The purpose of this study is to determine association between Peripheral Immune Cells(PIC) and recurrence in stage II/III colorectal cancer

The investigators hypothesize differentiation of Peripheral Immune Cells(PIC) would result in resistance of chemotherapy and tumor local of metastatic recurrence.

The primary endpoint of this study is Disease Free Survival and the secondary endpoint is 5-year Overall Survival.

5ml peripheral blood will be sorted and counted through flow cytometry at the point of before primary treatment(surgery for colon cancers, neoadjuvant therapy for rectal cancers) , before the first chemotherapy postoperatively and 1 month after last chemotherapy.

Patients will be followed up with 3 monthly assessments in the first two years and 6 monthly assessments in the rest three years. Stratification factors include age , BMI , gender , tumor location , rectal or colon cancer stage,the chemotherapy (FOLFOX, XELOX, DeGramont or Capecitabine ),laparoscopic or laprotomy, anastomosis, concomitant medications and complications.

Inclusion Criteria:

• Clinically /Pahohistologically diagnosed as stageII/III CRC
• ECOG 0-2
• Age 18-90
• Gender both

Exclusion Criteria:

• Distant metastases noticed before or during surgery
• History of malignant tumor disease
• History of autoimmune diseases or immunodeficiencies
• History of hematological disease
• History of hepatic cirrhosis or Splenomegaly
• History of chronic kidney disease
• History of organ transplant
• History of chronic inflammatory disease
• Use of hematological drugs within 1 year prior to surgery
• Use of immunodulatory drugs within 1 year prior to surgery
• Use of chemotherapeutic drugs within 1 year prior to surgery
• Long term Use of non-steroid anti-inflammatory drugs(>6 months)
• Unable or Unwilling to undergo all the standard treatment

Stage II /Stage III Colorectal Patients