Biopsies of the vaccination site were obtained 48 h after the first vaccination. Biopsies of the vaccination site were obtained 48 h after the first vaccination. The number of patients with biopsies with a leukocytic infiltrate is shown for patients treated with ALVAC-CEA B7.1 alone versus with ALVAC-CEA B7.1 + GM-CSF. The leukocytic infiltrate score represents the intensity of the infiltrate (0–3) multiplied by the percentage of the biopsy with the infiltrate. Margaret von Mehren et al. Clin Cancer Res 2001;7:1181-1191 ©2001 by American Association for Cancer Research