaluation of a GAT assay kit, the normal range of its values, and analysis of its value relative to age, menstrual cycle, and stage of pregnancy. Calibration curve, reproducibility, analytical recovery test, and dilution test all yielded favorable results, and the assay system was proved to be reliable in both precision and reproducibility. However, special attention must be paid to highly hemolytic samples because of a positive error in GAT value for samples with a high concentration of hemoglobin. The cut-off value was set at 16U/ml based on the mean+2SD of healthy females. A uniform cut-off value could be employed since neither age nor stage of menstrual cycle had any observable influence on the level. The positive rate for healthy subjects was 3.1%, when the cut-off value of 16 U/ml was used. On the other hand, elevation of the GAT value was observed during the progression of pregnancy.