CORRELATION OF HISTOPATHOLOGIC RESPONSE AND PROGNOSTIC MARKERS WITH THE SURVIVAL IN LOCALLY ADVANCED NON-SMALL CELL LUNG CANCER PATIENTS TREATED WITH NEOADJUVANT CHEMOTHERAPY

Objective: We aimed to determine the response and prognosis to neoadjuvant chemotherapy in patients with stage III non-small-cell lung cancer (NSCLC) who had received neoadjuvant therapy and to determine the relationship with prognosis and treatment response of the expression of excision repair cross-complementation group 1 protein (ERCC1) and Ribonucleotide reductase regulatory subunit M1 (RRM1) protein. Material and Methods: Twenty-seven patients with stage III NSCLC who received neoadjuvant chemotherapy and had been operated between 2003 and 2013 were included in this study. Lung tissue biopsies were evaluated by immunohistochemical methods for ERCC1 protein expression in patients who received cisplatin and RRM1 protein expression who received gemcitabine. Results: Median age was 59 (45-75). Nineteen patients (70.4%) were at stage IIIA and eight patients (29.6 %) were at stage IIIB. All patients received neoadjuvant cisplatin-based chemotherapy. Fifteen patients (55.6%) relapsed during follow-up. The median follow-up time was 36 months. The median disease-free survival (DFS) was 26.6 months, overall survival (OS) was 48 months. From the perspective of stage IIIA and IIIB DFS (p=0.379) and OS (p=0.69) did not differ significantly. Sixteen patients’ (59.3%) viable tumor ratio was ≤10%, 11 patients’ (40%) viable tumor ratio was >10%. When considered from this point of view DFS (p=0.16) and OS (p=0.097) showed no difference. More patients survived in the low ERCC1 expression group. Patients with low ERCC1 expression and patients with high ERCC1 expression showed no difference in terms of survival. Conclusion: Patients with high RRM1 expression showing resistance to gemcitabine and with low RRM1 expression had similar survival rates. In patients with stage III NSCLC who received neoadjuvant chemotherapy, OS and DFS durations longer than literature were found