Advances in the understanding of lung cancer.

Lung cancers still represent an incurable group of malignancies, where we have to admit that therapy, be it surgery, chemotherapy or radiation, still fails. The emphasis in research has centered on exogenous factors causing the initiation and progression of the different types of lung cancer, especially exposure to tobacco smoke. But so far we have learned that endogenous factors play an equal, if not a more important role, in the onset of this group of diseases. Cancer arising spontaneously never appears to be due to one specific factor, but experimental cancers have been shown to do so. In this light, recent advances in molecular biology have pointed out the relevance of the role of oncogenes and tumor suppressor genes in the pathogenesis of lung cancers. It is the purpose of this paper to review these latest findings, especially from a genetic point of view.