The Role of TPS and TPA in the Diagnostics of Distant Metastases

Abstract

Aim: The aim of the study was to assess the degree to which tissue polypeptide antigen (TPA) and tissue polypeptide-specific antigen (TPS), as well as carcinoembryonic antigen (CEA), can assist in the detection of distant metastases.

Patients and methods: We assessed 157 patients with colorectal and breast cancer divided into two groups. The first was a group of patients with cancer at stages 1, 2 and 3; the second was a group of patients with cancer at stage 4 with metastasis.

Results: We found significantly higher levels of all biomarkers in the metastatic group compared to the group with cancer at stages 1-3 (p<0.0001). The calculated area under the receiver operating characteristic (ROC) curve was 0.9929 for TPS, 0.9337 for TPA and 0.7234 for CEA. The cut-off was calculated for each biomarker at 95% specificity, TPS cut-off=255 IU/l (sensitivity 95%), TPA cut-off=200 IU/l (sensitivity 70%) and CEA cut-off=18 μg/l (sensitivity 37%).

Conclusion: We suggest combining CEA with TPS or TPA in the detection of distant metastases or using only cytokeratins. This approach can significantly increase the quality of detection of the metastatic process.

Keywords: CEA; Colorectal cancer; TPA; TPS; breast cancer; distant metastasis.