An Innovative Approach to CTCs’ Liquid Surgery

Circulating Tumor Cells (CTCs) can be defined as cancerous cells which detached from the primary tumor and passed into the vascular or lymphatic systems. The blood flow can carry the cell in another region of the human body where it can extravasate and become the starting point for the subsequent growth of additional tumors (metastases) in distant organs.

This phenomenon causes a difficult tumor treatment, that can be more complicated because of the higher number of cancerous sites present at the same time. This mechanism is responsible for the vast majority of cancer-related deaths.

Because of this behavior, in the CTCs study it is paramount to acquire new data and knowledge to understand the mechanisms that leads to the separation of the cell from the tumor as well as the major characteristics of the specific category of cells. The better understanding of the CTCs behavior can lead to develop systems that can block and extract them during the blood flow before they can find a place to take root.

In this paper, two different strategies for blocking and extracting CTCs from the blood flow are investigated on the basis of specific characteristics of the CTCs. Some of the already proposed procedure to the extraction and evaluation of CTCs that are used to study the cells, outside the human body, are described as a starting background of the technologies proposed. Then, the liquid surgery new concept is described as the possibility to perform the "surgery" of the liquid phase of a solid tumor.

The aim of this research project is the development of an innovative therapeutic and diagnostic approach, or a medical device capable of removing CTCs from the peripheral blood of a cancer patient, during a conventional extracorporeal circulation procedure, identical to that used, for example, for renal failure.

In this work, some categories of CTCs are modeled to be used in computational fluid dynamics simulations from the point of view of the dimensions (radius, diameter, shapes) and the physiological and biochemical characteristics (ions concentration, surface charge, magnetic and electric indexes).

The first studies have been carried out on simple geometries to verify the behavior of cells and blood flowing in particular magnetic and electric fields conditions. These data are the baseline information to develop more complicated geometries and prototypes in which the flow can be subjected to different field intensity, velocity and obstacles.

Finally, preliminary results and behavior of the prototypes are presented with some specific parameters that can be interpreted as the removal efficiency (i.e. block factor). Some future developments are described to define subsequent research paths, some of which have already been implemented.