Telomerase activation in adenocarcinoma-bronchioloalveolar carcinoma.

A t present, human bronchioloalveolar carcinoma (BAC) is a disease with an evolving definition. The clinical concept of BAC needs to be re-evaluated with careful attention to the 2004 World Health Organization (WHO) criteria [1] due to major clinical implications. Series published in the literature before 2000, i.e. before the WHO definition of BAC, had not discerned a specific survival advantage and clinical behaviour for BAC as compared with other nonsmall cell lung cancers (NSCLC). Instead, existing data indicate that patients with solitary small peripheral BAC, characterised by pure lepidic growth pattern with no evidence of stromal vascular or pleural invasion, represent only 2–6% of NSCLC diseases and have 100% 5-yr survival. This survival advantage may be extended to the micro-invasive BAC according to Japanese observations [2].