Stage I

Following colon cancer surgery, the cancer is classified as a stage I colon cancer if the final pathology report shows that the cancer is confined to the lining of the colon. Stage I cancer does not penetrate the wall of the colon into the abdominal cavity, has not spread to any adjacent organs or local lymph nodes and cannot be detected in other locations in the body.

Depending on features of the cancer under the microscope, stage I colon cancer survival rates are high: approximately 90% of patients are cured with surgery alone and will not experience a cancer recurrence.

The following is a general overview of the diagnosis and treatment of stage I colon cancer. Each person with colon cancer is different, and the specific characteristics of your condition will determine how it is managed. The information on this Web site is intended to help educate you about treatment options and to facilitate a shared decision-making process with your treating physician.


Surgery to remove the cancer is the primary treatment for Stage I colon cancer. In some cases, it’s possible to completely remove a cancerous colon polyp during colonoscopy. In other cases, colon cancer surgery may involve open surgery (which involves a single large incision) or laparoscopic surgery (which involves several small incisions).

Systemic Adjuvant Therapy

The delivery of systemic treatment following local treatment with surgery is referred to as “adjuvant” therapy and may include chemotherapy, radiation or precision cancer medicines. Systemic adjuvant chemotherapy is commonly used for patients with stage II or III colon cancer but rarely with stage I colon cancer. The goal of systemic adjuvant therapy in these patients is to reduce the risk of cancer recurrence. Thus far, clinical trials have not been performed evaluating adjuvant treatment in patients with stage I cancers because of the very high cure rate achieved with surgery alone.1,2

Improvement in Predicting Need for Adjuvant Therapy: Undetectable areas of cancer outside the colon are referred to as micrometastases. The presence of micrometastases may cause the cancer to relapse following treatment with surgery alone, but physicians currently cannot predict which patients will relapse.

Adjuvant chemotherapy has been shown to decrease the risk of cancer recurrence in patients with stage III colon cancer, but benefits in patients with stage I cancer — who have a high rate of cure with surgery alone — have not been demonstrated. New methods of determining which patients with early-stage colon cancer are at highest risk of cancer recurrence may identify a subset of patients who could potentially benefit from adjuvant treatment. A test that is being used for some patients with stage II colon cancer is the Oncotype DX colon cancer test. The test estimates the risk of cancer recurrence by evaluating the activity of certain genes in a sample of tumor tissue.3

Next: Surgery for Colon Cancer

Next: Precision Cancer Medicine for Colon Cancer

Next: Radiation Therapy for Colon Cancer

Next: Stage II of Colon Cancer


1 Figuerdo A, Coombes ME, Mukherjee S. Adjuvant therapy for completely resected stage II colon cancer. Cochrane Database of Systematic Reviews. 2008;(3):CD005390.

2 Benson AB, Schrag D, Somerfield MR. American Society of Clinical Oncology recommendations on adjuvant chemotherapy for stage II colon cancer. Journal of Clinical Oncology. 2004;15:3408-19.

3 O’Connell M, Lee M, Lopatin M et al. Validation of the 12-gene colon cancer recurrence score (RS) in NSABP C07 as a predictor of recurrence in stage II and III colon cancer patients treated with 5FU/LV (FU) and 5FU/LV+oxaliplatin (FU+Ox). Paper presented at: 2012 Annual Meeting of the American Society of Clinical Oncology; June 1-5, 2012;Chicago,IL. Abstract 3512.