IS IT USEFUL TO DETERMINE ERCC1 EXPRESSION IN EARLY STAGE NON-SMALL CELL LUNG CARCINOMAS?

Objective: Recent studies have been reported that expression levels of Excision-Repair-Cross-Complementing-Group-1 (ERCC1) has predictive value to anticipate the efficacy of adjuvant-platinum-based-combination-chemotherapy in patients with non-small-cell-lung-cancer (NSCLC). However, it is still controversial. The aim of this study was to compare the efficacy of immunohistochemical analysis (IHC) and real-time-polymerase-chain-reaction (RT-PCR) to determine ERCC1 expression and, whether the ERCC1 expression levels is effective to predict the clinical outcome of the NSCLC patients who were treated with by platinum-based-chemotherapy after lung resection. Material and Method: Our study is prospective and descriptive. Between January2011&2014, patients who were operated for NSCLC in Dokuz Eylul University Thoracic Surgery Clinic and who met the criteria of the study were included. Expression levels of ERCC1 were analyzed by RT-PCR and IHC. Predictive value of ERCC1-expression was evaluated by examining the results statistically in terms of recurrence and survival Results: The study was conducted on 17 cases whose mean age was 59.82±6.36 years. Two-year-survival was 82.4% when recurrence was observed in three cases. By RT-PCR analysis, 64.70% of patients were found to have ERCC1-expression-level higher than normal tissue in tumor tissue. IHC-analysis showed strong expression 35.29%. The relation between the RT-PCR and IHC score averages was not significant (p=0.14). It was determined that recurrence development of the patients correlated-well with the RT-PCR score (r=-0.29), while too poor correlation (r=0.13) was observed with IHC-scoring. Conclusion: Our study supports that determination of ERCC1 expression level by RT-PCR may be more reliable than IHC on prediction of recurrence in NSCLC. However, in order to make more accurate interpretations, there is a need for multi-centered, large-scale case studies