TUMOR MARKER "CA15-3" IN BREAST CANCER

The clinical significance of breast cancer-related antigen CA15-3 and its relationship with CEA are examined. Subjects are 328 cases comprising of 90 of primary breast cancer, 28 of relapsed breast cancer, 66 of postoperative and non-relapsed breast cancer, 46 of benign mammary glandular diseases, 59 of other organic cancers, 16 of puerperae and 23 of healthy females. When CA15-3 levels more than 25U/ml were regarded as positive, the positive rate was as low as 13.7% or 33.3% for stage I or stage II cancer respectively, so that CA15-3 might not be a possible candidate for screening marker. However, significant high levels of serum CA15-3 and the positive rate in cases above n1β indicated the usefulness of CA15-3 as an index of biological malignancy. CA15-3-positive was rated as igh as 79.3% for relapsed breast cancer, indicating a favorable feature of CA15-3 as monitoring marker for postoperative relapse. Moreover, well-coincided variation of serum CA15-3 with therapeutic effects in advanced or relapsed cancers revealed that CA15-3 was a valuable index in judging therapeutic efficacy. In terms of relationship between CA15-3 and CEA, correlation coefficient between the both was as low as r=0.287 for relapsed breast cancer, suggesting a greater effectiveness of combination assay with CA15-3 and CEA as postoperative monitoring. CA15-3 appears to be as the same substance as antigen DF3, and immunohistochemical assay revealed that antigen DF3 localized in the cytoplasm of breast cancer cells.