Somatic tyrosine kinase (TK) domain mutations of the epidermal growth factor receptor (EGFR) gene are associated with sensitivity of non-small cell lung cancer (NSCLC) to tyrosine kinase inhibitors (TKI's), however their incidence in distinct populations is not clarified...We identified a wide spectrum of somatic EGFR TK mutations reporting a relatively high incidence (15%) in NSCLC patients of Greek and Czech origin. As ethnicity seems to be a factor for the origin of these mutations, further studies in distinct populations are warranted