The prognosis for someone diagnosed with colon cancer is very good if the cancer is detected before it spreads, according to the American Cancer Society. If detected early enough, up to 92 percent of individuals that receive treatment live for five years or longer.
Colon cancer is divided into several different stages that represent how far the cancer has spread, according to the National Cancer Institute. If the cancer has spread to the innermost wall of the colon but remains outside of the outermost wall, then it is categorized as stage I, and the patient has the best prognosis. If it has reached the outer wall, then the cancer is said to have reached stage II. Prognosis in this stage is lower than that of the first stage, but still high at 87 percent of patients living for five years or longer. However, stage IIB colon cancer has a statistically lower five-year survival rate at 63 percent.
For later stages of cancer, namely stages III and IV, prognosis drops steadily, as stated by the National Cancer Institute. This is because the cancer in these stages has spread to the lymph nodes or other distant organs. Stage III patients face five-year survival rates ranging between 53 and 89 percent, but these rates fall to 11 percent at stage IV.