Chronic peripheral neurourly with numbness of the extremities increasing gradually with the cumulative dose of oxaliplatin (from 3.8% after cycle 1 to 74.4% after 12 cycles of mFOLFOX6 and from 2.7% after cycle 1 to 71, 2% after 8 cycles of XELOX) but mainly at grade 1, 2 and gradually decreased after stopping treatment (73.1% lasted for 24 months with XELOX regimen and 94.8% with mFOLFOX6 regimen).