Les récepteurs solubles de l'interleukine-2 au cours de la radiothérapie des cancers du sein

We assessed the relationships between soluble interleukin-2 receptor (R-IL2s) circulating concentrations and the clinicobiological characteristics of 80 breast cancer patients treated by radiotherapy. We did not evidenced significant relationships between R-IL2s concentrations before radiotherapy and patient's or tumours characteristics. However, R-IL2s concentrations were found to be positively correlated to lymphocyte levels and cumulated radiations dose during radiotherapy. Radiotherapy-induced lymphocyte lysis increases R-IL2s concentration among patients having a normal lymphocyte level (> 1,4 G/L) (P = 0.01). In recurrent breast cancer, median R-IL2s concentrations were significantly elevated when compared to recurrence-free patients: median 41,5 pM/l (range: 15,6-146.0 pM/l) for metastatic patients and 53,1 pM/l (range: 36.0-70,2 pM/l) in case of contralateral cancer versus 36,6 pM/l (range: 1-169,6 pM/l) without any event (P = 0.0002). In our series of breast cancers, mainly composed of stage I and II tumours, we found no prognostic value of initial R-IL2s concentration with regard to first recurrence.