CA15.3, MCA, CAM26, CAM29 are members of a polymorphic family of mucin-like glycoproteins

The monoclonal antibodies that define the tumor markers CA15.3, MCA, CAM26 and CAM29 were found to react with coexisting epitopes present on mucin-like glycoproteins. Despite their immunologic relationship, the markers showed distinct concentration levels in various body fluids. Particularly, MCA and CAM26 were high in urine and amniotic fluid. Sera collected from pregnant or lactating women and especially human milk samples contained considerable amounts of CAM29 and MCA, but comparably small quantities of CAM26 and CA15.3. The concentrations of CA15.3, MCA, CAM26 and CAM29 were correlated in serum samples from patients with metastatic breast cancer. The discrepancy between immunologic relationship and dissimilar biologic behavior could be explained by a limited coexistence of epitopes on subsets of heterogeneous polymorphic mucins. All mucin markers which were investigated showed improved sensitivity for metastatic breast cancer compared with the established marker CEA.     

Pretreatment concentrations of breast carcinoma antigen (CA 15.3) and mucin-like carcinoma-associated antigen in patients with carcinoma of the breast

Pretreatment serum concentrations of breast carcinoma antigen (CA 15.3) and mucin-like carcinoma-associated antigen (MCA) were determined in 129 patients with breast carcinoma. Concentrations of both markers were within the normal range in patients with Stage I disease. Concentrations of CA 15.3 were elevated (greater than 40 U/ml) in 3, 11 and 48%, those of MCA (greater than 17 U/ml) in 11, 18 and 52%, and those of one or the other marker in 11, 18 and 58% of the patients with Stage II, III and IV disease, respectively. The elevation of either marker roughly paralleled the size of the tumor being normal in the patients with localized cancer, slightly elevated in a small proportion of the patients with locoregional cancer, and moderately to markedly elevated in half of the patients with distant metastases. Correlation between serum concentrations of CA 15.3 and MCA was highly significant (p less than 0.0001). It is concluded that the markers were equally sensitive and that an elevated serum level was a useful adjunct for staging, implying systemic disease.     

Follow-up of metastatic breast cancer patients with a mucin-like carcinoma-associated antigen: comparison to CA 15.3 and carcinoembryonic antigen

During a follow-up program, breast cancer patients were monitored with serum analyses of mucin-like carcinoma-associated antigen (MCA), CA 15.3 and carcinoembryonic antigen (CEA). Minimum as well as maximum marker values of the individual patterns were selected for further evaluation. Marker levels of risk patients differed significantly from those of patients with metastases. In several risk patients, elevated marker levels (especially of MCA) preceded clinical diagnosis of metastases for several months. In cases with already diagnosed metastases, sensitivity of MCA was comparable to CA 15.3 or CEA. The type of metastases determined marker sensitivity, concentration and the difference between maximum and minimum values.     

Diagnostic value of mucin-like carcinoma-associated antigen (MCA) in breast cancer

The diagnostic value of mucin-like carcinoma-associated antigen (MCA) was compared to that of carcinoembryonic antigen (CEA) and/or CA 15.3 in patients with breast cancer. A total of 368 patients with breast cancer were studied, of whom 253 were free of metastases, whereas 94 had either skeletal or visceral metastases or diffuse metastatic disease. The diagnostic sensitivity of MCA proved to be comparable to that of CA 15.3 and superior to that of CEA in patients with metastatic breast cancer. In contrast, the specificity of MCA was superior to that of CA 15.3. Finally, the diagnostic sensitivity of each of the tested tumour markers, i.e. MCA, CEA and CA 15.3, could be improved by their combined use. We conclude that MCA, either alone or in combination with CA 15.3 and CEA, can improve the monitoring of disease progression in patients with metastatic breast cancer.     

Treatment of disease-negative but mucin-like carcinoma-associated antigen-positive breast cancer patients with tamoxifen: preliminary results of a prospective controlled randomized trial

Increasing levels of tumor markers such as carcinoembryonic antigen, mucin-like carcinoma-associated antigen (MCA), CA 15.3, and monoclonal antibody H23 in breast cancer patients following the treatment of the primary disease and adjuvant radiation and chemotherapy reflect subclinical development of metastatic disease. Overt metastatic disease is usually incurable and prolongation of life at this stage is impossible, and the treatment is only palliative. The efficacy of tamoxifen, a least-toxic agent, in the treatment of early and minimal metastatic disease detected only by increasing serum levels of MCA was studied prospectively in a randomized study. Our preliminary, albeit encouraging, results showed that the rate of relapse within a median follow-up period of 11 months was 24.1% in the control arm as compared with 0% in the tamoxifen arm (Fisher's exact test,P=0.012). None of the patients with a relapse had positive progesterone receptors (PR). We may carefully conclude that early treatment may be warranted in young patients with negative PR and continuously increasing serum levels of the marker.     

Intensive post-operative follow-up of breast cancer patients with tumour markers: CEA, TPA or CA15.3 vs MCA and MCA-CA15.3 vs CEA-TPA-CA15.3 panel in the early detection of distant metastases

Background  

In breast cancer current guidelines do not recommend the routine use of serum tumour markers. Differently, we observed that CEA-TPA-CA15.3 (carcinoembryonic (CEA) tissue polypeptide (TPA) and cancer associated 115D8/DF3 (CA15.3) antigens) panel permits early detection and treatment for most relapsing patients. As high sensitivity and specificity and different cut-off values have been reported for mucin-like carcinoma associated antigen (MCA), we compared MCA with the above mentioned tumour markers and MCA-CA15.3 with the CEA-TPA-CA15.3 panel.     

An evaluation of the usefulness of primary tumour expression of MCA and CA15-3 as prognostic indicators in breast carcinoma.

CA15-3 antigen and mucin-like carcinoma associated antigen (MCA) show potential as clinically useful serum markers of breast carcinoma. Recently, immunohistochemical versions of these monoclonal antibodies have become available but few data are available as to their clinical usefulness. The aims of this study were (i) to assess CA15-3 and MCA expression by primary breast tumours and to correlate tumour immunoreactivity with tumour behaviour, and (ii) to investigate the relationship between immunohistological staining and oestrogen receptor (ER) status. Pathological material from 39 stage 1 (node free) breast carcinoma patients was assessed. The mean age was 51.3 (range 34-70) years, 19 were premenopausal and the mean duration of follow-up was 3.6 years (range 0.8-14 years). In each case two further sections were stained with antisera to the CA15-3 and MCA antigens. Staining of primary tumour was achieved in 38 cases. Low (less than 30% tumour cell staining) and intermediate (30-60% of cells staining) grade immunoreactivity with both monoclonals correlated with significantly shorter disease free intervals (P less than 0.05). Neither monoclonal can predict ER status. We conclude that the use of monoclonal antibodies to CA15-3 and MCA in staining primary breast carcinoma tumours and their axillary nodes may be a significant (P less than 0.05) prognostic indicator of future tumour behaviour and that this requires further evaluation.     

Is tissue polypeptide antigen still a useful tumor marker in breast carcinoma? Comparison with CA15.3 and MCA

Serum levels of tissue polypeptide antigen (TPA) are related to the proliferative activity and to the mass of the malignancy, differently from any other available tumor marker. We therefore evaluated TPA in comparison with CA15.3 and MCA (mucinous-like carcinoma-associated antigen) in patients with primary breast cancer. TPA was measured in tumor cytosol and in serum. Cytosol and serum TPA levels were not significantly correlated. Serum TPA was higher in patients with locally more advanced disease and in receptor-negative cases. The relation between TPA and disease spread was not directly dependent on tumor bulk, whereas CA15.3 and MCA were highly correlated to the number of positive lymph nodes and tumor size. No correlations were found between TPA and CA15.3 or MCA, and the positivity concordance rate between TPA and CA15.3 or MCA was very low. Patients with higher TPA serum levels showed a worse prognosis in cases with and in those without axillary metastases. From our data we conclude that TPA provides information different from that obtained with breast-specific tumor markers and could therefore be useful in association with CA15.3 and/or MCA in the management of patients with breast cancer.     

CA 15.3: early results of a new breast cancer marker

A new antigen associated with breast cancer, CA 15.3, was determined in the serum of 690 breast cancer patients and controls. After establishing a maximum normal level of 40 U/ml in 140 healthy subjects and 350 patients with benign diseases, CA 15.3 was investigated in 190 breast cancer patients: CA 15.3 serum levels were statistically different in patients with no evidence of disease (20.6 +/- 11.2 U/ml), metastatic patients in response (33.5 +/- 24.0 U/ml) and metastatic patients not responding to therapy (stable disease, 98.9 +/- 50.4; progression, greater than 200). CA 15.3 serum levels seem to correlate with the extent of metastatic breast cancer. Further studies are needed to establish the role of this marker in the management of breast cancer patients.     

Comparison of breast cancer mucin (BCM) and CA 15-3 in human breast cancer

Summary The Breast Cancer Mucin (BCM) enzyme immunoassay utilizes two monoclonal antibodies (Mab), M85/34 and F36/22, for the identification of a mucin-like glycoprotein in serum of breast cancer patients. We have compared BCM with CA 15-3, another member of the human mammary epithelial antigen family.Serum BCM was evaluated in 151 and CA 15-3 in 134 patients with breast cancer, in 30 normal controls, in 9 pregnant women, and in 13 cancer patients (non-breast). Neither the normal controls nor the pregnant women had BCM levels > 25 U/ml. In contrast, 87 of 115 patients (75%) with metastatic breast cancer had BCM levels > 25 U/ml. All control persons had CA 15-3 levels < 25 U/ml, but 2 out of 9 pregnant women (22%) had levels > 25 U/ml. Seventy-four out of 97 patients (76%) with metastatic breast cancer had CA 15-3 levels > 25 U/ml.A statistically significant correlation was found between BCM and CA 15-3 in the breast cancer patient group (r = 0.883, p < 0.001, n = 134) and in the normal control group (r = 0.743, p < 0.001, n = 30). BCM and CA 15.3 both showed no correlation with CEA in breast cancer patients (r = 0.060, n = 81; and r = 0.146, n = 78, respectively). BCM had a range of sensitivity similar to that of the CA 15-3 RIA.Our results suggest that BCM may be a useful new marker for monitoring the clinical course of patients with breast cancer. Furthermore, in the evaluation of breast cancer patients, marker pands depending on disease stage may be a better choice than any single parameter in the evaluation of breast cancer patients.     

Preoperative CA 15.3 and prognosis in primary breast cancer

CA15.3 is a breast cancer-associated antigen encoded by the MUC-1 gene. The clinical applications of CA 15.3 are the monitoring of response in advanced breast carcinoma and the early detection of recurrences. We have investigated the prognostic value of CA 15.3 in primary breast cancer. Preoperative serum CA 15.3 was measured in 478 patients with early breast cancer. Positive CA 15.3 was defined as > 30 U/ml. CA 15.3 positivity was correlated with patient outcome in terms of disease-free survival (DFS). Seven per cent of patients had elevated serum CA 15.3. A positive association was found between CA 15.3 positivity and tumour size. Twenty-one per cent of the patients with T3 and T4 tumours had high serum concentrations of CA 15.3; while only six per cent of patients with T1 and T2 tumours had elevated concentrations of CA 15.3 (p < 0.0001). There was no correlation between CA 15.3 serum levels and menopausal status, axilary lymph node status, estrogen receptor status, p53 and erbB-2 status, and CEA serum levels. With a median follow-up of 24 months, we found that elevated CA 15.3 levels predicted a poor clinical outcome. The probability of disease-free survival at two years was 73% in patients with high preoperative CA 15.3 compared with 90% in patients with normal CA 15.3 levels (logrank p = 0.003). The association of CA 15.3 with DFS was also analysed with a Cox analysis, and was found to be independent of tumour size. The multivariate analysis showed that poor disease-free survival was significantly associated with high CA 15.3 (p = 0.04), large tumour size (p = 0.001), estrogen receptor negative status (p = 0.008), overexpression of erbB-2 (p = 0.04), and overexpression of p53 protein (p = 0.03). Preoperative serum CA 15.3 is significantly related to clinical outcome in patients with early breast cancer. High CA 15.3 indicates a poor prognosis and this is independent from tumour size. Whether the poor prognosis associated with CA 15.3 is related with the role of mucins in the adhesion of cancer cells needs to be investigated.     

Elevated levels of a high molecular weight antigen detected by antibody W1 in sera from breast cancer patients

A novel screening assay was used to test 13 previously described antibreast cancer antibodies for those which recognize antigens elevated in serum of breast cancer patients. Binding of three of these antibodies to breast or lung carcinoma cells was inhibited to a significantly greater extent by tumor patient serum than by normal serum, suggesting that the antigens might be useful serum markers. Two of these antibodies, W1 and W9, were shown to recognize nonoverlapping epitopes on a high molecular weight molecule(s) purified from serum from breast cancer patients. A sensitive double determinant immunoassay was developed to measure W1 antigen levels in sera from a total of 389 cancer patients and controls. Forty seven % (37 of 79) of individuals having breast cancer showed elevated serum levels of the W1 antigen, whereas only 4% (1 of 25) of normal controls and 2% (1 of 47) of patients hospitalized for nonmalignant disorders showed elevated levels. These differences were statistically significant (P less than 0.001). The percentage of breast cancer patients showing elevated serum levels was greater for individuals with metastatic disease. Statistically significant numbers of lung, ovarian, and prostate, but not colon, cancer patients also had elevated serum levels of the W1 antigen. These data suggest that measurement of the W1 antigen in serum might provide clinically useful information on the course of metastatic breast and other cancers.     

Clinical Evaluation of an Immunoradiometric Assay for CA15-3 Antigen Associated With Human Mammary Carcinomas: Comparison With Carcinoembryonic Antigen

Serum levels of CA15-3, a mammary tumor associated antigen recognizedby two different murine monoclonal antibodies (115D8 and DF3),were investigated in patients with mammary carcinoma and otherbenign or malignant diseases. The reference value of the serumCA15-3 level was obtained as 24 units/ml at the 99% confidencelimit among healthy individuals (n = 462). Elevation of serumCA15-3 levels was observed in 24.3% of overall patients withmammary carcinoma. Serum CA15-3 levels in breast cancer patientscorrelated with the clinical stage; higher percentages of positivitywere observed in those with advanced breast cancer (stage IV,64.7%, recurrent, 52.4% and metastatic, 70.3%). Furthermore,elevated serum CA15-3 levels in breast cancer patients respondedwell to the effect of therapy. Although the serum CA15-3 testgave percentages of positivity of breast cancer similar to thosefound by the serum CEA test, the serum CA15-3 test revealedlower percentages of posi-tivity than the serum CEA test amongpatients with benign breast lesions, liver cirrhosis or othercarcinomas. These results suggest that the serum CA15-3 antigenlevel provides a very useful marker for diagnosis and clinicalmonitoring of patients with breast cancer.     

Relationship of carbohydrate antigen 19-9 and Lewis antigens in pancreatic cancer

Carbohydrate antigen (CA) 19-9 identified by a murine monoclonal antibody against a colorectal carcinoma antigen is thought to be a sialylated Lewis (Le)a blood group antigen and occurs in high concentration in serum of patients with pancreatic carcinoma. This study was designed to identify the relationship between Lewis antigens and CA 19-9 in patients with pancreatic cancer. The following analyses were performed in 20 pancreatic cancer patients: Lea and Leb antigen phenotype in saliva (modified enzyme-linked immunosorbent assay) or on red cells (hemagglutination); CA 19-9 levels (radioimmunoassay) in serum; and CA 19-9 and Lea and Leb expression (immunoperoxidase assay) on tumor tissue. Lea-b- patients based on salivary phenotype failed to express CA 19-9 in tumor tissue and had normal or low levels of CA 19-9 (less than 37 units/ml) in serum (P = 0.0011, versus Lea+b- and Lea-b+ patients). Eighty-eight % of Lea+b- and Lea-b+ patients had elevated serum CA 19-9 levels (greater than 37 units/ml). All Lea+b- and Lea-b+ patients expressed both Lea and Leb antigens in tumor tissue. These results support the view that Lea-b- pancreatic cancer patients cannot manufacture CA 19-9. Surprisingly, Lea-positive patients express Leb antigen in tumor tissue; in this subgroup, Leb antigen may be a tumor-specific biomarker.     

Detection of antigens recognized by a novel monoclonal antibody in tissue and serum from patients with breast cancer

Monoclonal antibodies were produced in mice immunized with proteins released into tissue culture fluid of human breast cancer cells maintained in vitro. One monoclonal antibody (SP-2) identified a Mr 90,000 antigen which appears to be a proteolipid. In immunoperoxidase assays, SP-2 reacted with 81 of 90 specimens of human breast cancer. It also reacted with 12 of 23 cancers of nonbreast origin but was unreactive with all normal tissues tested. The Mr 90,000 antigen, purified by immunoaffinity chromatography using SP-2, was used in an indirect binding inhibition assay for the detection of antigen in human serum. With this assay, 35 of 69 patients with breast cancer and 11 of 37 patients with benign breast lesions showed serum antigen levels above 6 units/ml. Patients with nonbreast cancers also demonstrated elevated levels of antigen in 32% of cases. The SP-2 defined Mr 90,000 antigen appeared to be distinct from carcinoembryonic antigen and other monoclonal antibody-defined breast cancer antigens of similar molecular weight. SP-2 may prove useful as a serum and/or tissue marker in breast pathology.     

Clinical value of a mucin-like carcinoma-associated antigen in monitoring breast cancer patients in comparison with CA 15-3

A new tumour marker, mucin-like carcinoma-associated antigen (MCA), was evaluated in 176 breast cancer patients classified either as free of tumour (NED, n = 141) or as having metastases (PD, n = 35). During the 5 year follow-up, 842 measurements of MCA and 363 measurements of CA 15-3 were done. MCA levels were significantly increased in the PD group (P = 0.0001) but not in the NED group. The sensitivities of the MCA and the CA 15-3 assays were 84% and 78% and the specificities were 81% and 78%, respectively. The negative predictive value of 97% for MCA was significantly higher (P = 0.0001) than the 88% for CA 15-3. Thus the MCA enzyme immunoassay is at least equivalent to the CA 15-3 test and is recommended in the assessment of metastatic spread or tumour recurrence in breast cancer patients.     

An evaluation of mucin-like carcinoma associated antigen (MCA) in breast cancer

Serum levels of mucin-like carcinoma associated antigen (MCA) were measured in 80 healthy women, 109 patients with breast cancer at presentation and in samples taken from 45 patients with active metastatic breast cancer. The MCA levels in controls had an upper limit of normal of 19.6 U ml-1 in post-menopausal and 16.4 U ml-1 in premenopausal women. The levels at presentation in stages I and II and III were not significantly different from the post-menopausal controls. Longitudinal studies over 5-9 years in 20 patients with stage I and II disease who had remained tumour-free showed a narrow MCA range for each individual patient, but the mean and range of a single measurement in a further 63 of these patients were similar to those of the normal controls. Rising MCA levels occurred in 12/14 patients who developed metastases in 2-8 years after surgery, but local recurrence was not associated with a rise of MCA. Eighty per cent of patients with active metastatic disease had MCA levels greater than 15 U ml-1. MCA levels fell during clinical responses to therapy in metastatic cancer. In the context of follow-up serum MCA levels appear to be a sensitive indicator of metastatic disease; caution is required in the interpretation of isolated measurements.     

Value of CA 15.3 in breast cancer and comparison with CEA and TPA: A study of specificity in disease-free follow-up patients and sensitivity in patients at diagnosis of the first metastasis

Summary The specificity and sensitivity of a tumor marker (TM) are important in establishing its potential clinical utility for a specific type of neoplasm. CA 15.3 is a TM specific for breast cancer; it is defined by two monoclonal antibodies (DF3 and 115D8), whose specificity, in disease-free follow-up patients, and sensitivity, in patients at diagnosis of first metastasis, have been evaluated in the present study and compared with those of carcinoembryonic antigen (CEA) and tissue polypeptide antigen (TPA).Serum concentrations of all three TMs were quantified in 618 individuals: 80 healthy controls, 421 patients with local breast cancer who became free of disease following locoregional treatment, and 117 patients with disseminated disease at diagnosis of metastasis. Radioimmunoassay (RIA) was the method employed, and the cut-off values obtained were 30 U/ml for CA 15.3, 5 ng/ml for CEA, and 120 U/I for TPA. The results showed CA 15.3 and CEA specificities to be analogous (95.7 and 95.5%, respectively). TPA specificity (81.9%) was lower (p<0.001). During adjuvant therapy, CA 15.3 serum levels were seen to increase, followed by a normalization of concentration after terminating therapy. On the other hand, CA 15.3 and TPA sensitivities (64.1 and 67.5%, respectively) were greater than for CEA (44.4%, p<0.01).It is concluded that CA 15.3 is a useful TM for breast cancer, as it offers a greater sensitivity than CEA and a higher specificity than TPA. Combining CA 15.3 and CEA fails to increase CA 15.3 sensitivity, while combining CA 15.3 with TPA increases false-positives and so likewise offers no additional benefit.     

A new biomarker in monitoring breast cancer: CA 549

Serum biomarkers are not very reliable in assessing outcome or predicting recurrence of breast cancer. Clinically, carcinoembryonic antigen (CEA) is widely used and is elevated in a majority of patients with metastatic breast cancer. However, it is falsely elevated in a wide range of nonmalignant conditions and correlates poorly with disease progression. We evaluated a newly described monoclonal antibody, CA 549, in an immunoradiometric assay which uses two monoclonal antibodies directed against tumor and milk fat globule membranes. CA 549 and CEA were studied in 682 patients, 331 of whom had breast diseases and 99 of whom were followed with multiple serum samples. Of 69 patients with benign breast diseases, 1.5% had elevated CA 549, 0% of 30 pregnant women had elevated CA 549, and 26% of patients with nonmalignant liver disease had CA 549 elevation. In metastatic cancer of prostate, ovary, endometrium, colon, and lung CA 549 was elevated in 12% to 50% of cases with levels less than 120 U/mL. In breast cancer, CA 549 was elevated in 11% of 88 patients who received adjuvant chemotherapy and had no evidence of metastasis; in 23% of 16 patients in complete remission after chemotherapy; in 63% of 52 patients in partial remission after therapy; and in 83% of 106 patients with progression of breast cancer compared with 63% with elevated CEA (P = .001). In diseases of the breast, CA 549 has a sensitivity In diseases of the breast, CA 549 has a sensitivity and specificity of 77% and 92% v 61% and 92% for CEA. Of 99 patients serially monitored with clinically documented breast cancer progression, regression, or stability of disease, CA 549 was statistically significantly superior to CEA in monitoring a greater than 25% change in those patients with metastatic progression (P = .03). CA 549 is a new serum marker that should be control tested in prospective clinical trials alone or in conjunction with other markers.