Serum tumour markers as a diagnostic and prognostic tool in Libyan breast cancer

Results from studies on efficacy of carcinoembryonic antigen (CEA), carbohydrate antigen 15.3 (CA 15.3) and thymidine kinase (TK1) as diagnostic and prognostic tools for primary breast cancer (BC) have presented conflicting results, and usefulness of these markers for clinical use in BC remains unclear. The aim of this study is to evaluate potential of concentration of the sera CEA, CA15.3 and TK1 peptides' use as markers in the diagnosis and prognosis of breast lesions of Libyan patients. Serum tumour markers were studied in 20 healthy subjects, 30 patient with benign lesion diseases and 50 patients with histologically confirmed BC diagnosed at the National Cancer Institute (NCI), Misurata, Libya during the period 2005-2009. The concentrations of the BC patients' cutoff points used for diagnostic and prognostic sensitivity were 8.82 ng/ml, 35.57 U/ml and 32.57 U/mg/protein for CEA, CA15.3 and TK1, respectively. Increased CEA (>8.82 ng/ml), CA 15.3 (>35.57 U/ml) and TK1 (>32.57 U/mg/protein) concentrations were found in 62 %, 70 % and 78 % of the BC patients, respectively. For all three tumour markers, increased concentrations correlated increased tumour size and nodal involvement. Significantly higher serum TK1 levels were found in patients with advanced disease (p < 0.0001) and TK1 levels also correlated with disease-specific survival (DSS, p < 0.07). The combined data set of the three markers' data from three markers increased the diagnostic sensitivity to 90 %. The serum marker analysis for CEA, CA 15.3, and S-TK1 concentrations is shown to be a useful tool for identification of malignant cases in our BC population and for the prognostic evaluation of patients with primary BC. Increased concentrations of the markers were also observed to be higher in patients with advanced tumours and indicative of the development of distant metastasis.