The AJCC colon cancer staging system in the 5th edition divided colon cancer into 4 stages, including I, II, III and IV, while the 6th edition subdivided stages II and III based on the depth of tumor infiltration and the number of involved lymph glands on the basis of the 5th edition, into 7 stages, including I, IIIc, IIIa, IIa, IIb, IV and IIIb. O’Connell et al. applied the different staging methods described above to compare the survival rates of 119,363 patients with colon cancer from the NIH-NCI Surveillance, Epidemiology, and End Results (SEER) database in the United States. The overall 5-year survival rate for these patients was 65.2%. The 5-year survival rates for patients with stages I, II, III, and IV were 93.2%, 82.5%, 59.5%, and 8.1%, respectively, when the AJCC 5th edition colon cancer staging was used as the standard; the 5-year survival rates for patients with stages I, IIa, IIb, IIIa, IIIb, IIIc, and IV were 93.2%, 84.7%, 72.2%, 83.4%, 64.1%, and 8.1%, respectively, when the AJCC 6th edition colon cancer staging was used as the standard. percent, 64.1 percent, 44.3 percent, and 8.1 percent, respectively, indicating that the new staging system allows for a more accurate assessment of patient prognosis. As for patients with stage IIb, the inverse survival rate for patients with stage IIIa may be related to the different clinical treatment strategies (patients with stage IIIa receive adjuvant chemotherapy while patients with stage IIb usually do not), thus raising the controversial question of whether patients with stage II colon cancer should also receive adjuvant chemotherapy. The new AJCC colon cancer staging system will allow clinicians to better assess prognosis and guide treatment.