Molecular pathology in lung cancer: a guide to the techniques used in clinical practice

Five year survival rates for lung cancer patients are poor; however the development of new therapeutic options, which benefit subsets of the population, offer hope of improvement. These novel therapies frequently rely upon the analysis of biomarkers in pathology samples; in lung cancer patients, testing is now routinely carried out to identify small mutations and chromosomal rearrangements in order to predict response to treatment. The recent increase in biomarker analyses in pathology samples has lead to the development of a new specialty, molecular pathology. The use of molecular pathology assays in clinical samples is largely under the control of the histopathologist; who is likely to be asked, as a minimum, to select tissue sections for molecular analysis and mark areas of H&E stained slides for macro or microdissection. Many histopathologists will also be involved in the sourcing and implementation of new assays. This review aims to provide a guide to some of the most commonly used molecular pathology methods - their advantages and their limitations.