This will be a randomized, controlled pilot trial of patients with histological documentation of primary colon or rectal adenocarcinoma with resectable cancer, who have not received any treatments for cancer. If patient is a candidate for surgical resection, with no planned neoadjuvant chemotherapy, then the patient is eligible. All eligible subjects will be consented prior to surgery.

Part 1: Blood draw prior to surgery, followed by surgical resection, and surgical pathologic specimen will be archived. After surgery, patient will be seen in 4-12 weeks to determine if adjuvant chemotherapy is indicated, in which case patient will receive adjuvant therapy. At this visit a blood draw will be done.

Part 2: If the patient is stage 0/1/2 and no plan for adjuvant treatments, then the patient will be randomized in a 2:1 manner to EGCG 900 mg daily vs observation (standard of care) for 1 year. Patients randomized to the EGCG arm, will start EGCG within 4-12 weeks of surgery and take EGCG 450 mg PO twice a day. Blood draw will be done at 0, 3, 6, 9, 12, 15, 18 months. Colonoscopy will be done at 1 year from diagnosis, at which time normal colonic tissue biopsies as well as any resected polyps will be collected.

Inclusion Criteria:

• Cytologically or histologically confirmed of primary colon or rectal adenocarcinoma with resectable cancer, who have not received any treatments for cancer.
• Age 18 years and above
• Eastern Cooperative Oncology Group (ECOG) performance status of 0-2
• The patient is a candidate for surgical resection, with no planned neoadjuvant chemotherapy, and there is a planned surgery for the primary colorectal cancer cancer or the patient had recent resection of the primary colorectal cancer. .
• For women who are not postmenopausal (12 months of amenorrhea) or surgically sterile (absence of ovaries and/or uterus): agreement to use two adequate methods of contraception. For men: agreement to use a barrier method of contraception during the treatment period
• Hematologic, Biochemical, and Organ Function within 7 days prior to Cycle 1 Day 1: Granulocyte count > 1000/mm3, Platelet count > 50,000/ mm3, Hemoglobin > 7 g/dL; Total bilirubin < 1.5xULN; Albumin > 2.8g/dl; aspartate aminotransferase (AST) (SGOT) and alanine aminotransferase (ALT) (SGPT) \