IL2 and neoplasm: However, immunological manipulation using interleukin-2 (IL-2) mediate durable tumour regression in 5–10% of patients lasting 5 and 10 years, and this subgroup of patients are probably cured (Bordin et al, 2000; Fisher et al, 2000; Negrier et al, 2000; Atzpodien et al, 2002).