Chemotherapy for Colorectal Cancer

Chemotherapy uses drugs to destroy cancer cells. The drugs enter the bloodstream and travel through the body to the cancer cells. Chemotherapy may be used:

  • Before surgery—to shrink the tumor and decrease the amount of tissue that needs to be removed
  • After surgery—to kill any remaining cancer cells and decrease the risk of return
  • In combination with radiation therapy to shrink tumor
  • To help relieve symptoms of metastatic cancer and extend survival time

Chemotherapy Drugs and Delivery

There are many chemotherapy drugs. Most are a combination of drugs. The type of drugs are based on the kind of cancer and how you react to the drugs. Chemotherapy drugs for colorectal cancer may include:

  • 5-Fluorouracil (5-FU) with or without leucovorin or oxaliplatin
  • Capecitabine with or without oxaliplatin
  • Oxaliplatin
  • Irinotecan
  • Trifluridine and tipiracil

Chemotherapy for colorectal cancer is usually given through an IV. Some forms can be given by mouth. Both are delivered in cycles over a period of time. A medical oncologist will decide how many cycles of chemotherapy are needed. The medical oncologist will also work to find what combo of drugs will work best.

Side Effects and Management

Chemo drugs target fast growing cells like cancer cells. However, they can affect healthy cells as well. This can cause a range of side effects. Chemo regimen will be adjusted to have the most impact on the cancer cells and fewest effects on healthy tissue. Side effects or complications from chemotherapy may include:

  • Increased frequency and urgency of bowel and bladder function
  • Numbness, pain, or burning sensation in the the hands and feet—peripheral neuropathy
  • Nausea and vomiting
  • Diarrhea
  • Fatigue due to anemia
  • Confusion, forgetfulness

Other treatment can help to ease some side effects. Medicine, lifestyle changes, and alternative treatments may help. The chemotherapy regimen may also be adjusted if there are severe side effects. Early treatment may better control discomfort.


Benson AP, Venook AB, Cederquist L, et al. Colon Cancer. Version 2.2017. In: National Comprehensive Cancer Network (NCCN) Clinical Practice Guidelines in Oncology (NCCN Guidelines). NCCN 2017 Mar from NCCN website.
Colon cancer treatment option overview. National Cancer Institute website. Available at: Updated January 30, 2020. Accessed February 27, 2020.
Colorectal cancer. American Cancer Society website. Available at:
...(Click grey area to select URL)
Accessed February 27, 2020.
Colorectal cancer. EBSCO DynaMed website. Available at: Updated January 22, 2020. Accessed February 27, 2020.
Glynne-Jones R, Wyrwicz L, Tiret E, et al. Rectal cancer: ESMO Clinical Practice Guidelines for diagnosis, treatment and follow-up. Ann Oncol. 2017 Jul 1;28.
Rectal cancer treatment option overview. National Cancer Institute website. Available at: Updated January 31, 2020. Accessed February 27, 2020.
Systemic Chemotherapy for Metastatic Colorectal Cancer. EBSCO DynaMed website. Available at: https://www.dyname.... Updated February 14, 2020. Accessed February 27, 2020.
Last reviewed December 2019 by Mohei Abouzied, MD
Last Updated: 2/27/2020

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