BACKGROUNDTo investigate the immunohistochemical detected method and the clinical incidence of the bone marrow micrometastases (BMM) in patients with non-small cell lung cancer (NSCLC) and to analyze the sensitivity and specificity and clinical application value.

METHODSBone marrow samples were collected from the anterior superior iliac spines or posterior superior iliac spines of 53 patients with NSCLC in clinical stage I to III and 15 patients in stage IV, and the BMM was detected by immunohistochemical techniques (IHC) using monoclonal antibodies AE1/AE3 against cytokeratin. Chi-square test was used statistically.

RESULTSThe IHC sensitivity could be 10⁻⁵. The BMM positive rate was 22.6% (12/53) in stage I to III and 53.3% (8/15) in stage IV, and there was a significant difference in the BMM positive rate between stage I to III and stage IV (P < 0.05). No correlation was observed between BMM and sex, age, KPS, pathology classification and cancer cell differentiation.

CONCLUSIONSThe detection of BMM by IHC is convenient, sensitive, and specific. It might be helpful to diagnose bone marrow micrometastasis in patients with NSCLC.