Preliminary Study on Serum Levels of Mucinous like Cancer Antigen (MCA) in Patients with Breast Disease: Comparison with CEA

Evaluation of the Expression of Tissue DF-3 and MCA and the Corresponding Serum Values in Patients with Breast Carcinoma

Two specific monoclonal antibodies for breast tissue (DF3 and MCAb-12) and the corresponding tumor markers CA15-3 and MCA in serum have been evaluated in 50 patients with breast cancer and in 15 controls. The expression of these antigens in tissue was poorly correlated with the common prognostic parameters. Their presence in serum was associated with an altered distribution of the antigens in the cell. The expression of these antigens in tissue enables us to select patients for serological follow-up and to evaluate tumor differentiation from a functional point of view.

Mucin-Like Carcinoma-Associated Antigen (MCA) in Breast Cancer: Clinical Experience at the National Cancer Institute of Milan

Mucin-like Carcinoma-associated Antigen (MCA) is a glycoprotein belonging to the mucin family; it is defined by the monoclonal antibody b-12. Mucins represent an interesting group of tumor markers and are widely utilized in the clinical monitoring of neoplastic patients. These molecules show a certain degree of tissue specificity and MCA is preferentially associated with breast tissue.

Several studies have demonstrated that patients with breast cancer usually have high MCA serum levels. In this paper the experience of the National Cancer Institute of Milan with the clinical use of MCA in breast cancer patients is reported. The observed sensitivity of the MCA test was poor in patients with early-stage disease, while it was acceptable in patients with advanced breast cancer. MCA concentrations appeared to be directly related to disease spread. A clear relationship was seen between MCA levels and lymph-nodal status. The highest MCA plasma levels were observed in patients with metastatic disease. In this group of patients the sensitivity of the test on the basis of a cut-off of 11 U/mL was 52%.

Tumor Markers In Biological Fluids Associated With Pregnancy

Proteins that are expressed by both malignant and healthy fetal tissues are recognized as oncofetal. These antigens are associated with cell proliferation and differentiation and are produced in high concentrations in pregnancy and malignancy. Their biological role in malignancy is the suppression of the host's immune system, while in pregnancy they affect the maternal immune response, generating maternal tolerance toward the embryo. This review describes the levels of alpha-fetoprotein (AFP), human chorionic gonadotropin (hCG), carcinoembryonic antigen (CEA), cancer antigen 125 (CA 125), squamous cell carcinoma antigen (SCC), cancer antigen 15-3 (CA 15-3), mucin-like carcinoma-associated antigen (MCA), tissue polypeptide-specific antigen (TPS), carbohydrate antigen 19-9 (CA 19-9), and prostate-specific antigen (PSA) in maternal serum (MS), umbilical cord serum (UC), and amniotic fluid (AF) and outlines their roles in the assessment of pregnancy and malignancy. All antigens studied, except CA 15-3, are oncofetal. The presence of considerable concentrations of AFP, hCG, CEA, CA125, SCC, MCA, TPS, CA 19-9, and PSA in AF during pregnancy may be attributed to their involvement in biological functions associated with fetal development, differentiation, and maturation. MS CEA, CA 15-3, and CA 19-9, in contrast to all the others, are not influenced significantly by pregnancy and thus remain reliable tumor markers in monitoring malignancy in pregnant patients.

Mucin-like carcinoma-associated antigen (MCA) during normal pregnancy

OBJECTIVE

To assess the usefulness of Mucin-like carcinoma-associated antigen (MCA) in monitoring pregnant patients with breast cancer.

STUDY DESIGN

Maternal serum (MS) and amniotic fluid (AF) antigen values were measured by an enzyme immunoassay in 30 pregnant women during the second trimester, in 28 during the third and in 26 at parturition. Sera only from 26 women in the first trimester and from 26 healthy, non-pregnant women (controls) were also analyzed.

RESULTS

Maternal serum MCA concentrations increased significantly with gestational age (p<0.0001). The frequency of elevated serum values was 5% in the first, 35% in the second and 100% in the third trimester and at parturition. Antigen values in AF were markedly higher than those in MS (p<0.0001) and increased also significantly with advancing gestation (p<0.0001). A strong correlation was observed between MS and AF antigen values (r=0.77, p<0.0001). Maternal serum values at parturition were dependent on the mode of delivery, being higher in the cases who delivered vaginally, compared to those delivered by elective caesarean section (p<0.006).

CONCLUSION

Our data suggest that pregnancy affects significantly maternal serum MCA. Consequently, MCA seems to be a non-reliable marker in monitoring pregnant patients.

Clinical evaluation of potential usefulness of CEA, CA 15-3, and MCA in follow-up of breast cancer patients

The potential usefulness of MCA, CA 15-3 and CEA in monitoring of breast cancer patients was evaluated in 135 female patients with histologically confirmed breast cancer. The patients were classified into two groups as follows: group of patients with no evidence of disease, NED; and group of patients with progressive disease, PD. In total, 2106 measurements of CEA, CA 15-3, and MCA were performed using an enzyme immunoassay. Serum levels of all three markers in the NED group differed significantly from those of patients with PD. The observed differences in the sensitivity and specificity of CEA, CA 15-3, and MCA tests were not significant. The serum concentrations of a particular marker correlated well with the concentrations of the other two markers, except when CEA was correlated with MCA or CA 15-3 in NED group patients. The elevation of tumor markers preceded by some 7 months the clinical evidence of dissemination, and marker levels reflected at a high percentage the response to therapy in PD patients. Therefore, this clinical study confirmed that MCA, CA 15-3 and also CEA are suited to discriminate between disease and disease-free periods, and also validated the usefulness of markers for treatment response monitoring.