[Gene diagnosis and prognosis of mediastinal lymph node occult micrometastasis in non-small cell lung carcinoma].

OBJECTIVE

To investigate gene diagnosis of occult micrometastasis in the mediastinal lymph node in patients with non-small cell lung carcinoma (NSCLC) and to evaluate its prognostic significance.

METHODS

With mRNA expression of mucoid1 (MUC1) gene examined by RT-PCR, 168 mediastinal lymph nodes taken from 37 pN(0) (negative lymph nodes) NSCLC patients (stage Ia approximately IIb) made up the experiment group. Thrity negative lymph nodes from 14 benign lesions and 30 positive lymph nodes from 15 NSCLC patients served as control. The survival difference between MUC1 mRNA-negative and MUC1 mRNA-positive groups was compared by the chi(2) test.

RESULTS

UC1 mRNA was not identified in the negative-control group (specificity = 100%), but it was identified in 26 of 30 positive-control samples (sensitivity = 86.7%). MUC1 mRNA was identified in 16 (9.5%) of the experiment group from 12 patients whose TNM stage was up-regulated to stage IIIa. The 3-year survival rate (58.3%) of MUC1 mRNA positive group patients with occult micrometastasis in mediastinal lymph node was lower than the 88.0% of MUC1 mRNA negative group (P < 0.05).

CONCLUSION

Occult micrometastasis in the mediastinal lymph node in NSCLC patients can be diagnosed by MUC1 mRNA expression through RT-PCR. Poor prognosis in some pN(0) NSCLC patients may be associated with nodal occult micrometastasis.