Analytical and clinical evaluation of a new tumor marker in breast cancer: CA 27.29

Evaluation of a radioimmunoassay for a new tumor marker, named CA 27.29, recently proposed for use in breast cancer patients, is reported in this study. After considering the analytical performance, the clinical study was directed to a control group of 66 apparently healthy subjects (Controls), a group of 25 women with benign breast disease (BBD) and a group of 164 breast cancer patients divided into primary before any treatment (M-), in follow-up with no evidence of disease (NED) and presence of metastases (M+). When compared to CA 15.3, our results showed similar sensitivity of both markers with a slightly lower specificity for CA 27.29. In some cases, however, CA 27.29 elevation appears earlier than CA 15.3 as a sign of metastases. We thus propose their associated use.

Relationship between Cytosol Tps, Tpa and Cell Proliferation

The serological tumor marker tissue polypeptide antigen (TPA) and the more recently identified tissue-specific polypeptide antigen (TPS) have been reported to be indicators of the proliferation rate of the tumor. In the present investigation we compared the cytosol level of the two markers with the proliferative activity of the tumor measured using the 3H-thymidine labelling index. The preliminary results presented here show that higher TLI is associated with lower cytosol levels of both TPA and TPS. TPA and TPS in the cytosol were significantly associated. These findings are in agreement with the previously demonstrated association between high TPA cytosol levels and better prognosis in breast cancer. Further studies are ongoing in order to:

1. confirm these findings in a larger patient series;

2. investigate any possible prognostic indication provided by TPS;

3. evaluate any possible biological meaning of the negative association between TPA/ TPS and TLI in the cytosol of breast cancer.

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.

Methods

In 289 breast cancer patients submitted to an intensive post-operative follow-up with tumour markers, we compared MCA (cut-off values, ≥ 11 and ≥ 15 U/mL) with CEA or CA15.3 or TPA for detection of relapse. In addition, we compared the MCA-CA15.3 and CEA-TPA-CA15.3 tumour marker panels.

Results

Distant metastases occurred 19 times in 18 (6.7%) of the 268 patients who were disease-free at the beginning of the study. MCA sensitivity with both cut-off values was higher than that of CEA or TPA or CA15.3 (68% vs 10%, 26%, 32% and 53% vs 16%, 42%, 32% respectively). With cut-off ≥ 11 U/mL, MCA showed the lowest specificity (42%); with cut-off ≥ 15 U/mL, MCA specificity was similar to TPA (73% vs 72%) and lower than that of CEA and CA15.3 (96% and 97% respectively). With ≥ 15 U/mL MCA cut-off, MCA sensitivity increased from 53% to 58% after its association with CA15.3. Sensitivity of CEA-TPA-CA15.3 panel was 74% (14 of 19 recurrences). Eight of the 14 recurrences early detected with CEA-TPA-CA15.3 presented as a single lesion (oligometastatic disease) (5) or were confined to bony skeleton (3) (26% and 16% respectively of the 19 relapses). With ≥ 11 U/mL MCA cut-off, MCA-CA15.3 association showed higher sensitivity but lower specificity, accuracy and positive predictive value than the CEA-TPA-CA15.3 panel.

Conclusion

At both the evaluated cut-off values serum MCA sensitivity is higher than that of CEA, TPA or CA15.3 but its specificity is similar to or lower than that of TPA. Overall, CEA-TPA-CA15.3 panel is more accurate than MCA-CA15.3 association and can "early" detect a few relapsed patients with limited metastatic disease and more favourable prognosis. These findings further support the need for prospective randomised clinical trial to assess whether an intensive post-operative follow-up with an appropriate use of serum tumour markers can significantly improve clinical outcome of early detected relapsing patients.

Comparison of tissue polypeptide antigen (TPA) with cancer antigen 15-3 (CA 15-3) and carcinoembryonic antigen (CEA) in follow-up of breast cancer

Cancer antigen 15-3 (CA 15-3), carcinoembryonic antigen (CEA) and tissue polypeptide antigen (TPA) were measured in 679 sera of breast cancer patients and in 94 sera of women without breast cancer. The tumour markers were determined using immunoluminometric assays (ILMA). The assays are characterised by an inter-assay-imprecision and intra-assay-imprecision <4 %. The breast cancer patients were staged according to the TNM classification stage 0-IV (by UICC) in patient groups with a compatible prognosis. Median and range of each stage were investigated. The cut-off values (95th and 97.5th percentile of control group) of CA 15-3, CEA and TPA were determined; specificity, sensitivity, positive and negative predictive value (PV) and efficiency were investigated for these cut-off's and the receiver operating characteristic (ROC) curves were calculated. The differences between control group and stage 0-3 were shown as non-significant for CA 15-3 and CEA but significant for TPA. Significant differences were found in stage 4 for all three tumour markers. The three tumour markers did not have differences in specificity, positive and negative PV and efficiency. TPA and CA 15-3 demonstrated comparable results in sensitivity and ROC curve analyses. These results were better than those from CEA.

Differential responsiveness of proliferation and cytokeratin release to stripped serum and oestrogen in the human breast cancer cell line, MCF-7

In vitro research into hormone sensitivity and the relation to proliferation of cytokeratin release from cancer cells is scarce. Therefore, we examined the stimulation of proliferation and the release of cytokeratins in a breast cancer cell culture model. Cell growth was stimulated by 17 beta-oestradiol (10(-11) M), stripped serum (10%) and by the two together. Cytokeratin release was stimulated only by stripped serum, oestradiol having no effect. After long incubation periods (> 12 h), cytokeratin release also commenced in the control and oestradiol treatments. Release rate versus time analysis suggested that there are two different release processes. Cytokeratin release was first stimulated at a stripped serum concentration approximately 100 times lower than that which initiated proliferation. Pharmacological alteration of proliferation with cordyceptin resulted in growth changes without alterations in cytokeratin release. We conclude that cytokeratin release in these cells is unrelated to proliferation, independent of oestrogen action and probably in some way related to growth factor receptor function.

Serum tumor marker kinetics and the clinical course of patients with advanced breast cancer

Serum carcinoembryonic antigens (CEA), CA 15-3, and tissue polypeptide antigens (TPA) have been used in monitoring the clinical course of patients with breast cancer. However, recent reports have suggested that the serial levels of these markers during therapy do not always correlate with the response to therapy. To clarify the usefulness of the serial combination assay of these markers in monitoring the clinical course of patients during therapy, we investigated the relationship between the initial changes and the kinetic patterns of the markers after therapy and the objective responses. When an increase or decrease of over 20% in these markers is taken to be significant, then the initial changes in all three markers significantly correlated with the therapeutic responses (P < 0.01). Five distinct kinetic patterns in the marker levels were observed. A paradoxical kinetic pattern of CEA and CA 15-3 levels--that is, an "initial surge and subsequent drop"--was seen in one-third of the responders. The TPA levels tended to exhibit a "steady decline" pattern in those responders. The sensitivity and specificity of the kinetic patterns to predict the clinical courses were significantly higher than those obtained from the analysis of initial changes. These findings thus suggest that adequate knowledge of the unique kinetics of each marker may help to make a more accurate prediction of the therapeutic responses.

Tissue Polypeptide Antigen Immunostaining in Fine Needle Aspirates from Solid Breast Nodules

the purpose of this study was to determine the role of Tissue Polypeptide Antigen (TPA) immunostaining in the evaluation of aspiration smears from solid breast nodules and to discuss its possible clinical applications. Seventy-one cytologic specimens were studied; 52 were carcinomas, 15 fibroadenomas and 4 fibrocystic dysplasia. TPA was visualized with the peroxidaseantiperoxidase method, using 3-3 ‘diaminobenzidine as chromogen and hematoxylin as counterstaining. The incidence of TPA-positive aspiration smears was 88.5% in the carcinomas and 26.7% in the fibroadenomas. The four cases of fibrocystic dysplasia showed variable behaviour. The intensity of the TPA staining varied from – to + + + and was most frequently high in the carcinomas. The results of this research show a good correlation between a diagnosis of carcinoma and TPA positivity in fine needle aspirates of solid breast nodules.

Tissue polypeptide antigen in breast cancer cytosol: a new effective prognostic indicator

Since 1982 we have been evaluating oestrogen and progesterone receptors (PgR), cathepsin D and the cytosolic levels of the tumour marker, tissue polypeptide antigen (TPA), in 257 patients radically resected for breast cancer (follow-up 24-81 months). TPA was measured by an immunoradiometric assay previously validated for cytosol. No significant associations were found between cytosolic TPA and age, tumour size, lymph-node status, receptor status and cathepsin D. TPA+ cases showed a significantly longer disease-free survival (DFS) and overall survival (OS) than TPA-patients (log-rank P < 0.0001). The prognostic value of cytosolic TPA was also demonstrated after stratification by nodal status, PgR and cathepsin D. The prognostic value of TPA was independent of the other prognostic indicators, being the most powerful among the evaluated indices (Cox multivariate analysis: chi 2 15.5 for DFS, 11.4 for OS). We conclude that cytosolic TPA is a powerful additional prognostic factor in primary breast cancer. Its prognostic role should therefore be extensively evaluated.