PTEN and adenocarcinoma: In contrast to the situation in colon epithelium, in a mouse model of the human OEAs that harbor inactivating mutations in the APC and PTEN genes, we found that, regardless of whether the mice had two wild type Ctnnb1 alleles or one wild type and one targeted Ctnnb1 allele, adenocarcinomas morphologically similar to human OEAs formed with 100% penetrance and no differences in latency, size, morphology, or metastatic potential of the lesions arising from AdCre-mediated targeting of the Apc and Pten genes.