• Recurrence-free survival: loco-regional, adrenal, kidney and distant-metastases were the events considered for event-free survival.
  

• Tolerability, toxicity and safety.
  

For pts with non-metastatic RCC, no standard adjuvant treatment exists. Immunotherapy (IT) using IFN and/or IL2 is effective in metastatic disease setting. Low and chronically repeated doses of IL2 plus IFN induce a persistent stimulation of the immune system with no relevant toxicity. Surgically treated RCC pts were randomized to the following arms: A) low-dose IT; B) control arm. IT consisted of a 4-week cycle of s.c. IL2 (5 days/wk, 1 million UI/sqm bid d 1,2 and 1 million UI/sqm x 1 d 3,4,5) + IFN (1,8 million UI/sqm d 3,5 of each week). Cycles were repeated every 4 months for the first 2 years and every 6 months for the remaining 3 years. Each patient received 12 cycles in 5 years. Inclusion criteria were as follows: histological diagnosis of RCC, age <75 yrs, radical or partial nephrectomy within the past 3 months, pT1 (diameter of T > 2,5 cm), T2, T3 a-b-c; pN0-pN3, M0; good cardiac and renal function and no autoimmune disease.