The efficacy of serum tumor markers CA15–3, CEA and hematological parameters in the prognosis of breast cancer in Iraqi women

Background. Cancer antigen 15-3 (CA 15-3) is commonly used as a tumor marker in breast cancer (BC), but its levels are not always elevated. This study assessed CA 15-3 and carcinoembryonic antigen (CEA) levels in BC patients at diagnosis and during follow-up. Aims. To evaluate the prognostic value of combining serum CA 15-3 and CEA levels with hematological parameters in breast cancer, and to assess their effectiveness in monitoring patients before and after surgery. Methodology. A cohort study was conducted on 38 Iraqi women (aged 18–70 years) diagnosed with stage I–III invasive ductal carcinoma. Age at menarche ranged from 9 to 17 years. Serum levels of CA 15-3, CEA, and vitamin D were measured using the ELISA method, while total serum calcium was determined using the QuantiChrom assay. All measurements were taken before surgery and one month post-surgery. Results. CA 15-3 and CEA levels showed significant reductions after surgery. Their combined use improved sensitivity and specificity, enhancing prognosis and monitoring. Serum vitamin D levels significantly decreased after surgery, while calcium levels showed a non-significant decline. Conclusions. The combination of serum CA 15-3 and CEA can serve as an effective prognostic marker in invasive breast cancer. Using a single tumor marker shows limited sensitivity and may not meet clinical diagnostic needs. Therefore, a combination of tumor markers is recommended to reduce the risk of misdiagnosis. Vitamin D deficiency is common in breast cancer patients and may contribute to disease progression, indicating its potential role as a prognostic marker.