Depends on the stage
If a colon cancer
can be completely resected, this always yields the best prognosis.
If the stage is high enough that the risk of recurrence is high, adjuvant chemotherapy can be given to reduce the risk of recurrence. This is typically done for cancers that have spread to involve lymph nodes, and usually entails treatment for 3 days every 2 weeks for about 6 months, similar rx for unresectable ca.