Aims: To determine the feasibility of radiotherapy-associated capecitabine, irinotecan and oxaliplatin administration at five dose levels for the treatment of locally advanced rectal cancer, with or without metastasis.
Patients and methods: This was a bicentric phase I trial, including patients with locally advanced rectal cancer, with or without metastasis. Chemotherapy comprised capecitabine (1100, 1300 or 1500 mg/m2/day, every day), irinotecan (30, 40 or 50mg/m2, once per week for 6 weeks) with the addition of oxaliplatin (40 mg/m2 at level 4 or 50 mg/m2 at level 5, once per week for 6 weeks). Radiotherapy at 46 Gy plus a boost of 4 Gy was administered concomitantly.
Results: Twelve patients received four levels of dose. As a supplement to radiotherapy, the combination of capecitabine and irinotecan at the respective doses of 1500 mg/m2/day and 50 mg/m2/week was feasible and well tolerated. The addition of oxaliplatin to this combination provoked toxicity (grade 3/4 vomiting, diarrhoea) for two-thirds of the patients.
Conclusion: A treatment associating radiotherapy (46 Gy+4 Gy) with concomitant chemotherapy comprising capecitabine (1500 mg/m2/day, every day) and irinotecan (50 mg/m2/week, for 5 weeks) was feasible and well tolerated. The addition of oxaliplatin to these doses was prohibitory to the continuation of treatment due to unacceptable toxicity.