Published on 4 February 2019

Determining how each woman with breast cancer will evolve will allow them to come up with appropriate therapeutic innovations. A study conducted by researchers from Université Paris-Saclay, in collaboration with the Peter MacCallum Cancer Center in Melbourne (Australia) on a cohort of women with cancer said to be triple negative has just been published in the first international journal of Clinical Oncology, Journal of Clinical Oncology.

Women with triple negative breast cancer unfortunately do not benefit equally from the progress made in the management of these cancers in general. They remain more difficult to treat and often have a poorer prognosis. Determining for each woman how the cancer will evolve would allow them to offer therapeutic innovations whenever possible. A pooled study reveals that their prognosis can be assessed using a new biomarker (sTILs) that consists of determining the tumor's immune fingerprint at the time of diagnosis. The prognostic score is calculated by an algorithm trained on the data of more than 2,000 patients from 9 international clinical studies.

"By correlating the tumor's immune fingerprint to the patient's prognosis using the algorithm, we hope, based on their risk, to promote their participation in future clinical studies including women with triple-negative breast cancer," says Stefan. Michiels, head of the Oncostat team at Gustave Roussy.

The analysis was conducted on the basis of individual data from 2,148 patients from 9 studies in breast cancer patients in several countries. The primary objective was to examine the prognostic value of the immune fingerprint, ie the presence of lymphocytes in the extracellular tumor environment (stromal tumor-infiltrating lymphocytes or sTILs) in patients with early stage triple negative breast cancer.

The results demonstrate that the higher the lymphocyte count in the tumor at the time of diagnosis, the better the survival of these patients after adjuvant chemotherapy with anthracycline. They support the integration of the sTILS biomarker score calculation into a prognostic model for patients with early-stage triple-negative breast cancer.

The tool for calculating the biomarker score is made available free of charge to the medical community in order to be able to propose to patients, according to their risk, integrate future clinical studies.

Breast cancer remains the leading cause of cancer deaths among women under 65 years of age. Triple negative breast cancers are characterized by the absence of hormonal receptors (progesterone and estrogen) and characteristic surface protein (HER2) on the surface of the tumor; these three proteins are targets of innovative treatments (trastuzumab, targeted therapies and hormone therapy). They represent 15% of breast cancers and are of poor prognosis. Treatment options remain limited to conventional chemotherapies that are ineffective in about half of patients.

The study was mainly conducted by the Oncostat team at Gustave Roussy (Inserm U1018, Paris-Sud University, Paris-Saclay University), the Biostatistics and Epidemiology Department at Gustave Roussy and the Peter MacCallum Cancer Center in Melbourne, Australia (Translational Breast Cancer Genomics Laboratory), in partnership with Unicancer.

The project benefited from ANR and CGI funding (RHU MyPROBE, ANR-17-RHUS-0008).

The text above is taken directly from the press release