PTEN and adenoma: Here, we establish an allelic series of mice to afford conditional expression in the glandular epithelium of KrasG12D;Pik3caH1047R or Trp53R172H and/or ablation of Pten or Trp53. We find that KrasG12D;Pik3caH1047R is sufficient to induce adenomas and that lesions progress to carcinoma when also harboring Pten deletions.