Adenocarcinoma

Abstract

Adenocarcinoma of the lung is an extremely complex, heterogeneous group of tumours which display an extraordinary range of clinical and biological behaviour. This diversity is reflected in the morphology of the tumour and also in the emerging data on their molecular biology. Adenocarcinomas of the lung demonstrate, in common with malignancies of other histotype, molecular features which account for the so-called hallmarks of cancer, alterations in numerous genes function which leads to consistent aberrant cell population behaviour, all of which combine, resulting in the malignant phenotype. Much of the literature on adenocarcinoma molecular biology has moved away from a focus on particular genes or pathways to employ more global genomic assays of various types. From this has emerged an almost overwhelming amount of data, huge challenges in bioinformatics and interpretation but equally huge opportunities to understand complex inter-relationships between different molecular pathways. One of the most exciting aspects of the new data on lung adenocarcinoma molecular biology is the apparent tendency for a proportion of these tumours to demonstrate the so-called oncogene addiction. The importance of a particular genetic lesion, usually, though not exclusively, an activating mutation, being the sole or dominant driver of the malignant phenotype is that pharmacological inhibition of the resultant oncogenic mutant protein can lead to spectacular clinical response to treatment. The most important genes so far identified, whose abnormal expression appears to play a dominant role in individual cases, and which offer potential therapeutic targets, include EGFR, KRAS, ALK, BRAF, HER2 and CMET. Interesting uses of molecular markers in the diagnosis and classification of lung adenocarcinoma, and correlations between tumour morphology and molecular changes complete an extensive and constantly increasing body of literature on the molecular biology of lung adenocarcinoma.KeywordsEpidermal Growth Factor ReceptorLung AdenocarcinomaEpidermal Growth Factor Receptor MutationAnaplastic Lymphoma KinaseKRAS MutationThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.