In lung adenocarcinomas, genetic alterations of PTEN are relatively rare and little has been reported concerning the relationship between PTEN transcriptional level and clinicopathologic features or genetic changes. This study was conducted to gain insight into clinicopathologic correlations. The transcriptional levels of PTEN were examined using real time RT-PCR and analyzed for correlations with clinicopathologic features and the mutation status of EGFR and KRAS. After confirming significant correlation for PTEN levels between macrodissected and microdissected materials (p<0.01), macrodissected samples from 115 lung adenocarcinomas were examined. There were no significant difference between the PTEN levels, divided into three ranges, and the mutation status of EGFR or KRAS. Noteworthy clinicopathologic correlations between PTEN transcriptional up/down-regulation and young age (p=0.0081, 61.7+/-8.7years versus 66.1+/-8.1years), smoking (p=0.032) and less differentiated adenocarcinomas (p=0.013) were identified. Whereas male patients demonstrated no prognostic association with PTEN levels, female cases with up-regulated PTEN expression had significantly worse survival compared with those with normal PTEN levels (p=0.0027). This study revealed distinct clinicopathologic correlations with PTEN transcriptional up/down-regulation.