Study On Neoadjuvant Chemotherapy For ⅢA Non-small Cell Lung Cancer

Objective: The efficacy of surgery for patients with stage IIIA non-small cell lung cancer (NSCLC) is limited, and post-operative adjuvant therapy have no definitly improvement on survival till now. Many clinical studies suggested that neoadjuvant chemotherapy may improve the resectability and survival of IIIA NSCLC. We conducted a randomized trial to examine the possible benefit of neoadjuvant chemotherapy for the treatment of patients with IIIA NSCLC. In order to reveal the mechanism and potential role of neoadjuvant chemotherapy on NSCLC, We examine the expressions of proteins associated with apoptosis, proliferation and drug resistence of resected tumors of IIIA NSCLC patients received neoadjuvant chemotherapy plus surgery and surgery alone.Methods: We studied 58 patients with IIIA NSCLC. The patients were randomly assigned to received either surgery alone or two courses of platinum based neoadjuvant chemotherapy plus surgery. All patients received multimodality therapy besides surgery. We evaluated the chemotherapy response, resection rate and one year survival of the two groups of patients. The 51 resected tumors were examined the expressions of p53> bcl^ caspase-3 N PCNA and GST-Tt by means of immunohistochemistry.Results: The overall pathological response rate of patients with neoadjuvant chemotherapy was 24.1%. And compaired with patients received surgery alone, there were a higher resection rate and one year survival in patients with neoadjuvant chemotherapy. The expression of p53 was significantly correlated with response to chemotherapy. The absence of p53 and lymph node stage were predictive markers for survival of IIIA NSCLC patients treated with neoadjuvant chemotherapy. There were higher levels of caspase-3 and GST-Ti expression, lower expression of PCNA in patients with neoadjuvant chemotherapy and surgery than in patients with surgery alone. The difference of expressions of caspase-3 and PCNA were statistical significance.2Conlusions: Platinum based neoadjuvant chemotherapy can increase the whole resection rate of III A NSCLC by downstage of tumor and lymph node. Neoadjuvant chemotherapy can control the potential micrometastatic foci and may have potential impact on survival. The platinum activated apoptosis by induct the expression of caspase-3 and inhibited proliferation of lung cancer cells. And there was no prominent drug resistence developed by neoadjuvant chemotherapy.