【Objective】 To study the prognostic factors of advanced colorectal cancer (ACRC) accepting cetuximab combined with chemotherapy and effect of KRAS on efficacy of that regimen. 【Methods】 Clinical data of 102 ACRC patients

treated by cetuximab plus chemotherapy in Sun Yat-sen University Cancer Center from March 2005 to December 2008

were collected. The prognostic value of clinical factors was evaluated by univariate and multivariate analysis. The KRAS status of 45 paraffin-embedded specimens were tested and the difference in objective response rate (ORR)

disease control rate (DCR)

progress free survival (PFS) and overall survival (OS) between patients with wild type and mutant type of KRAS were compared. 【Results】 The OS of patients with cancer-associated symptom was shorter than those without (34.0 months vs 43.5 months

P = 0.03). The patients with advanced primary clinical stage had short OS (88.5 months

51.0 months and 22.5 months for clinical stageⅡ

Ⅲ

and Ⅳ

P < 0.01). The OS of patients with DCR by cetuximab combined with chemotherapy was longer than that with PD (43.5 months vs 28.0 months

P < 0.01). The KRAS status of 39 cases were tested successfully and mutant rate was 28.2% (11/39). The ORR

DCR

and PFS of wild type KRAS were all better than those of mutant type KRAS (ORR 42.9% vs 9.1%

P = 0.049;DCR 71.4% vs 36.4%

P = 0.046; PFS

5.0 months vs 2.5 months

P = 0.02). However

the difference of OS between wild and mutant type KRAS was not statistically significant (42.5 months vs 33.0 months

P = 0.80) and the status of KRAS was not an independently prognostic factor(P = 0.42). 【Conclusions】 ACRC patients with DCR by cetuximab combined with chemotherapy had good prognosis. The ORR

DCR and PFS of wild type KRAS were all better than those of mutant type KRAS

but the difference of OS was not significant and the status of KRAS was not an independently prognostic factor.