title: Bevacizumab Combined with Chemotherapy Improves Survival for Patients with Metastatic Colorectal Cancer: Evidence from Meta Analysis.
abstract: BACKGROUND
  Colorectal cancer is one of the leading causes of cancer deaths in both sexes in the world. Improvement of existing therapy modalities and implementing new ones in order to improve survival of patients with colorectal cancer represents a great challenge for medicine. The aim of this paper was to assess the impact that adding bevacizumab to chemotherapy has on survival in patients with metastatic colorectal cancer, compared to the use of chemotherapy alone.
  
  
  METHODS
  Hazard ratios (HRs) with their 95% confidence intervals (CI) were determined from the studies and pooled. Two-sided p values were reported and considered to indicate statistical significance if less than 0.05.
  
  
  RESULTS
  A total of 12 studies that meet the inclusion criteria were identified in the literature search, 3 phase II studies and 9 phase III studies. Based on the random effects meta-analysis, a statistically significant improvement was identified for both overall survival (HR = 0.84; 95% CI: 0.74-0.94; p = 0.003) and progression free survival (HR = 0.64; 95% CI: 0.55-0.73; p<0.00001) in patients with metastatic colorectal cancer when bevacizumab was added to chemotherapy, compared to chemotherapy treatment alone.
  
  
  CONCLUSIONS
  The findings of this meta analysis confirm the benefit of adding bevacizumab to chemotherapy in terms of survival and progression free survival, but the magnitude of this effect is not consistent throughout the included studies. This suggests the need for further research of interaction of bevacizumab with chemotherapeutic agents as well as recognition of patients' characteristics important for the treatment selection criteria.
authors: Faculty of Medical Sciences, University of Kragujevac, Kragujevac, Serbia.
authors: Irena
authors: I
authors: Ilic
authors: Department of Pharmacology, Faculty of Medical Sciences, University of Kragujevac, Kragujevac, Serbia.
authors: Slobodan
authors: S
authors: Jankovic
authors: Department of Epidemiology, Faculty of Medical Sciences, University of Kragujevac, Kragujevac, Serbia.
authors: Milena
authors: M
authors: Ilic
mesh_terms: D000970:Antineoplastic Agents / Q000627:therapeutic use*; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D000068258:Bevacizumab / Q000627:therapeutic use*; D017322:Clinical Trials, Phase II as Topic; D017326:Clinical Trials, Phase III as Topic; D015179:Colorectal Neoplasms / Q000188:drug therapy*; D005260:Female; D006801:Humans; D008297:Male; D009362:Neoplasm Metastasis; D016019:Survival Analysis
chemical_list: D000970:Antineoplastic Agents; D000068258:Bevacizumab