The addition of the chemotherapy combination consisting of Eloxatin (oxalipatin) plus 5-fluorouracil (5 FU) following surgery reduces the risk of cancer progression among patients with deficient mismatch repair (dMMR) stage III colorectal cancer. These results were recently published in the Journal of the National Cancer Institute (JNCI).
Among patients with colorectal cancer that has spread to local or regional sites, surgery remains the cornerstone of treatment. Often, patients receive chemotherapy and/or radiation therapy following surgery, referred to as adjuvant therapy. Adjuvant chemotherapy is used in an attempt to kill any cancer cells that may be remaining in the body following the surgical removal of the cancer.
5-fluorouracil, alone or in combination with other chemotherapy agents, is commonly used as adjuvant therapy for colorectal cancer. However, research has indicated that patients with cancer that has a deficiency in the ability to repair mistakes that arise in DNA during cell division, referred to as dMMR, do not respond to treatment with 5 FU.
Researchers recently analyzed data from patients with stages II and III colorectal cancer – meaning their cancer had spread outside of the colon wall, but not to distant sites in the body. The data included 433 patients with dMMR colorectal cancer who had received one of the following treatment regimens between 2000 and 2011: surgery alone; surgery plus 5 FU; or surgery plus 5 FU and oxaliplatin.
- The addition of 5 FU following surgery did not provide an improvement in outcomes compared to surgery alone.
- The addition of 5 FU plus oxaliplatin following surgery significantly delayed cancer progression compared to surgery alone.
- Only patients with stage III colorectal cancer derived benefit from the addition of 5 FU/oxaliplatin in addition to surgery.
The researchers concluded that “This study supports the use of adjuvant chemotherapy with [5 FU] plus oxaliplatin in stage III dMMR [colorectal cancer].”
Reference: Tougeron D, Mouillet G, Trouilloud, et al. Efficacy of Adjuvant Chemotherapy in Colon Cancer With.Microsatellite Instability: A Large Multicenter AGEO Study. Journal of the National Cancer Institute. 2016; 108 (7): djv438 doi: 10.1093/jnci/djv438.