Klin Onkol 2009; 22(1): 27-33.
Summary
Backgrounds: Combination of cetuximab and irinotecan is an effi cacious second- (and further-)-line treatment-alternative in patients with EGFR-positive metastatic colorectal cancer refractory to irinotecan. In this retrospective study we present treatment results of patients treated combination of cetuximab and irinotecan in Masaryk Memorial Cancer Institute.
Patients and Methods: Results were collected on forty-seven patients who started the therapy from July 2005 to February 2008. Primary outcomes were: response rate, time to progression and overall survival. Secondary outcomes were: treatment-related toxicity and identifi cation of any predictive and prognostic markers. P-value was based on Gehan-Wilcoxon test or chi-square test and P-values ≤0,05 were considered significant. The Kaplan-Meier method was used to estimate overall (OS) and progression-free survival (PFS).
Results: Forty-two patients were valuable for the treatment response. Objective response rate (complete and partial remission) was 35,7% (15 patients) and disease control (response and disease stabilization) was achieved in 30 patients (71,4%). The median time to progression was 6,4 months (range 1,5-25 months). On the date of statistical processing (median follow-up: 9,2 months, range 2,5-27 months) there were 26 patients alive and the median overall survival was 17,1 months. We have confi rmed correlation between the grade of the skin rush and the treatment response (p=0,05) and time to progression (p=0,01), on the other hand there was no association between EGFR expression and these parameters. The therapy was also effective in 8 of 14 patients (57%), who had documented resistance to irinotecan.
Conclusions: We have confirmed the effi cacy of cetuximab and irinotecan combination for the therapy of patients with pretreated metastatic colorectal cancer. Our results are optimistic, but have to be validated in the course of time. The existence of nonresponding patients and by reason of pharmacoeconomy, we should give attention to the new molecular predictive and prognostic markers such as: K-ras-mutation and EGFR gene copy number.
