Background: The burden of breast cancer has grown rapidly in China during recent decades. However, the association between tumor markers (CA15-3, CA125, and CEA) and breast cancer survival among certain molecular subtypes is unclear; we described this association in a large, population-based study.
Methods: We conducted a cohort study including 10,836 women according to the Tianjin Breast Cancer Cases Cohort. Demographic and epidemiologic data were collected by a structured face-to-face questionnaire. Clinico-pathological parameters were abstracted from medical records, and follow-up information was obtained once a year by telephone. The primary endpoints were breast cancer-specific survival (BCSS) and disease-free survival (DFS). We utilized the Cox proportional hazard model to calculate hazard ratios (HRs) and 95% confidence intervals (CI).
Results: Among all patients, elevated CA15-3 and CEA exhibited consistently and statistically significant reduced BCSS compared with normal ones (CA15-3: HR 1.54, 95% CI 1.01-2.34; CEA: HR 2.45, 95% CI 1.40-4.30). Similar patterns of association were observed for DFS (CA15-3: HR 2.09, 95% CI 1.44-3.02; CEA: HR 2.71, 95% CI 1.71-4.27). Moreover, in luminal A subtype, high CA15-3 and CEA levels were associated with decreased BCSS (CA15-3: HR 4.47, 95% CI 2.04-9.81; CEA: HR 3.79, 95% CI 1.68-8.55) and DFS (CA15-3: HR 4.06, 95% CI 2.29-7.18, CEA: HR 3.41, 95% CI 1.75-6.64). In basal-like subtype, elevated CEA conferred reduction for BCSS (HR 5.13, 95% CI 1.65-15.9). However, no association was observed between CA125 and breast cancer outcome.
Conclusions: Preoperative CA15-3 and CEA levels differ in breast cancer molecular subtypes and yield strong prognostic information in Chinese women with breast cancer. Measuring CA15-3 and CEA levels before surgery may have the potential in predicting breast cancer survival and offering patients' personalized treatment strategy among luminal A and basal-like subtypes.
Keywords: Breast cancer; Molecular subtype; Survival; TBCCC; Tumor marker.