Prognostic factors in patients with non resectable metastatic colorectal cancer in the era of targeted biotherapies: relevance of Köhne's risk classification.

BACKGROUND: Köhne's prognostic classification has been previously proposed, based on performance status, alkaline phosphatase level, number of metastatic sites and white blood cells count. AIMS: To identify prognostic factors for survival and to assess the validity of Köhne's classification, in the era of targeted biotherapies, in patients treated with chemotherapy for non resectable metastatic colorectal cancer.
METHODS: A total of 290 consecutive patients were retrospectively identified in all gastroenterology units of one French county, between 2004 and 2008. Univariate and multivariate analysis for overall survival were performed using pre-treatment patient characteristics.
RESULTS: All data were available for prognostic categorization in 133 patients. Median survival was 22.1 months. The distribution and median survival for Köhne's prognostic groups were as following: good (n=73; 24.8 months), intermediate (n=35; 24.2 months), and poor (n=25; 7.0 months). The survival difference was significant between good and poor prognostic groups (p<0.01) and between intermediate and poor prognostic groups (p<0.01), but not between good and intermediate prognostic groups (p=0.5). The two independent prognostic factors of survival in multivariate analysis were performance status 0/1 (p<0.01) and white blood cells count<10×10(9)/L (p<0.01).
CONCLUSIONS: The relevance of Köhne's classification is questioned. A simplified score could be validated by largest studies, based on white blood cells count and performance status.