Monoclonal antibodies against antigens on breast cancer cells

Localization of Mucinous - like Carcinoma Associated Antigen (MCA) in Breast Pathology: Comparison with Carcinoembryonic Antigen (CEA) and Tissue Polypeptide Antigen (TPA)

The topographic distribution of a mucinous-like cancer antigen (MCA) recognized by a monoclonal antibody b-12 (MAb b-12) was assessed in benign (38) and malignant (66) breast tissues. The reactivity of MAb b-12 showed a good selectivity for breast tissues, reacting both with normal tissues and breast cancer. The degree of MCA expression was evaluated in the various groups of breast pathology adopting quantitative criteria of assessment. With the criteria of evaluation adopted, strong staining was observed in 71.4% breast carcinomas. The most positive reaction was demonstrated in mucinous carcinoma.

MCA distribution in breast tissue was compared with the distribution of two other antigens, CEA and TPA. Reactivity of MAb b-12 was higher than the reactivity shown by the anti-CEA and anti-TPA antibodies.

MCA in Patients with Breast Cancer: Correlation with CEA and CA15-3

MCA serum levels were determined in 27 healthy subjects, 136 with benign pathology (42 breast) and in 289 patients with cancer (247 active). The last group includes 223 patients with breast cancer (96 without metastases, 89 with metastases and 38 no-evidence of disease). CEA and CA15-3 serum levels were determined in all the patients with breast diseases.

The mean levels of MCA were 4.7 + 2.4 U/ml in the control group, considering less than 11 U/ml as normal. MCA values were abnormal in 15.4 % of patients with benign pathology, mainly in those with liver cirrhosis (8/20) and lung diseases (4/20). In the majority of these cases, the rise was only moderate, lower than 15 U/ml in 97.5% of patients. In malignant diseases, important increments were found in breast cancer (19.8% Mo, 77.5% M1) and ovarian cancer stages III–IV (44.4%). When we compared MCA serum levels with CA15-3 and CEA in breast pathology, a similar specificity was observed: 92.3%, 92.3% and 100% in cases with benign pathology and 92.1%, 94.7%, and 97.4% in NED patients, respectively. MCA and CA15-3 sensitivity was similar in breast cancer without metastases (19.8%) and lower for CEA (16.7%). In patients with breast cancer without metastases, we found a relation between positivity of these tumor markers and prognostic factors (tumor size, nodal involvement). The disease free interval in patients with locoregional breast cancer was shorter in cases with abnormal presurgical levels of some of the tumor markers, but only the difference from MCA was significant (p < 0.02). Inpatients with metastases the sensitivity was about 77.5%, 70% and 65.1% respectively for MCA, CA15-3 and CEA. Sensitivity using the three tumor markers was not significantly better than with only two of them

Mucin-Like Carcinoma-Associated Antigen (MCA) in Tissue and Serum of Patients with Breast Cancer: Clinical Applications in Prognosis and Disease Monitoring

Mucin-like Carcinoma-associated Antigen (MCA) has been associated with many breast cancers. The aim of this study was to evaluate MCA in tumor tissue and serum as a potential tumor marker for prognosis and disease monitoring. MCA levels were determined in the tissue of 196 patients with primary breast cancer, 25 with metastatic disease and 25 patients with benign diseases, in pellet and/or cytosol. MCA levels were also determined in the serum of 50 patients with benign diseases, 148 with primary breast cancer (Mo), 150 with metastatic breast cancer (MT), and 200 with no clinical evidence of disease (NED). MCA tissue concentrations in pellet and cytosol were similar: 66.7 + 251 U/mg and 41.1 + 53 U/mg, respectively. No relationship between MCA levels and tumor size or nodal involvement was found. Higher MCA levels were observed in patients with ER + or PgR + tumors than in those with ER- or PgR- tumors (p < 0.01). Patients with MCA pellet concentrations lower than 10 U/mg of protein had shorter disease - free intervals (DFI) than those with higher values (p < 0.05).

Abnormally high serum levels of MCA were found in 8% of patients with benign diseases, 4% of NED patients, 22% of Mo patients, and in 76% of MT cases. In primary breast cancer MCA values were related to tumor size and nodal involvement. A trend toward a lower DFI in patients with elevated presurgical MCA levels was observed but was of no statistical significance. These differences became statistically significant when patients were subdivided according to nodal status, with shorter DFI in those without nodal invasion (p < 0.05). In metastatic patients, changes in serum MCA were related to the tumor's response to treatment in 82% of cases. The highest MCA values were found in patients with liver or bone metastasis and the lowest values were found in those with locoregional recurrence. In conclusion, although MCA is not a specific tumor marker, it can be useful as a prognostic factor (tissue and serum) and in monitoring metastatic patients.

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.

Biochemistry and Molecular Biology of MCA

The mucin-like carcinoma-associated antigen (MCA) is a mucin with a molecular weight of 350 - 500 kD. It circulates in the serum and its serum content can be determined with the Cobas Core MCA EIA test. Patients with breast cancer show elevated MCA serum levels. The molecule has a polypeptide backbone consisting of three parts: the C-terminus the N-terminus and the transmembrane sequences. The protein is heavily glucosylated with carbohydrate side chains that contain fucose, galactose and N-acetyl galactosamine. The antibody b-12 recognizes a repetitive epitope on the peptide portion of the MCA molecule. The epithelial mucin, which is coded by a unique gene, was cloned using PCR technology. Peptides corresponding to the N- and C-terminus were expressed in E. coli. Analysis of the purified peptides revealed molecular weights of 12 and 18 kD.

Immunohistochemical Distribution of Mucinous-like Carcinoma Associated Antigen (MCA) in Breast and Non-breast Cancer: Comparison with other Biological Parameters

The present study reports the immunohistochemical reactivity of the monoclonal antibody b-12 (MAb b-12) with malignant human tissues. 173 neoplastic tissues were tested: MAb b-12 stained all breast carcinomas independently of their histology, with different patterns within the various type of cancer. Some other carcinomas (stomach, bowel, ovary, lung, endometrium), were also reactive even if the fraction of positive cells was lower.

A comparison between the histological localization of MCA and that of CEA was performed; anti-CEA antibodies stained the cancer tissues with different reactivity and showed different percentages of positivity. MCA expression was also compared with other biological parameters such as the presence of estrogen receptors (ER), progesterone receptors (PgR), epithelial growth factor receptors (EGF-R), and oncoprotein p-53 which is encoded by the oncogene N-myc. The proliferative activity was also evaluated by measuring the growth fraction (GF) using the antibody Ki67. Any correlation was demonstrated between MCA and these parameters except for growth fraction as revealed by Ki67 antibody.

Clinical Value of a Mucin-Like Carcinoma-Associated Antigen (MCA) in Patients with Carcinomas of the Kidney and the Urinary Collecting System

A new tumor marker, mucin-like carcinoma-associated antigen (MCA), was evaluated in thirty-four patients with renal cell carcinomas andforty patients with carinomas of the urinary collecting system. In the first group, specificity was 95%, sensitivity 65%, the predictive value for positive diagnosis was 94%, andfor negative diagnosis 72%. In the second group specificity was 83%, sensitivity 71%, predictive value for positive diagnosis was 63%, and for negative diagnosis 88%. Receiver operating characteristic curves indicated that the maximum amount of information was greater in patients of the first group than the second (0.379 vs. 0.332 bits). In the light of these data, the MCA test can be recommended for assessing metastatic spread in patients particularly with renal cell carcinomas.

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

MCA (mucinous-like cancer antigen) can be measured in the biological fluids of patients by means of a solid phase enzyme immunoassay. This study describes the results of MCA determination in sera of 230 patients with benign (99) and malignant (131) breast diseases. MCA levels were significantly higher in breast cancer patients than in non cancer patients and in healthy subjects (p < 0.001). MCA concentrations tended to increase as the stage of the disease advanced. The 95th percentile of MCA value distribution in normal subjects showed a diagnostic sensitivity in breast cancer patients of 16.3% at stage I,26.2% at stages II-III and 52% at stage IV. In a group of 118 cancer patients, MCA and CEA were tested simultaneously. The diagnostic sensitivity and specificity of MCA and CEA assays was very similar; nevertheless the association of the two tests showed 11 cases with high levels of MCA and low levels of CEA and 9 patients with high levels of CEA and low levels of MCA. Seventy-four out of 118 patients were negative for both markers and in 22 out of 118 patients markers were positive. The new marker MCA appeared to correlate with breast cancer and gave different information complementary to CEA.

Demonstration of Mucinous-Like Carcinoma-Associated Antigen in Bone Marrow and Lymph Node Biopsies from Patients with Breast Carcinoma

Two hundred and fifty bone marrow and 140 lymph nodal biopsies were analyzed immunocytochemically, using a mouse monoclonal antibody b-12 (MAb b-12), which reacts with MCA (mucinous-like carcinoma-associated antigen). The presence of MCA in bone marrow specimens was demonstrated in 102 out of 105 (97.1%) breast cancer metastases, 5 out of 8 (62.5%) gastric cancers, 5 out of 6 (83.3%) colon cancers, 3 out of 5 (60%) prostate cancers, 11 out of 26 (42.3%) lung cancers and 25 out of 30 (83.3%) unknown primary cancers, while no positivity to anti-MCA antibody was found in 30 cases of normal bone marrow biopsies, 5 cases of non epithelial malignancies and 30 cases of hemolymphoproliferative disease. Normal lymph nodes and non-epithelial lymph node metastases did not show any reaction to MAb b-12; on the contrary MCA positive staining was observed in 75 out of 75 (100%) lymph nodal metastases in breast cancer. These results suggest that application of MAb b-12 in immunohistochemistry is valid for the detection of bone marrow and lymph nodal micrometastases of epithelial origin.

Cross-reactivity between MUC1 antigen and MCA: false elevation of serum CA 15-3 level in pregnant and lactating women by Ma695-Ma552-based assay

PURPOSE

Cancer antigen 153 (CA 15-3) is one of the most commonly used biomarkers of breast cancer. However, elevated CA 15-3 is reported in pregnant and lactating women more frequently on Beckman DxI 800 immunoassay system (Ma695-Ma552 antibody pair) than on Abbott ARCHITECT system (115D8-DF3 antibody pair) in laboratory methodological evaluation. We conducted this study in order to figure out the reason behind this phenomenon.

METHODS

Serum CA 15-3 concentration was analyzed in 426 subjects, including 180 patients with breast cancer, 121 patients with benign breast disease, and 125 healthy volunteers (45 pregnant and 80 non-pregnant women). CA 15-3 assay was further validated using another cohort of 112 pregnant or postpartum women. Immunological cross reaction was analyzed by Western blotting and immunoprecipitation.

RESULTS

The serum CA 15-3 level was abnormally higher in almost 95% of the pregnant and lactating women detected using Ma695-Ma552 antibody pair (median: 71.4 U/mL) than that detected using 115D8-DF3 antibody pair (median: 16.5 U/mL). Western blotting and immunoprecipitation indicated that such a significant difference was mainly due to the cross reaction between monoclonal antibody Ma552 and mucin-like carcinoma-associated antigen (MCA).

CONCLUSIONS

The CA 15-3 assay using 115D8-DF3 antibody pair is more suitable for monitoring therapy in pregnancy-associated breast cancer.

Mucin-like carcinoma-associated antigen in paired serum and breast milk samples of lactating mothers and sera of their neonates in the early postpartum period

OBJECTIVE

To evaluate postpartum MCH changes in the early postpartum period, and to examine whether neonatal MCA is related to that in maternal serum (MS) or milk.

STUDY DESIGN

MCA was measured by EIA on the second and fifth postpartum day in serum and BM from 30 lactating women and their single term neonates. Sera from 20 healthy women (controls), were also analyzed.

RESULTS

All neonatal antigen concentrations were below the cut-off level for MCA (11 ng/ml). MS MCA was significantly increased compared with that in controls (P<0.00001), while antigen values in BM were highly elevated (P<0.00001), with a significant increase (P<0.0003) from the second to the fifth postpartum day. A strong correlation was found between the second and fifth day postpartum samples in MS, neonatal serum and BM MCA concentrations (r(s)=0.94, P<0.00001; r(s)=0.75, P<0.00001 and r(s)=0.69, P<0.0001, respectively). A significant correlation was also found in MCA values on the fifth postpartum day between neonatal serum and BM (r(s)=0.54, P<0.02).

CONCLUSIONS

From these findings one may speculate on some ripening process in milk production and a possible transition of MCA from the neonatal gastro-intestinal tract into circulation.

c-erbB-2 oncoprotein, CEA, and CA 15.3 in patients with breast cancer: prognostic value

The diagnostic value of a new tumor marker, c-erbB-2, was studied in the sera of 50 healthy subjects, 58 patients with benign breast diseases, and 413 patients with breast cancer (186 locoregional, 185 with advanced disease, and 42 with no evidence of disease). Using 15 U/ml as the cut-off, no healthy subjects or patients with benign diseases and only 2.4% of no evidence of disease patients had elevated serum levels. Abnormal c-erbB-2 levels were found in 29% (101/370) of the patients with breast carcinoma (locoregional 9%, metastases 45.4%). CEA (cut-off 5 U/ml) and CA 15.3 (cut-off 35 U/ml) sensitivity was 18% and 16% in patients with locoregional disease and 61% and 70% in those patients with advanced disease, respectively. A trend toward higher serum levels of all three tumor markers in patients with nodal involvement or greater tumor size was found, but was statistically significant only with CEA (p < 0.01). By contrast, c-erbB-2 was related to steroid receptors, in both locoregional and metastatic tumors. When the prognostic value of these markers was evaluated, patients with abnormally high presurgical CEA and c-erbB-2 had a worse prognosis than those patients with normal values, in both node-negative (p < 0.05 and p < 0.001, respectively) and node-positive patients (p < 0.556 and p < 0.001, respectively). By contrast, no relationship was found between CA 15.3 values and prognosis. Multivariate analysis showed that CEA and c-erbB-2 were also prognostic factors. The correlation between serum and tissue levels of c-erbB-2 was studied in the tumors of 161 patients. Significantly higher c-erbB-2 serum levels were found in patients with overexpression in tissue by immunohistochemistry, in both locoregional and advanced disease (p = 0.0001). Serum concentrations in patients with advanced disease were related to the site of recurrence, with significantly higher values in patients with metastases (mainly in those with liver metastases) than in those with locoregional recurrence. In summary, c-erbB-2 serum levels seem to be a useful tumor marker in the prognosis of patients with breast cancer. Using all three tumor markers, sensitivity was 35% in patients with locoregional breast cancer and 88% in patients with recurrence.

Mucin-like carcinoma associated antigen (MCA) at presentation with breast cancer

The usefulness of serum measurements of mucin-like carcinoma associated antigen (MCA) in 100 women at presentation with breast cancer was evaluated. Peripheral venous blood was drawn and MCA values determined by radioimmunoassay. Twenty women presenting with benign breast disease and 20 normal women served as controls. There was no difference in the MCA values between the benign breast disease group and the normal group: 4.1 +/- 0.9 units/ml versus 5.0 +/- 0.75 units/ml (mean +/- sem). The following were the MCA values for patients by stage; stage 1: 11.2 +/- 1.02, stage 2: 11.0 +/- 1.29, stage 3: 20.2 +/- 6.7, stage 4: 31 +/- 5.0. Statistical analysis of stage versus controls showed significant elevations only in stage 3 and 4 disease (p < 0.05). We conclude that MCA may be a useful serum tumour marker only in advanced breast cancer but is unreliable in detection of early breast cancer.

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.

Applications of immunogold and lectin-gold labeling in tumor research and diagnosis

Immunohistochemistry and carbohydrate histochemistry have had an enormous impact on both tumor research and diagnosis. In particular, immunogold labeling has provided significant advantages over classical fluorescence and enzyme-based techniques. In light microscopy, the silver-intensified gold labeling has proven highly sensitive and precise in localization. In electron microscopy, the gold particle marker was a prerequisite for successful and unequivocal antigen detection in electron-dense cellular structures such as secretory granules. In this review we demonstrate the usefulness of light and electron microscopical gold labeling techniques as applied in tumor research and diagnosis. The examples include expression of beta-1,6 branches and specific sialoglycoconjugates in colon carcinoma, b-12 carbohydrate epitope in breast carcinoma, polysialic acid in neuroendocrine tumors of lung, adrenal and thyroid, as well as studies on proinsulin to insulin conversion in insulinomas. In addition, practical hints for prevention of background staining, tissue fixation, and silver intensification of gold labeling are given.

Serum CA549 in primary breast cancer: comparison with CA15.3 and MCA

We carried out a comparison of three commonly used mucin markers, CA549, CA15.3 and MCA. Serum samples from 184 healthy women and 237 patients with primary breast cancer were evaluated. The markers were measured using commercially available immunometric assays. Like CA15.3 and MCA, CA549 was significantly associated with tumour size and lymph node status, being an effective indicator of tumour bulk. CA549 was significantly correlated with both CA15.3 and MCA. Positive/negative concordance rate was very good (93.7%) between CA549 and MCA. Conversely, CA15.3 was positive and CA549 negative in 20.4% of cases. Axillary status was not significantly different in the latter group of patients and in cases in which CA15.3 and CA549 showed concordant results. From the present findings we draw the following major conclusions: 1. CA549 and MCA are highly correlated and their association should not provide additional information; however, they should not be considered interchangeable since they may behave differently in individual cases. 2. CA549 and CA15.3, although well correlated, are discordant in a significant number of cases. Longitudinal studies are needed to verify the usefulness of the association between the two markers. 3. The three evaluated mucin markers are not interchangeable in individual patients; if a patient is monitored with a marker, she should be followed up with the same marker.

Simple method for comparing reliability of two serum tumour markers in breast carcinoma

AIMS

To compare the two breast tumour markers, CA15-3 and mucinous-like carcinoma associated antigen (MCA), using Receiver Operating Characteristic (ROC) curve analysis.

METHODS

One hundred and ninety six patients "presenting" with breast carcinoma had serum CA15-3 and MCA concentrations measured.

RESULTS

Using these markers as indicators of stage IV disease at the recommended laboratory level, true positive rates (TPR) and false positive rates (FPR) were obtained as follows: CA15-3 TPR = 75%, FPR = 7.4%, MCA TPR = 80%, FPR = 59.1%. By increasing the CA15-3 cutoff level to 45 U/ml, a TPR and FPR of 75% and 0.6%, respectively were obtained. By increasing the MCA cutoff level to 23 U/ml, a TPR and FPR of 65% and 2.3%, respectively, were obtained.

CONCLUSIONS

Using ROC curve analysis shows that CA15-3 is a superior indicator of metastatic breast disease than MCA at recommended laboratory levels, and by altering the cutoff points, the specificity and sensitivity for both these markers can be improved.

Rapid, Automated Enzyme Immunoassay for MCA with the Cobas® Core Roche Immunochemistry Analyser

The breast cancer marker Mucin-like Carcinoma-associated Antigen (MCA) was evaluated in a version that has been adapted to a new enzyme immunoanalyser, the CobasR Core. The two-step sandwich assay has a short total assay time of less than 60 minutes. Standard curves are stable for at least 2 weeks. The coefficients of variation for the inter-assay precision ranged between 3.6% and 7.8%, but were mainly below 5%. Single determinations of patient values from different runs correlated also very closely (R = 0.99). The dilution linearity for a set of 14 sera exhibited recovery rates mostly ranging from 90% to 110%. From 165 blood donors investigated, more than 99% had values below the cut-off of 11 U/ml. As demonstrated for pathological sera, the automated and manual versions showed a high degree of accordance (R = 0.98). The investigation presents convincing evidence that the Cobas Core MCA EI A running on a CobasR Core analyser guarantees a high analytical reliability and reproducibility.

The Diagnostic Value of Mucinous Carcinoma-Associated Antigen (MCA) Tests in Breast Carcinomas

MCA (Mucinous Carcinoma-Associated Antigen) levels of 176 breast carcinoma patients were tested postoperatively by serial determination. One hundred forty-one patients had nonprogressive disease (PD–) while 35 were in the progressive phase (PD +); in the latter the diagnosis was confirmed by means of current diagnostic procedures.

One hundred seventeen of the 141 PD– patients showed MCA levels below cutoff whereas 27 of the 35 PD + cases showed high values. The difference in the incidence of elevated MCA levels between PD–and PD + groups was statistically significant (p < 0.05). The overall diagnostic efficacy of MCA assays showed 77% sensitivity and 82% specificity.

A comparison of CA-549 with CA 15-3 and MCA in patients with metastatic breast cancer

CA 15-3, MCA, and CA-549 levels were determined in the serum of 56 patients with metastatic breast cancer, all of whom had visceral and/or bone metastases. CA 15-3 was positive in the serum of 37 patients, MCA in the serum of 38 patients, and CA-549 in the serum of 39 patients. All 3 markers were positive in 36 patients, and all 3 were negative in 16 patients. In the serum of 4 patients only 1 or 2 markers were slightly elevated. Thus, the results were identical in 52 of the 56 patients. It is concluded that CA 15-3, MCA, and CA-549 are sensitive markers for advanced breast cancer, and that no advantage can be expected by combining them.

Sensitivity and specificity of CA242 in gastro-intestinal cancer. A comparison with CEA, CA50 and CA 19-9

A serological assay for the quantitative determination of the novel tumour-associated epitope CA242 was developed and used for determination of sensitivity and specificity of CA242 in gastrointestinal cancer. The CA242 assay showed a better tumour specificity than CA50 (and CA 19-9). This was most noticeable in benign hepatobiliary disease. The sensitivity at 90% specificity cut-off level was approximately three times higher for CA242 compared to CA50 in colo-rectal cancer Dukes A, B and C, while in pancreatic cancer the sensitivity of CA242 and CA50 was similar. CA242 was expressed independently of CEA, and the combination of CEA and CA242 gave in colo-rectal cancer considerably higher sensitivity than the use of only one of the markers. This was most pronounced in Dukes A and Dukes B patients. CA242 is a novel tumour marker of potential clinical use, particularly in colo-rectal cancer.

Placental isoferritin (PLF) in comparison with MCA and CEA in advanced breast cancer--first data from a pilot study

The development of new and effective marker substances has optimized tumor-marker-guided follow-up programs to monitor generalization of disease and to assess the therapeutic outcome. Isoferritins of placental origin were first determined in the serum of patients with lymphoproliferative disease by way of the recently developed monoclonal antibody CMH-9. We have set up an Austro-Israeli working group and analysed 64 patients in terms of the sensitivity of placental ferritin (PLF) compared with the standard markers carcinoembryonic antigen (CEA) and mucinous-like cancer-associated antigen (MCA) in patients with metastatic breast cancer. We have additionally evaluated the importance of combined marker determination. Analysis of the data in view of site of metastatic spread yielded satisfying results both for PLF (sensitivity 70.4%) as well as MCA (sensitivity 76.9%) for visceral metastases; a combination of these two markers revealed a striking sensitivity of 88.4%, which, however, could not be improved by adding the third marker (CEA). With regard to non-visceral metastases, CEA and MCA were clearly superior.

The value of MCA, CA 15-3, CEA and CA-125 for discrimination between metastatic breast cancer and adenocarcinoma of other primary sites

MCA, CA 15-3, CEA and CA 125 were determined in the serum of 49 patients with metastatic breast cancer and 38 patients with metastatic adenocarcinoma of other primary sites. By using the 99th percentile of the normal value distribution as the cut-off point, the positive predictive value (PV+) was found to be 85% (95% CI 76-94) for MCA, and 71% (95% CI 61-81) for CA 15-3. When receiver-operating-characteristic (ROC) curves were constructed, the PV+ for CA 15-3 was increased to 82% (95% CI 72-92), using 60 U ml-1 as the cut-off point. With the exception of two patients who had a slightly elevated MCA, MCA and CA 15-3 identified the same patients with breast cancer. By combining a positive MCA or CA 15-3 with a negative CEA and CA 125, further improvement of the PV+ could be achieved; 100% (95% CI 91-100). We conclude that MCA and CA 15-3 may play a useful role in discrimination between patients with metastatic breast cancer and those with adenocarcinoma of other primary sites.

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.

Serological screening for a mucine-like carcinoma-associated antigen (MCA) in patients with gastrointestinal tract malignancies

Mouse monoclonal antibody b-12 identifies a high-molecular-mass glycoprotein antigen strongly expressed by breast carcinoma cells. Since immunohistochemical studies have also demonstrated some reactivity with other epithelial neoplasms, and since "mucine-like carcinoma-associated antigen" (MCA) has gained considerable interest as a tumor marker in breast cancer, we have investigated 34 patients with histologically proven advanced gastrointestinal malignancies for the presence of elevated MCA serum levels. Our data suggest that screening for and/or monitoring of MCA in these tumors is unlikely to have any practical clinical relevance. The possible role of MCA as a marker in tissue specimens for abortive adenomatous differentiation in gastrointestinal (and other) neoplasms, however, remains to be determined.

Mucin-like cancer-associated antigen (MCA) compared with CA 15-3 in advanced breast cancer

Mucin-like cancer-associated antigen (MCA), a new tumor marker using the mouse monoclonal antibody b-12 is thought to be of value in the management of patients with breast cancer. In this study sera from 191 female patients with breast cancer (112 with progressive disease [PD] and 79 with no evidence of disease [NED]) were analyzed for MCA levels and compared with those of cancer antigen 15-3 (CA 15-3) in single determination and in combination with carcinoembryonic antigen (CEA) and tissue polypeptide antigen (TPA). A cut-off level of 14 U/ml for MCA seems to be more appropriate than the recommended 11 U/ml to distinguish between PD and NED in patients with breast cancer. Although there was a fairly good correlation of MCA to CA 15-3, MCA was inferior in sensitivity and specificity to CA 15-3. Patients with osseous metastases and those with more than one metastatic site showed higher MCA levels than patients with visceral or soft tissue metastases, a fact which was comparable to CA 15-3. Combining MCA and CA 15-3 resulted in a gain in specificity but marked loss of sensitivity. The combination of MCA and CEA results also in a loss of sensitivity whereas the combination of CA 15-3 and CEA showed an increased specificity and only a negligible loss of sensitivity. The combination of MCA with TPA is of little value in the follow-up of breast cancer, as is the combination of CA 15-3 with TPA. The combination of CA 15-3 with CEA can be still recommended for follow-up for early detection of metastases in breast cancer.(ABSTRACT TRUNCATED AT 250 WORDS)

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.

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.

A mucinous-like carcinoma-associated antigen (MCA) in the tissue and blood of patients with primary breast cancer

The monoclonal antibody (MAb) b12 raised against human breast cancer cell lines was found to identify an epitope of a mucinous-like carcinoma associated antigen (MCA) that is strongly represented on breast tumor cells. The b12 MAb was used to develop an enzyme immunoassay (EIA) kit. MCA levels were measured with the EIA method in the cytosol of both breast cancer and normal breast tissue as well as in the blood of 147 patients with primary breast cancer and 92 healthy subjects. MCA cytosol levels were significantly higher in carcinoma than in normal breast tissue cytosol samples. Higher MCA levels were found in the cytosol of tumor without lymph nodal involvement. The 95th percentile of the MCA value distribution in the healthy control group (11.0 U/ml) was chosen as negative/positive cut-off level. The overall positivity rate in breast cancer group was 26.5% with MCA showing a trend toward higher levels in patients with more advanced disease. Significantly higher levels were found in patients with a higher number of positive lymph nodes.

Primary duodenal carcinoma arising in a non-vaterian tubulo-villous adenoma. A case report with immunocytochemical analysis and review of the literature

Primary duodenal carcinoma and duodenal adenoma are rare tumours. Duodenal carcinoma makes up about 0.3% of all malignant tumours of the gastrointestinal tract (Alwmark et al. 1980; Spira et al. 1977). The present paper describes a duodenal carcinoma arising in a mixed tubulo-villous non-Vaterian adenoma in a 68 year old male. Immunocytochemical analysis revealed evidence of neuroendocrine differentiation in both adenoma and carcinoma. In a review of the literature a correlation between the size of adenoma and the probability of concomitant carcinoma is demonstrated. Duodenal adenoma measuring more than 4 cm in diameter should be considered potentially malignant.

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.

The immunohistochemical reactivity of a new anti-epithelial monoclonal antibody (MAb b-12) against breast carcinoma and other normal and neoplastic human tissues

A mouse monoclonal antibody, MAb b-12, has been described previously (Stähli et al. 1985) which reacts with a Mr 350 kD glycoprotein with mucin-like characteristics (Stähli et al. 1987) expressed in cytoplasm and on the surface of human breast carcinoma cell lines (MCF-7 and ZR-75-1). In the present report the immunohistochemical reactivity of this MAb with normal and malignant human tissues is analyzed. Pre-experiments showed that the epitope b-12 is resistant to formalin treatment allowing the use of tissue processed by standard paraffin embedding methods. 167 normal and 408 neoplastic tissues were tested by indirect immunofluorescence or the avidin-biotin complex method. MAb b-12 stained the apical cytoplasm of secretory epithelia and their secretions including the acinar and ductular epithelia of the breast. It reacted with all breast carcinomas independent of their histological type or stage, frequently with all but in some cases with a fraction of the tumour cells. Some other carcinomas, primarily those of adenomatous differentiation, were also reactive. In these, however, the fraction of positive tumour cells was usually lower. The b-12 epitope is thus a marker for normal and neoplastic epithelia with secretory functions, particularly for breast carcinomas of all histological types and stages, and perhaps a differentiation marker for abortive adenomatous differentiation in solid carcinomas of the gastro-intestinal, uro-genital or respiratory tract.