This study analyzed clinical response induced by TIL in patients with renal cell carcinoma previously treated by interleukin-2. Six patients (4 men, 2 women, mean age 44.3 years) with measurable metastatic localizations have been treated by TIL reinjection (0.02 to 7.6 x 10(10) cells). TIL phenotype was a combination of CD4 and CD8 in 3 patients, predominantly CD4 in two patients and predominantly CD8 in one patient. Previous treatment by interleukin-2 induced one partial response, 2 stabilizations of the disease and 3 tumoral progressions. TIL led to an amelioration for 4 patients: 2 were in complete response, 2 were stabilized and 2 had tumoral progression and decreased. This study shows that CD4 TIL may improve an initially response induced by IL-2 therapy.