EGFR and adenocarcinoma: Among the 75 samples that qualified for evaluation of the presence of EGFR mutations in exons 18, 19, 20 and 21 in adenocarcinoma cytological samples, 4 samples did not qualified for molecular analysis since few tumor cells were found in the cytological material (<20) or due to the fact that the low yield and poor quality of the extracted DNA material prevented the use of real-time PCR (Table II).