Dynamics of circulating tumor cells during neoadjuvant chemotherapy in patients with locally-advanced breast cancer

Abstract

Abstract Relevance. Circulating tumor cells (CTC) are a biological marker of new generation, which provides additional information on the biological features and prognosis of the disease. The possibility of using CTC for early evaluation of the effectiveness of drug treatment of breast cancer (BC), including neoadjuvant chemotherapy, is an important but insufficiently studied issue. Goal - to study the dynamics of CTCs in the process of preoperative chemotherapy in patients with locally-advanced BC. Materials and methods. Between 2015 and 2016 59 women over the age of 18 with verified BC and signed informed consent were included in the study. Patients with stage II and III were included. CTCs were evaluated in the blood before the start of treatment, after 2 courses of chemotherapy and before surgical treatment. To detect CTCs we used the ISET (Isolation by Size of Tumor cells) technique, based on vacuum cell filtration through a membrane with a given pore size of 8 mcm. Results. In 22 (37%) women CTCs were detected before treatment, including 6 (10%) patients with CTCs found on every stage of treatment. Among 37 (63%) patients without baseline CTCs 19 (32%) developed them in the process of chemotherapy. Baseline CTCs correlated with tumor size more than 25 mm and stage III disease. Also a tendency to increased CTC prevalence in patients with poor pathological response to chemotherapy was revealed. Conclusions. CTCs represent a novel biomarker. Yet, methodology needs to be standardized and more structured studies are badly needed to reveal their true biological relevance.

Keywords

• рак молочной железы
• неоадъювантное лекарственное лечение
• циркулирующие опухолевые клетки
• изоляция клеток по размеру