Oncotargeted transduction of lentiviruses is efficient only in pancreases bearing tumors. Ten μg of p24 lentiviruses carrying the luciferase reporter gene packaged into the VSV-G-containing envelope (A lateral view, B ventral view) or anti-MUC4-conjugated lentiviruses (C lateral view) were directly injected in the pancreas of tumor free animals (n = 3 animals in each group). Luciferase signal was visualized after one week. Luciferase signal intensity was quantified and is reported as mean of Ph/sr/s ± SEM (D). Increased luciferase signal is shown after 16 days in the same animals (E, F: VSV-G and G: MUC4), with signal quantification (H).