Hsueh-Ju Lu1,2,3, Jen-Kou Lin4,2, Wei-Shone Chen4,2, Jeng-Kai Jiang4,2, Shung-Haur Yang4,2, Yuan-Tzu Lan4,2, Chun-Chi Lin4,2, Shih-Ching Chang4,2, Hao-Wei Teng5,6,2. 1. Division of Hematology and Oncology, Show Chwan Memorial Hospital, Changhua, Taiwan. 2. School of Medicine, National Yang-Ming University, Taipei, Taiwan. 3. Program in Molecular Medicine, School of Life Sciences, National Yang-Ming University, Taipei, Taiwan. 4. Division of Colon and Rectum Surgery, Department of Surgery, Taipei Veterans General Hospital, Taipei, Taiwan. 5. Division of Medical Oncology, Department of Oncology, Taipei Veterans General Hospital, Taipei, Taiwan. 6. Institute of Clinical Medicine, National Yang-Ming University, Taipei, Taiwan.
Abstract
INTRODUCTION: Left- and right-sided colon cancers were significantly different in epidemiologic, clinical and histological parameters. However, the impact of primary tumor location in metastatic colon cancer treated with front-line targeted triplet regimens is unclear, particularly in Asian populations. METHODS: A total of 121 patients with KRAS exon 2 codon 12/13 wild-type metastatic colon cancer were enrolled between January 2007 and December 2013. All patients received one target agent, such as cetuximab or bevacizumab, as a front-line targeted triplet regimen. The impact of primary tumor location for cetuximab and bevacizumab groups was analyzed, respectively. RESULTS: In cetuximab group, left-sided metastatic colon cancer was superior to right-sided metastatic colon cancer in objective response rate (70.1% vs 33.3%, P = 0.024), progression-free survival (15.0 vs 5.3 months, P < 0.001) and overall survival (35.8 vs 14.4 months, P = 0.031). Primary tumor location was an independent prognostic factor for progression-free survival (hazard ratio 0.240, 95% confidence interval 0.114-0.508, P < 0.001). However, in the bevacizumab group, there were no differences in outcomes for either side. Primary tumor location was insignificant for progression-free survival and overall survival in univariate analysis. CONCLUSION: Left-sided primary tumors were favored in cetuximab-based front-line targeted triplet regimen for metastatic colon cancer.
INTRODUCTION: Left- and right-sided colon cancers were significantly different in epidemiologic, clinical and histological parameters. However, the impact of primary tumor location in metastatic colon cancer treated with front-line targeted triplet regimens is unclear, particularly in Asian populations. METHODS: A total of 121 patients with KRAS exon 2 codon 12/13 wild-type metastatic colon cancer were enrolled between January 2007 and December 2013. All patients received one target agent, such as cetuximab or bevacizumab, as a front-line targeted triplet regimen. The impact of primary tumor location for cetuximab and bevacizumab groups was analyzed, respectively. RESULTS: In cetuximab group, left-sided metastatic colon cancer was superior to right-sided metastatic colon cancer in objective response rate (70.1% vs 33.3%, P = 0.024), progression-free survival (15.0 vs 5.3 months, P < 0.001) and overall survival (35.8 vs 14.4 months, P = 0.031). Primary tumor location was an independent prognostic factor for progression-free survival (hazard ratio 0.240, 95% confidence interval 0.114-0.508, P < 0.001). However, in the bevacizumab group, there were no differences in outcomes for either side. Primary tumor location was insignificant for progression-free survival and overall survival in univariate analysis. CONCLUSION: Left-sided primary tumors were favored in cetuximab-based front-line targeted triplet regimen for metastatic colon cancer.