[Detection of circulating tumor cells in women with early breast cancer].

Background: There are multiple methods and biomarkers with different detection rates to circulating tumor cells (CTCs) in women with breast cancer (BC). However, to the best our knowledge, no study has been carried out to detect CTCs in women with early BC in Mexico. Objective: Calculate the detection rate of CTCs in peripheral blood of Mexican women with early BC by quantification of the relative expression of KRT19, MUC1 and SCGB2A2. Material and methods: Observational, longitudinal, analytical study, which included 62 Mexican women, over 18 years of age, with BC clinical stage 0, I and II. Cells with a density < 1.077 g/ml were isolated from 4 mL of peripheral blood obtained 24 h before surgery, RNAS was extracted and RT-qPCR was performed to quantify the relative expression of KRT19, MUC1 and SCGB2A2. Results: The diagnosis of BC was confirmed in the definitive pathological study in 59 women. 1 case (1.7%), expressed KRT19, 18 cases (30.5%) MUC1, 2 cases (3.4%) SCGB2A2, and 19 cases (32.2%) expressed at least one of the three biomarkers. Conclusions: CTCs detection rates were like those reported in other populations when MUC1 was used, but lower when KRT19 and SCGB2A2 were used. Standardization of blood sample collection and processing, as well as biomarker expression analysis, is important to reduce variability in the detection of CTCs in specific populations.