A prospective study of tissue polypeptide specific antigen (TPS) in breast cancer diagnosis.

The aim of the present study was to evaluate the clinical value of a new tumour marker TPS in sera from patients with breast cancer and patients with benign breast disease. The results for TPS were compared with those for TAG 12, CA 15-3 and MCA. The cutoff levels (90% specificity) determined for each test were 108.0 U/1 for TPS, 57.5 KU/1 for TAG 12, 24.8 KU/1 for CA 15-3 and 9.7 KU/1 for MCA. The diagnostic sensitivity of the TPS test was 0.21, for the TAG 12 test it was 0.2, 0.13 for the CA 15-3 test and 0.12 for the MCA test in detecting breast cancer. TPS, TAG 12, CA 15-3 and MCA tests were tested in a multivariate analysis to find the best combination of independent predictors of breast cancer. The most important predictor of breast cancer was TAG 12 followed by TPS. In order to calculate the contributions of tumour marker tests, a diagnostic score (DS) was developed. The diagnostic score (DS) was: DS = TPS x 0.0085 x TAG 12 x 0.0596 - CA 15-3 x 0.0866 - MCA x 0.2938 + 0.1738. The sensitivity of the DS in detecting breast cancer was 55% with a specificity of 90% and an efficiency of 64%. In conclusion, new tumour markers TPS and TAG 12 may have some value in breast cancer diagnosis. In particular, the results indicate the usefulness of computer assistance and a simple diagnostic score when tumour markers are used in breast cancer diagnosis.