UGT1A1 Combined With Pharmacokinetics of SN-38 in CPT-11-based CRT in Patients With Advanced Rectal Cancer

The study evaluates the associations between peak and valley concentrations of SN-38 with the efficacy and adverse effects of advanced rectal cancer patients carrying genotype (TA) 6 /(TA) 6 or (TA) 6 /(TA) 7 after neoadjuvant chemoradiotherapy with CPT-11.All participants will be scheduled to receive surgery 6-8 weeks after the completion of CRT. The primary end point are toxicity and pCR rate.