Outpace the tumor with early detection

01/22/2019

Over time the tumor acquires new mutations, some of which will help the tumor become resistant to treatment. Detecting the apparition of these lesions at the early stages of the disease should limit the development of resistance.

Vaisseau sanguin - ADN circulant tumoral (ADNct) et cellules tumorales circulantes (CTCs)

Amber Anirah / SIRIC - Institut Curie | Arm designed by Freepik.com

“Liquid biopsies”, a new early detection tool

Many studies have been carried out on the later stages of cancer and metastasis in particular but the early stages haven’t been studied as much due to a lack of material. This difficulty can now be bypassed thanks to recent advances in analysis which allow us to identify the genetic and epigenetic characteristics of the tumor using circulating tumor DNA (ctDNA) and circulating tumor cells (CTC) found in the blood stream.

These techniques allow us to carry out real “liquid biopsies” as they open access to a certain amount of information that was previously only accessible by biopsy. Although these biopsies haven’t yet been incorporated into routine clinical practice they are used for research where they allow iterative sampling to be performed much less invasively than if tissue fragments were to be collected. Liquid biopsy techniques are as such a unique opportunity to capture the disease at its earliest stage.

Focusing on women with BRCA1/2 mutations

To develop this approach we are focusing on a population of women with a BRCA1/2 mutation. These mutations predispose to a significant risk of developing breast cancer (72% cumulative risk at 80 years old for BRCA1 mutation carriers and 69% for BRCA2 carriers). Mutated BRCA1/2 tumors generally have a poor prognosis and are often associated with a triple negative phenotype. Offering early detection to this at-risk population could greatly improve the management of the disease by avoiding the apparition of treatment resistant cells.

For this we propose putting in place regular monitoring of women with BRCA1/2 mutations without tumor lesions. Regular blood sampling will be carried out in order to capture the apparition of the first lesions and to identify specific markers of the early stages of the disease. The analysis techniques will include genetic and epigenetic approaches among others (exosomes, micro/macro vesicles…).

The long-term objective is to be able to offer this early detection in routine diagnosis.