Pre-operative IL-2 immunoprophylaxis of cancer recurrence: Long-term clinical results of a phase II study in radically operable colorectal cancer

This study evaluates retrospectively the outcome of 20 colorectal cancer pa tients radically operated (M/F 13/7; primary/recurrent 15/5; Dukes B=11; C= 6; D=3) who received pre-operative IL-2 (18,000,000 IU/daily s.c. for 3 day s) and the outcome of 40 colorectal cancer (primary/recurrent 40/0) patient s age, sex and stage-matched radically operated, as control group. After a median follow-up of 72 months, in the IL-2 pre-operative group we observed 6/20 recurrences (30%) vs. 19/40 (47.5%) in controls. Mean and median disea se-free period in patients who relapsed were respectively 21 months and 20. 5 months (range 6-36) in IL-2 group vs. 14.1 and 12 months in the control g roup (range 3-34). After a 5-year follow-up, 4/20 (20%) IL-2 treated patien ts were dead vs. 19/40 control patients (47.5%) (log-rank chi(2)=3.7, p=0.0 5). Pre-operative IL-2 administration is safe, active in preventing post-op erative lymphocytopenia and seems to improve the clinical outcome in radica lly operated colorectal cancer patients.