Phase II trial of capecitabine/irinotecan and capecitabine/oxaliplatin in advanced gastrointestinal cancers.

Combination protocols of 5-fluorouracil/leucovorin (5-FU/LV) plus irinotecan or oxaliplatin have demonstrated high activity in metastatic colorectal cancer. Capecitabine, an oral 5-FU prodrug, may replace infusional 5-FU/LV in combination protocols with irinotecan or oxaliplatin. We therefore initiated a phase II study with capecitabine plus either irinotecan or oxaliplatin to determine the efficacy and toxicity of specific combination protocols in patients with advanced gastrointestinal (GI) tumors. Capecitabine 1000 mg/m(2) taken orally twice a day on days 1-14, plus oxaliplatin 70 mg/m(2) on days 1 and 8, or irinotecan 100 mg/m(2) on days 1 and 8; repeated every 3 weeks in an outpatient setting. Patient and tumor characteristics were as follows: median age, 68 years (range, 34-77 years); sex: 10 women, 33 men; tumor types: 35 colorectal cancer; 8 other GI tumors including 5 gastric, 2 pancreatic, and 1 duodenal cancer. All 43 patients treated were evaluable for toxicity (capecitabine/oxaliplatin, 24 patients; capecitabine/irinotecan, 19 patients), and 39 were evaluable for efficacy (capecitabine/oxaliplatin, 22; capecitabine/irinotecan, 17). Grade 3/4 toxicities (National Cancer Institute Common Toxicity Criteria Version 2.0) were limited to diarrhea, 9 patients (capecitabine/irinotecan, n = 5; capecitabine/oxaliplatin, n = 4); hand-foot syndrome, 1 patient (capecitabine/irinotecan); nausea, 2 patients (capecitabine/oxaliplatin); vomiting, 1 patient (capecitabine/oxaliplatin); and peripheral neuropathy, 1 patient (capecitabine/oxaliplatin). No grade 3/4 myelosuppression was noted for either protocol. Capecitabine/irinotecan and capecitabine/oxaliplatin demonstrated significant clinical activity in colorectal cancer and other GI cancers as first-line and salvage therapy. Capecitabine/oxaliplatin and capecitabine/irinotecan show an excellent safety profile and clinical activity in colorectal cancer and other advanced GI tumors. The main toxicity in both arms was manageable diarrhea. This trial served as basis for a randomized multicenter phase II study comparing capecitabine/oxaliplatin and capecitabine/irinotecan as first-line therapy in patients with advanced colorectal cancer.