Advances in the diagnosis of lung cancer: contribution of molecular biology to bronchoscopic diagnosis

Purpose of review Considerable advances in genomics, transcriptomics and proteomics have in the recent years transformed our understanding of the molecular mechanisms involved in the pathogenesis of lung cancer and are in the process of revolutionizing our approach to its diagnosis and treatment. Although these techniques have traditionally been described in the context of large volume biopsies from surgically resected tumors, significant technical advances allow their application to smaller samples obtained bronchoscopically, often the only samples available in advanced lung cancer. Recent findings Recent data support the use of advanced molecular techniques as an adjunct to conventional histologic examinations of bronchoscopy specimens in the following situations: early diagnosis and screening of nonsmall cell lung cancer by fluorescent in-situ hybridization techniques in particular; accurate histologic diagnosis via novel immunohistochemistry markers; and prognosis and prediction of response to targeted and conventional chemotherapeutic agents. Summary Molecular biology techniques are increasingly applied to smaller biopsy specimens obtained via bronchoscopy, allowing for their use in advanced, unresectable nonsmall cell lung cancer. Although these techniques have not yet entered the clinical practice arena, they will likely become an unavoidable complement to conventional morphologic examinations and allow for individualized diagnostic and therapeutic approach to lungcancer patients.