Phase II study and biomarker analysis of cetuximab combined with modified FOLFOX6 in advanced gastric cancer

This prospective study was conducted with the Korean Cancer Study Group to evaluate the efficacy and safety of cetuximab combined with modified FOLFOX6 (mFOLFOX6) as first-line treatment in recurrent or metastatic gastric cancer and to identify potential predictive biomarkers. Patients received cetuximab 400 mg m⁻² at week 1 and 250 mg m⁻² weekly thereafter until disease progression. Oxaliplatin (100 mg m⁻²) and leucovorin (100 mg m⁻²) were administered as a 2-h infusion followed by a 46-h continuous infusion of 5-fluorouracil (2400 mg m⁻²) every 2 weeks for a maximum of 12 cycles. Biomarkers potentially associated with efficacy were analysed. Among 38 evaluable patients, confirmed response rate (RR) was 50.0% (95% CI 34.1–65.9). Median time-to-progression (TTP) was 5.5 months (95% CI 4.5–6.5) and overall survival (OS) 9.9 months. Eleven patients having tumour EGFR expression by immunohistochemistry with low serum EGF and TGF-α levels showed a 100% RR compared to 37.0% in the remaining 27 patients (P<0.001). Moreover, ligand level increased when disease progressed in seven out of eight patients with EGFR expression and low baseline ligand level. No patient exhibited EGFR amplification or K-ras mutations. Gastric cancer patients with EGFR expression and low ligand levels had better outcomes with cetuximab/mFOLFOX6 treatment.

Capecitabine in advanced gastric cancer

Since the routine introduction of chemotherapy for advanced gastric cancer in the early 1990 s, median survival for gastric cancer has improved from 3 months, with best supportive care alone, to > 11 months in recently reported Phase III trials of triplet chemotherapy. Capecitabine is an orally-active fluoropyrimidine, which is selectively metabolised to fluorouracil in tumour cells. The combinations of platinum compounds and capecitabine have been evaluated in two recent, large, Phase III trials demonstrating non-inferiority in efficacy compared with platinum plus continuous infusion fluorouracil. In view of the convenience and flexibility of patients in adjusting dosage when encountering toxicities, capecitabine is replacing continuous infusion fluorouracil as the backbone of combination chemotherapy in advanced gastric cancer patients. Future trials evaluating biologicals are now incorporating capecitabine combinations as control arms in both advanced disease and peri-operative settings in gastric cancer.