Purpose: The purpose of this study was to evaluate the antitumor activity and toxicity of fixed sequences of capecitabine/oxaliplatin followed by capecitabine/irinotecan in patients with previously untreated metastatic colorectal cancer.
Patients and methods: Adult patients with histologically confirmed, previously untreated, nonresectable, locally advanced or metastatic colorectal adenocarcinoma were enrolled in the study. Patients were treated as follows: capecitabine (1000 mg/m2 orally twice daily) on days 1-14 and oxaliplatin (130 mg/m2 2-hour intravenous infusion) on day 1, followed by capecitabine (1000 mg/m2 twice daily) on days 1-14 and irinotecan (240 mg/m2 1.5-hour intravenous infusion) on day 1. Each combination was administered every 21 days during 4 consecutive cycles followed by the alternating sequence to a maximum of 16 cycles.
Results: A total of 35 eligible patients have been included in this ongoing study. Response rate (complete responses plus partial responses) was 37.1%. With a median follow-up of 9.5 months, the median time to disease progression and overall survival were 7.4 months and 16.4 months, respectively. Treatment was well tolerated, with only 6% of the patients developing grade 3/4 neurotoxicity. However, the low number of patients treated beyond 4 cycles limits the interpretation of the data.
Conclusion: The preliminary results from this ongoing study suggest the feasibility of this strategy, which resulted in promising antitumor activity with less neurotoxicity.