Detection of circulating tumour cells in patients with stage I-III breast cancer

Aim. To increase the accuracy of risk stratification of breast cancer Stage I-III patients based on circulating tumour cell (CTC) determination. Methods. Forty-seven breast cancer patients aged 28-77 years (median, 51 years) who were examined and treated at N.N. Blokhin National Medical Research Center of Oncology between 2015 and 2017 were enrolled in the study. The presence of CTCs was evaluated for all patients before treatment. Results. CTCs were detected in 85.1% (40 out of 47) of the patients. The CTC detection rate in patients with early and locally-advanced breast cancer was approximately the same, 88.5% (23 of 26) and 81% (17 of 21), respectively (p = 0.7). Another important prognostic factor, which tended to be reliably linked to the frequency of CTC detection, was the grade of malignancy. Grade 2 tumours were more often observed in CTC-positive patients (77.5%) than in CTC-negative patients (22.5%, p = 0.06). None of the remaining clinical and morphological parameters were statistically associated with CTC positivity. Conclusion. This study demonstrated that regardless of the clinical stage, CTCs were detected with approximately equal frequency in patients with early and locally-advanced breast cancer (88.5% and 81%, respectively). However, owing to the small number of patients studied, none of the differences were found to be statistically significant. Nevertheless, investigations on the relationship between the presence of CTCs, molecular-biological subtypes and grade of malignancy are important to evaluate their use as independent prognostic factors. Further studies are needed to assess the use of CTCs as an additional criterion or prognostic factor in breast cancer management.