Reduced IL-2 level concentration in patients with breast cancer as a possible risk factor for relapse.

Reduced interleukin 2 (IL-2) production has been described as one of the most frequent immune dysfunctions observed at relapse in patients with disseminated solid neoplasms. It was seen that patients treated for breast cancer (NED-no evidence of disease- at check-up) have a relapse percentage of 4.7% if the IL-2 plasmatic level is normal while the relapse percentage increased to 33.3% if it is low after a 10-12 month follow-up. This link between low IL-2 and the host immune response is a new prognostic indicator and one not strictly related to the tumour itself.