title: Dose KRAS Mutation Status Affect on the Effect of VEGF Therapy in Metastatic Colon Cancer Patients?
abstract: OBJECTIVE
  Mutations affecting the KRAS gene are an established negative predictor for anti-epidermal growth factor receptor (anti-EGFR) therapies in metastatic colorectal cancer (CRC). However, the role of KRAS mutation as a biomarker for anti-vascular endothelial growth factor (VEGF) remains controversial.
  
  
  METHODS
  We analyzed retrospective data from 32 CRC patients who were available for KRAS mutation status and received cytotoxic chemotherapy plus bevacizumab as a first-line therapy. Six of 32 patients received anti-EGFR therapies. We used KRAS mutation status as a predictive or prognostic factor in CRC patients receiving bevacizumab.
  
  
  RESULTS
  We observed mutations in KRAS in 59.4% of patients. Bevacizumab was used in combination with oxaliplatin based regimens. There was no significant difference for progression free survival (PFS) and overall survival (OS) in patients with oxaliplatin based cytotoxic chemotherapy plus bevacizumab according to the status of KRAS mutation. After first-line therapy, 28 patients (87.5%) received second-line therapy. In univariate analysis, KRAS mutations did not have a major prognostic value for PFS (hazard ratio, 1.007; 95% confidence interval [CI], 0.469 to 2.162; p>0.05) or OS (hazard ratio, 0.548; 95% CI, 0.226 to 1.328; p>0.05). In addition, anti-EGFR therapies did not affect the impact on OS.
  
  
  CONCLUSIONS
  KRAS mutation is neither a predictive for bevacizumab nor a prognostic for OS in CRC patients receiving anti-VEGF therapy.
authors: Division of Hematology-Oncology, Department of Internal Medicine, Korea University College of Medicine, Seoul, Korea. ; Division of Hematology-Oncology, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors: Seung Tae
authors: ST
authors: Kim
authors: Division of Hematology-Oncology, Department of Internal Medicine, Korea University College of Medicine, Seoul, Korea.
authors: Kyong Hwa
authors: KH
authors: Park
authors: Division of Hematology-Oncology, Department of Internal Medicine, Korea University College of Medicine, Seoul, Korea.
authors: Sang Won
authors: SW
authors: Shin
authors: Division of Hematology-Oncology, Department of Internal Medicine, Korea University College of Medicine, Seoul, Korea.
authors: Yeul Hong
authors: YH
authors: Kim
keywords: Colonic neoplasms; KRAS; Vascular endothelial growth factor