[The relation between MSI and the clinicopathologic factors of NSCLC.].

Background: To explore the relationship between microsatellite instability (MSI) and various clinicopathologic factors in non-small cell lung cancer (NSCLC) .

Methods: Ninety-four lung cancer specimens resected from patients with NSCLC were investigated. We used a very precise microdissection technique to obtain the genomic DNA from tumor tissue and paired normal tissue , followed by PCR amplification of 4 polymorphic genomic sequences (D3S1067 ,D3S659 ,D3S966 and AR) . MSI and its relationship with clinicopathological factors were analyzed.

Results: Sixty-one of 94 (64. 89 %) NSCLC patients showed MSI at single or multiple loci. Statistically significant correlation was found between MSI and lymph node metastasis (Chi-Square = 9. 945 , P = 0. 002) . MSI-positive patients had significantly shorter survival time than MSI-negative ones had ( P = 0. 0001) . Cox-proportional-hazard-regression-model analysis confirmed that MSI was a very important prognostic indicator for NSCLC patients (Chi-Square = 15. 4126 , P = 0. 0001) , and lymph node metastasis had some prognostic significance in NSCLC patients (Chi-Square = 6. 6108 , P = 0. 0101) .

Conclusions: MSI closely correlates with lymph node metastasis of NSCLC and it is a crucial factor in predicting the survival time and prognosis of NSCLC patients.