BACKGROUNDTo study the correlation among the number of tumor-infiltrating dendritic cells (TIDC) in cancer tissues and biological behavior and prognosis in lung cancer patients.

METHODSS-100 protein expression level was determined in 39 patients with lung cancer by immunohistochemistry technique. The number of S-100 + TIDC and DNA ploidy were measured by means of flow cytometry.

RESULTSThe rate of positive S-100 protein expression was 100% in 39 patients, S-100 + cells showed typical morphology of dendritic cells. The percentage of S-100 +TIDC in patients with heteroploid (21.81%±8.18%) was significantly higher than those with diploid (16.03%±4.75%) (P=0.006). There was no statistical difference between lymph node metastasis group (20.43%±7.74%) and no lymph node metastasis group ( 19.41% ±7.76%), between tumor size greater than 3cm group ( 20.90% ±8.65%) and less than 3cm group ( 19.70% ±7.61%), between non-small cell lung cancer group (19.48%±7.98%) and small cell lung cancer group (21.74%±6.17%). No correlation was found between survival time ( 1 year , 1-3 years, greater than 3 years, respectively) and percentage of S-100 +TIDC (21.96%±8.05%, 19.47%±6.18%, 19.14%±8.76%, respectively).

CONCLUSIONSThe number of TIDC should not be chosen as an independent prognostic criterion in human lung cancer.