Adjuvant Chemotherapy in Clinical Local Advanced CRC Following Preoperational Therapies and pT0-3N0M0 Diagnosis

Adjuvant chemotherapy was unnecessary in pathological stage Ⅱ colorectal cancer following initial treatment of surgery without high risk factors of recurrences. The treatment efficacy of adjuvant chemotherapy for pT1-3N0M0 colorectal cancer following preoperational chemotherapy or chemoradiotherapy remains unclear. Part of clinical local advanced colorectal cancer(cTxN1-2M0), which turn out to be pT0-3N0M0 after preoperational chemotherapy or chemoradiotherapy, might not really need adjuvant chemotherapy due to the down-stage efficacy of the preoperational treatments, or the misleading by lymph nodes false-positive imaging diagnosis.

Inclusion Criteria: * preoperative clinical tumor stage III （TxN1-2M0）CRC * pathological proved CRC adenocarcinoma by endoscopic biopsy * Post operational pathological T0-3N0M0 without high risk factors of recurrence * Patient able to understand and sign written informed consent Exclusion Criteria: * Other malignant tumors history. * Complications need emergency surgery (occlusion, sub-occlusion, massive hemorrhage and abscesses). * Colorectal tumor extension towards abdominal wall and/or adjacent organ making liver R0 resection impossible immediately. * Non resectable lymph node metastasis. * American Society of Anesthesiologists (ASA) grading≥ IV and/or, Eastern Cooperative Oncology Group(ECOG) score≥ 2. * Physical or psychological dependence. * Pregnant or breast feeding women. * Not controlled pre-operational infection. * Enrolled in other clinical trials within 4 weeks. * Other clinical or laboratorial condition not recommended by investigators.