CEA Determination in the Follow-Up of Extracolorectal Neoplasms

Fluorescence quenching-based signal amplification on immunochromatography test strips for dual-mode sensing of two biomarkers of breast cancer

Recently, immunochromatography test strips (ICTS) have been fully developed for point-of-care testing (POCT). However, the intrinsic limitations including non-quantitative detection of colloidal gold ICTS and low sensitivity of fluorescence ICTS (FICTS) significantly restrict their further application in clinical diagnosis. Taking advantages of rapid colorimetric qualitative detection and fluorescence quantitation, we designed a kind of sensitive and dual-mode magnetic FICTS (mFICTS) based on PLGA@Fe3O4 super-paramagnetic nanosphere (SPMN) probes quenching multiplex fluorescer on the test line through sandwich immunoreactions. Owing to the large number of Fe₃O₄ nanoparticles (about 47) encapsulated in one SPMN, about 2680 Cy5 molecules were quenched by one SPMN on the test line such that to significantly improve the analytical sensitivity as well as the detection of whole blood samples via magnetic separation. Moreover, the aggregation of black SPMN on the test line enabled a quick naked-eye screening in 3 min. For high accuracy breast cancer diagnosis, combined determination of carcinoembryonic antigen (CEA) and carbohydrate antigen (CA153) was performed on one mFICTS with the limits of detection of about 0.06 ng mL^-1 and 0.09 U mL^-1, respectively. Then, more than 50 clinical serum samples were investigated for high-resolution screening by mFICTS, and the results were coincident with those obtained by electrochemiluminescence immunoassay (ECLIA). Thus, the designed mFICTS is suitable for point-of-care diagnostics.

Diagnostic efficacy of CA 15-3 and CEA in the early detection of metastatic breast cancer-A retrospective analysis of kinetics on 743 breast cancer patients

OBJECTIVE

We investigated the diagnostic capacity of CEA and CA 15-3 kinetics for the early detection of metastatic disease in comparison to fixed cut off values.

METHODS

In a retrospective analysis, a total of 743 patients with early breast cancer and available baseline values of CEA and CA 15-3 were included. A reproducible increase of 100% of single or combined markers was considered as a strong indicator of metastatic disease.

RESULTS

187 patients developed metastatic disease and 556 remained disease-free. On the basis of tumor marker kinetics, we reached a specificity of >98% for both biomarkers and a sensitivity of 40.6% for CEA alone, 55.6% for CA 15-3 alone and 66.3% for the combination of both markers. Using fixed cut-off values (CEA: 4ng/mL, CA 15-3: 30U/mL) we ended up with a specificity of 86.3% and a sensitivity of 70.6% for the combination of CEA and CA 15-3. Using higher cut-off values (CEA: 6ng/mL, CA 15-3: 60U/mL) we reached a specificity of 96.9% and a sensitivity of 49.7% for the combination.

CONCLUSION

We conclude that the interpretation of these markers in follow-up using individual baseline values and kinetics leads to a significant superior profile of specificity and sensitivity.

Assessing benefits of combining biochemical and immunological markers in patients with lung carcinoma

Establishment of a simple biochemical index for diagnosis of cancer and management of patients with neoplastic diseases remains one of the important goals to be achieved in cancer research. The current investigation determined serum levels of carcinoembryonic antigen (CEA), total sialic acid (TSA) and lipid bound sialic acid (LSA) in 192 untreated lung cancer patients and compared with 80 age- and sex-matched controls (44 non-smokers and 36 smokers). The levels of all the markers were significantly elevated (P < 0.001) in lung cancer patients compared to the controls. CEA and LSA values were significantly raised (P < 0.001 and P < 0.01, respectively) in smokers compared to non-smokers. TSA and LSA values were more sensitive than CEA for diagnosis of lung cancer. Mean values of the three markers were higher in non-responders (n = 5) compared to the responders (n = 10). The results suggest that along with CEA, TSA and LSA might be included as routine parameters in lung cancer patients.