Our study outlines for the first time three major concepts: (i) lentiviral transduction of human pancreatic tumor cells was possible when cells were grafted directly in the pancreas, (ii) this transduction was achieved with a system targeting the tumor cells with cell surface antigens, sparing the normal cells and (iii) detectable loss of reporter gene-expressing cells obtained by viral transduction was observed with the TK/GCV anticancer system. This evidence concerns the gene TKT and neoplasm.