53 META-ANALYSIS OF STUDIES COMPARING ADJUVANT CHEMOTHERAPY WITH SURGERY ALONE IN NON-SMALL CELL LUNG CANCER

Thursday, October 18, 2012
The Atrium (Hyatt Regency)
Poster Board # 53
Quantitative Methods and Theoretical Developments (MET)

Helmut Sitter, PhD, University Marburg, Marburg, Germany, Eva Schmutz Jr., Institute of Surgical Research, Marburg, Germany and Gerd Goeckenjan Sr., Professor, Dr., Clinic for Pneumology, Kassel, Germany

Purpose: Lung cancer is still leading cause of cancer death in Germany with more than 40.000 deaths per year. For men it’s number one cause of cancer death, with a falling tendency during the last 10 years. For women it’s the second most cause of cancer death with a strong tendency to rise. The 5-year survival rate in Germany is 15% for men and 18% for women.[1] For non-advanced stages surgery is the main option for therapy. Our aim was to review the quality of clinical trials systematically and to summarize the evidence on this topic.

Method: A literature search was performed for prospective randomised controlled trials of adjuvant chemotherapy given because of non-small cell lung cancer. It was systematically searched in Medline and Cochrane Library from January 1980 until June 2011 with predefined search terms. Articles were selected by a two-step procedure. Each study was assessed according to their methodically quality using “Level of evidence” from Oxford Centre for Evidence-based Medicine. The relevant data of each study were extracted by two scientists independently. If the two assessments differed a consensus decision of the two reviewers was reached. Then a meta-analysis of Level 1 trials and from Level 1 together with Level 2 was performed by Review Manager (RevMan) 5.1. The common endpoint is overall survival. For comparison hazard ratio was used to show effects in forest plot. For studies without hazard ratios a calculation of the estimated hazard ratio from Kaplan-Meier curve was performed and the Parmar method was used. [2]

Result: The search identified 228 trials comparing adjuvant chemotherapy with surgery only. The meta-analysis codedadjuvant chemotherapy as experimental and included 28 studies of level 1 and 2 (involving 10403 patients). 12 of them had the highest evidence level 1 (6659 patients). The summary hazard ratio for level 1 studies is HR 0.88 (95%-confidence interval 0.82 - 0.95) with test for overall effect p< 0.001 (see figure below). For all studies 0.87 (95-%-confidence interval 0.83 -  0.93) with p < 0.001.

Conclusion: This meta-analysis showed a significant benefit for adjuvant chemotherapy compared to surgery alone. [1]  Statistisches Bundesamt Deutschland, Wiesbaden  (2007) [2] Parmar, K. M. , et al. Stat. Med. 17, 2815-2834  (1998)