Purpose: Breast cancer is the most common neoplasm in women and has the highest associated mortality rate. Rapid detection programmes can provide early diagnosis and increase the chances of survival. There are no specific tumor biomarkers for the early phase of the disease. The primary aim of this study was to search a blood biomarker with levels that exceeded the normal range established in the general population that could be used to screen breast cancer.
Methods/patients: Case-control study. Conventional as well as research (NGAL, EGFR and 8-OHdG) tumor biomarkers were analyzed.
Results: A total of 126 women were enrolled (cases: 63 patients with local breast cancer; Controls: 63 healthy women). Significant differences were found in patients with higher levels of the conventional markers, Ca15.3, CEA, Cyfra 21.1 and NSE. However, when commercial cut-off values were used, only Ca 15.13 was significant. In the group of research biomarkers, significantly higher levels of EGFR were found in the control group, and of 8-OHdG in the case group. Using logistic regression analysis and a ROC curve, an equation composed of five markers, Ca 15.3, NSE, NGAL, EGFR and 8-OHdG, which yielded a correct diagnostic probability of breast cancer of 91.8% was obtained.
Conclusions: 8-OHdG has been identified as a new potential marker for screening early stage breast cancer. In addition, a model that combines five blood markers that can be used as a diagnostic test in certain groups of patients has been developed. New studies with a larger sample size are needed to verify the results obtained.
Keywords: Breast cancer; Early diagnosis; Oxidative stress; Serum tumor biomarkers.