Surgical resection following interleukin 2 therapy for metastatic renal cell carcinoma prolongs remission

Records of 399 patients with metastatic renal cell carcinoma treated with interleukin 2 with or without lymphokine-activated killer cell immunotherapy enrolled in 14 separate clinical trials from multiple institutions were reviewed to determine whether patients with a partial response to interleukin 2 therapy would benefit from surgical resection of residual tumor. Sixty-two patients demonstrated objective responses (15.5%), 18 (4.5%) complete and 44 (11.0%) partial. Eleven patients underwent resection of residual tumor in the lung, kidney, retroperitoneum, or pelvis so that they had "surgically no evidence of disease" (SNED). Of these, 10 had partial responses, and one patient with progressive disease had a complete response. Comparison of response duration showed no difference between the complete response and SNED groups, but there was a significant difference between each of these groups and the partial response group. At this writing, all 11 patients in the SNED group remained alive without evidence of disease (median follow-up, 21 months). In contrast, only 14 patients (76%) with complete responses and 15 patients (35%) with partial responses remained free of disease progression. Enhanced survival of the complete response and SNED groups compared with the partial response group borders on significance and awaits longer follow-up. These data suggest that surgical resection, if technically feasible, may benefit patients who show a partial response to interleukin 2 treatment for metastatic renal cell carcinoma.