The Clinical Analysis Of Cetuximab Combined With FOLFOX4in The Treatment Of Metastatic Colorectal Cancer

Background and purpose: Cetuximab combined with chemotherapy as thefirst-line therapy for metastatic colorectal cancer patients with wild-type KRAS hasbeen widely recognized. Currently, Cetuximab has been combined with FOLFIRIscheme containing Irinotecan (Irinotecan+Fluorouracil/Leucovorin), and its curativeeffect has been recognized. But Cetuximab associated with chemotherapy containingOxaliplatin is controversial.At present, most people don’t think that Cetuximabcombined with FOLFOX scheme containing Oxaliplatin (Oxaliplatin+capecitabine) isappropriate. However, Cetuximab associated with FOLFOX scheme(Oxaliplatin+Fluorouracil/Leucovorin) is controversial. So we designed a randomized,controlled clinical study. In this study, mCRC patients with wild-type KRAS goneinto Cetuximab+FOLFOX4group or FOLFOX4alone group. We evaluated theefficacy and safety of Cetuximab+FOLFOX4as the first-line therapy for mCRCpatients with wild-type KRAS. And we analyzed the correlation of rash degree andcurative effect after the treatment of Cetuximab. At the same time, we observed theChinese KRAS gene status and its affecting factors.Materials and Methods: Confirmed by histopathology,102cases of initialunresectable mCRC entered preliminary screening after patients’ informed consent,and they all come from Bethune first hospital of jilin university. Their KRAS genestatuses were detected. Afterwards,50mCRC patients with wild-type KRAS andthrough all screening criteria gone into Cetuximab+FOLFOX4group (n=24) orFOLFOX4alone group (n=26). We collected patients clinical data to evaluate theefficacy and safety of Cetuximab. We also analyzed the correlation of rash degree andcurative effect after the treatment of Cetuximab and the influencing factors of KRASgene status. Results:1. The result showed that the mutation rate of the KRAS gene was32.4%and was similar with other reports in regard to Chinese.2. Different gender,age, primary tumor site, lesion morphology, histology, infiltration depth, the degree ofdifferentiation, primary lymph node and distant metastasis had nothing to do with themutation rate.3. In Cetuximab+FOLFOX4group (n=24),2cases resolvedcompletely,14cases resolved partially,4cases were stable,4cases were progress.The response rate was66.7%, the median progression-free survival time was8.3months and the median overall survival was22.5months. In FOLFOX4alone group(n=26),0case resolved completely,8cases resolved partially,12cases were stable,6cases were progress. The response rate was30.8%, the median progression-freesurvival time was6.2months and the median overall survival was18.5months. Theresponse rate of combined group was obviously better than chemotherapy group’s(p=0.035). The median progression-free surial time of combined group was longerthan chemotherapy group’s（p=0.032). The median overall survival time of combinedgroup was longer than chemotherapy group’s（p=0.193), but the difference wasn’tsignificative. The rash incidence of combined group was more superior thanchemotherapy group’s（75.0%vs0%, p<0.001). Other adverse reactions (hematologytoxicity, nausea, vomiting and diarrhea) there were no statistical difference. Most ofthe adverse reactions were lighter, and patients could put up with them.4. Theresponse rate（100%vs42.9%, p=0.015）、median progression-free surial time（16.7months vs3.0months, p=0.001） and median overall survival time（25.3months vs16.0months, p=0.033）of patients with grade2to3skin reactions were allobviously better than others’ with grade0to1skin reactions.Conclusions:1. The result showed that the mutation rate of the KRAS gene was32.4%.2. Different gender, age, primary tumor site, lesion morphology, histology,infiltration depth, the degree of differentiation, primary lymph node and distantmetastasis had nothing to do with the mutation rate.3. Combined group overallcurative effect was superior to the chemotherapy group as the first-line therapy formCRC patients with wild-type KRAS. Most of Combined group adverse reactionswere lighter, and patients could put up with them.4. The curative effect of Cetuximab was related to degree of skin reactions.