CTNNB1 and clear cell adenocarcinoma: Furthermore, it has been demonstrated that low-grade adenocarcinoma of the fetal lung type/well-differentiated fetal adenocarcinoma constantly shows aberrant nuclear or cytoplasmic localization of beta-catenin, whereas high-grade adenocarcinoma of the fetal lung type/clear cell adenocarcinoma with fetal lung features shows the same membranous localization of beta-catenin as conventional pulmonary adenocarcinomas, which could also be observed in the present case [1].