Journal of Thoracic Oncology:
August 2007 - Volume 2 - Issue 8 - p S522
doi: 10.1097/01.JTO.0000283543.49212.04
Poster Abstracts: BSTB: Prognostic Factors: BSTB: Prognostic Factors Posters, Tue, Sept 4
Background:
To investigate whether excision repair cross-complementation group 1 (ERCC1) expression as determined immunohistochemically, single nucleotide polymorphisms (SNPs) in the ERCC1 gene, and mutations of epidermal growth factor receptor (EGFR) are related to the prognosis of curatively resected non-small-cell lung cancer (NSCLC), and whether these markers are related.
Methods:
One-hundred and thirty-three consecutive patients with NSCLC who did not receive adjuvant chemotherapy after curative surgery were included in this study. Representative areas from formalin-fixed paraffin-embedded tumor samples were chosen for tissue microarray analysis. Immunohistochemistry was performed for ERCC1 and the median semiquantitative H-score was used as a cut-off. EGFR mutations (exons 18, 19, and 21) were analyzed by the direct sequencing of tumor samples. Two SNPs in the ERCC1 gene, C8092A and T19007C, were investigated on the tumor samples.
Results:
ERCC1 expression was evaluable in 130 patients and ERCC1 was found to be positive in 80 patients (61.5%). Moreover, ERCC1 was expressed more frequently in smokers and in squamous cell carcinomas. Patients with positive ERCC1 expression survived longer (median overall survival 2,742 days for ERCC1-positive vs. 1,423 days for ERCC1-negative, P=.0463). EGFR mutations were found in 27 patients (20.3%) but they were not found to affect overall survival. Interestingly, EGFR mutations were more frequent in ERCC1-negative tumors (12.5% in ERCC1-positive vs. 30% in ERCC1-negative tumors, P=.014). The SNPs in the ERCC1 gene were not associated with ERCC1 expression of the tumors and did not affect overall survival of the patients.
Conclusions:
ERCC1 expression was identified as a prognostic marker of longer survival in resected NSCLCs. In addition, EGFR mutations were more frequently found in ERCC1-negative tumors, but were not found to affect survival in our patient group.