The ISET Test (Isolation by SizE of Tumor cells / Trophoblastic cells) is a diagnostic blood test that detects

circulating tumor cell A circulating tumor cell (CTC) is a cell that has shed into the vasculature or lymphatics from a primary tumor and is carried around the body in the blood circulation. CTCs can extravasate and become ''seeds'' for the subsequent growth of additional ...

s in a blood sample. The test uses an in-vitro diagnostic system developed at INSERM, the

Université Paris Descartes Paris Descartes University (french: Université Paris 5 René Descartes, links=no), also known as Paris V, was a French public university located in Paris. It was one of the inheritors of the historic University of Paris, which was split into 13 ...

and Assistance Publique Hôpitaux de Paris (AP-HP) in order to isolate cancer cells from blood without loss and identify them through a diagnostic cytopathology-based approach. __TOC__

Operation

A 1- ml sample of blood will typically contain 5 to 10 million leukocytes, 5 billion erythrocytes, and a small number of circulating rare cells, including: * non-tumor cells such as epithelial-normal cells, epithelial-atypical cells, endothelial vells and stem cells; * physiological state-dependent cells such as fetal cells in pregnant and ex-pregnant women; *

s (CTCs) which are of diagnostic value in diagnosing various cancers. The diagnostic problem is to find and identify the rare CTCs among the abundant other cells in a given blood sample. The ISET technology is based on the observation that tumor cells of all types of solid cancers are larger than blood cells (

leukocyte White blood cells, also called leukocytes or leucocytes, are the cells of the immune system that are involved in protecting the body against both infectious disease and foreign invaders. All white blood cells are produced and derived from mult ...

s and

erythrocyte Red blood cells (RBCs), also referred to as red cells, red blood corpuscles (in humans or other animals not having nucleus in red blood cells), haematids, erythroid cells or erythrocytes (from Greek ''erythros'' for "red" and ''kytos'' for "holl ...

s). However, blood filtration to recover rare circulating tumor cells without loss and without cell damage is a challenge. The ISET test uses a specially designed device and specially designed filters to allow the elimination of all erythrocytes and most leukocytes from the sample, making the subsequent cytopathology process significantly easier and more accurate. Figure 2, Tumor and non tumor cells are present in blood

Figure 2, Tumor and non tumor cells are present in blood

History

The ISET technology was first reported in 2000 in the ''American Journal of Pathology'' by the team of Professor

Patrizia Paterlini-Bréchot Patrizia Paterlini-Bréchot, born in the Italian city of Reggio Emilia, is an Italian scientist and a professor of cell biology and oncology working at the Faculté de Médecine Necker-Enfants Malades, Université Paris Descartes and at INSER ...

. Since the first report in 2000, over 80 scientific articles have been published using the Rarecells System verifying the findings of the initial developers. From 2005 to 2008, the device operating the ISET process was distributed by Metagenex. In 2009 Metagenex gave back the licences of the ISET patents to its developers: INSERM, University Paris Descartes and AP-HP. Paterlini-Bréchot then founded the company Rarecells"ISET Publications"
by Rarecells in '' Rarecells Diagnostics''. which, since 2010, has the exclusive licence of the ISET patents, distributes the ISET products and develops the ISET tests.

Sources

{{reflist Medical tests Cancer screening