[The application of conventional smears and liquid-based cytologic slides of lymphatic metastasis specimens of lung adenocarcinoma acquired by fine needle aspiration to detect the expression of anaplastic lymphoma kinase protein].

To explore the feasibility of conventional smears and liquid-based cytologic slides of lymphatic metastasis specimens of lung adenocarcinoma acquired by fine needle aspiration cytology (FNAC) to detect the expression of anaplastic lymphoma kinase (ALK/D5F3) by immunocytochemistry (ICC) analysis. The lymphatic metastasis specimens of 147 lung adenocarcinoma, including 100 liquid-based cytologic slides and 47 conventional smears, were collected in this study. ALK fusion protein was detected by Roche Ventana ICC technology, which was compared with the ALK fusion gene assessed by fluorescence in situ hybridization (FISH) or reverse transcriptase-polymerase chain reaction (RT-PCR). The positive rate of ALK (D5F3) fusion protein in advanced lung adenocarcinoma acquired by FNAC was 11.6% (17/147), and 10.6% (5/47) and 12.0% (12/100) were reached in conventional smears and liquid-based cytologic slides, respectively.Among 147 cases, 57 cases including 17 positive cases and 40 negative cases were verified by RT-PCR and FISH. The whole coincidence rate reached 96.5% (55/57). The sensitivity and specificity of ALK (D5F3) fusion protein detected in lung adenocarcinoma acquired by FNAC were 94.1% (16/17) and 97.5% (39/40), respectively. The sensitivity and specificity were both 100% (5/5 of sensitivity and 10/10 of specificity) in conventional smears, while 91.7% (11/12) and 96.7% (29/30) in liquid-based cytologic slides. Conventional smears and liquid-based cytologic slides of FNAC samples can be used to perform ICC analysis of ALK (D5F3) expression in advanced lung adenocarcinoma, especially for patients who have no opportunity for surgery or whose resected samples are difficult to form cell block.