*5.2. Adjuvant Therapy*

Adjuvant therapy is defined by the United States National Cancer Institute (NCI) as "additional cancer treatment given after the primary treatment (surgery) to lower the risk that cancer will come back" [2], eliminating any residual microscopic cancer cells. Neoadjuvant therapy is an adjuvant therapy given before the primary treatment to make it more e ffective or easier [37]. Adjuvant therapies for CRC can be divided into five groups, i.e., radiation, hormones, targeted therapy, immunotherapy, and chemotherapy.
