Surgery was performed 4 to 8 weeks after chemoradiation , then 4 to 6 weeks later , adjuvant chemotherapy ( oxaliplatin 85 mg/m ( 2 ) ; leucovorin 400 mg/m ( 2 ) ; 5-fluorouracil 400 mg/m ( 2 ) ; 5-fluorouracil 2400 mg/m ( 2 ) ) every 2 weeks 9 .