Overcoming resistance to chronomodulated 5-fluorouracil and folinic acid by the addition of chronomodulated oxaliplatin in advanced colorectal cancer patients

The addition of oxaliplatin (L-OHP) to a 5-fluorouracil (5-FU)/ leucovorin (FA) regimen was retrospectively evaluated in 35 consecutive advanced colorectal cancer patients after progression of disease. L-OHP, 25 mg/m2/day, was infused from 10.00-22.00 with a peak flow at 16.00 while 5-FU, 700 mg/m2/day and FA, 150 mg/m2/day of the I-form or 300 mg/m2/day of the racemic form, from 22.00 to 10.00 with a nocturnal peak at 4.00, for 5 days every 3 weeks in 24 patients and for 4 days every 2 weeks in the other 11. Diarrhea and sensitive neuropathy were the most relevant types of toxicity (17% of patients). An objective response was achieved in 8/35 patients (23%) [95% CL 9-37], stabilization in 15 patients (43%) which included five minor responses, and progression in 12. There was no relevant difference in quality of life assessed with the EORTC QLQ C30+3 questionnaire before and after treatment. Median duration of response and median progression-free survival were 6 months; median overall survival was 11 months. This retrospective study showed that it is possible to reverse resistance to chronomodulated 5-FU by adding chronomodulated L-OHP to the previous regimen; comparison with different schedules of this combination should be performed in order to identify the best tolerated and active regimen as second-line treatment of advanced colorectal cancer.