Recurrence of triple-negative breast cancer (TNBC) occurs in around 30% of patients within 3 years of treatment. For some TNBC patients, recurrence occurs on average 2.6 years after treatment, while for others recurrence does not occur early. TNBC patients can therefore be divided into two groups: those with early recurrence and those who respond well to treatment.

At present, there are no biomarkers to differentiate these two groups. Some studies suggest that radiation-induced inflammatory cytokines may stimulate the development of new metastases. Gene expression profiling or protein signatures have not been able to define such biomarkers.

The aim of this research protocol is to recruit patients to evaluate if the elevation of the cytokines IL-1β, IL-5 and IL-6 in plasma collected during radiotherapy can be used to predict TNBC patients at high risk of recurrence.

Inclusion Criteria:

Women with TNBC breast cancer who meet the following criteria:

• Women aged 18 and over;
• Any tumor size (pT stage);
• Regional lymph node pN0 to pN3;
• Patient with pathologically confirmed TNBC (estrogen and progesterone receptor negative and HER2 negative);
• Neo- or adjuvant chemotherapy followed by radiotherapy;
• No evidence of distant metastasis at time of diagnosis;
• Primary tumor removed by conservative surgery with negative margins;
• Patient covered by the French social security system (for French patients).

Exclusion Criteria:

• Distant metastasis at the time of diagnosis;
• Pregnant or breast-feeding women;
• Woman deprived of liberty, under guardianship or trusteeship.
• Patient unable to give consent
• Patient unable to speak French
• Patients unable to undergo regular long-term surveillance.