[Clinical significance of enrichment and detection of circulating tumor cells in NSCLC patients with immunomagnetic beads].

OBJECTIVE: To investigate the feasibility and clinical significance of detection of circulating tumor cells (CTCs) in peripheral blood of NSCLC patients by lung cancer cell immunomagnetic enrichment and detection kit. METHODS: Four groups of patients (Group A: 18 cases with stage I lung cancer; Group B: 33 cases with stage II - IV lung cancer; Group C: 20 cases with benign pulmonary diseases; Group D: 20 healthy volunteers) were enrolled for detection of CTCs using the lung cancer cell enrichment and detection kit developed by ourselves, and compared with the results obtained using simple ICC method and the detection of CK19 mRNA and LUNX mRNA using nested PCR as control. RESULTS: By using lung cancer cell enrichment and detection kit, it was revealed that the detection rates of CK positive cells were 33.3%, 60.6%, 0% and 0% in Group A, B, C and D, respectively. By using nested RT-PCR, the rates of positive expression of CK19 mRNA were 38.9%, 63.6%, 20.0% and 0% in Group A, B, C and D, respectively, and those of LUNX mRNA were 44.4%, 69.7%, 10.0% and 0%, respectively, while the detection rate of CTCs was negative in all groups using simple ICC. There was a significant difference between the results obtained by lung cancer cell enrichment and detection kit and simple ICC method (P < 0.05), while no significant difference was found between the results obtained by lung cancer cell enrichment and detection kit and nested RT-PCR (P > 0.05). There was a significant difference in the detection rates of CK positive cells between group A and groups B, C, D (P < 0.05). The micrometastasis in peripheral blood was closely related with pathological types, cell differentiation and TNM staging (P < 0.05). CONCLUSION: The lung cancer cell enrichment and detection kit developed by ourselves is a sensitive and reliable method to detect CTCs in patients with NSCLC. It may be helpful in diagnosis of NSCLC micrometastasis and circulating tumor cells in peripheral blood, re-determination of clinical stage and provide important information for cancer-therapy personalization.