The molecular approach to diagnosis in lung cancer

From Introduction: Lung cancer is the biggest cause of cancer death in the UK (CRUK, 2014). It is a biologically very diverse disease, and shows striking variation seen in histological appearances, which are reflect high levels of genomic changes with concomitant diversity of tumour cellular biology (reviewed in Shames and Wistuba, 2014). Despite this, until a decade ago, a simple classification into two categories, small cell or non-small cell, was the only one relevant to disease management. Small-cell carcinoma generally gave a good initial response to chemotherapy, whereas only non-small cell disease was amenable to surgical cure and there was no clinical reason for pathologists to attempt further classification of non-small cell carcinomas. This review will examine the subsequent developments in lung cancer diagnosis and look forward to how emerging technologies and improved understanding of tumour biology are likely to further transform the pathological diagnosis of this disease.