Wood and colleagues present the results from a randomized phase III trial comparing adjuvant vitespen therapy with observation alone following nephrectomy for the treatment of kidney cancer. The primary end point, recurrence-free survival, was similar in both groups. Although patients with early-stage kidney cancer tended to have improved recurrence-free survival compared with the observation group, the difference was not significant. Results for the secondary end point, overall survival, were not mature, and patients continue to be followed up. Five other randomized trials of adjuvant immunotherapy for kidney cancer have been published; all trials using cytokines failed to improve recurrence-free survival and overall survival, and only an autologous tumor cell vaccine (Reniale®; LipoNova AG, Hannover, Germany) demonstrated a significant improvement in recurrence-free survival and overall survival. Reniale® is not, however, approved for clinical use.