Biweekly oxaliplatin and irinotecan chemotherapy in advanced gastric cancer. A first-line multicenter phase II trial of the Arbeitsgemeinschaft Medikamentöse Tumortherapie (AGMT).

Background: The aim of the study was to evaluate the feasibility and efficacy of an outpatient oxaliplatin/irinotecan chemotherapy in chemonaive patients suffering from unresectable gastric cancer.
Materials and Methods: Biweekly oxaliplatin (85 mg/m2) and irinotecan (125 mg/m2) was chosen since it has been shown previously in colorectal cancer that oxaliplatin (85 mg/m2) is superior to a lower dose and toxicity of irinotecan is much lower if given fractionated. The irinotecan dose below the maximum tolerated dose takes into consideration concerns about increased toxicity in gastric cancer patients.
Results: Forty-three patients with histologically proven gastric adenocarcinoma and no previous palliative chemotherapy were selected. WHO grade 3 and 4 toxicities included neutropenia in 2/43 patients, anemia in 3/43 patients, nausea in 2/43 patients and diarrhea in 4/43 patients. Response rates were assessable in 38 patients as follows: complete response in three patients (8%), partial response in 19 (50%), stable disease in 11 (29%), and progressive disease in 5 patients (13%). The median time-to-progression was 53 months and median overall survival was 9.5 months.
Conclusion: The outpatient combination of biweekly oxaliplatin/irinotecan was well tolerated and showed a response rate within the range of other first-line combination therapies. The favorable toxicity profile, however, renders oxaliplatin/irinotecan as an alternative first-line regimen.