Treatments for stage 3 anal cancer

Last medical review:

The following are treatment options for stage 3 anal cancer. Your healthcare team will suggest treatments based on your needs and work with you to develop a treatment plan.

Chemoradiation

Chemoradiation is chemotherapy and radiation therapy given during the same time period. Chemotherapy uses drugs to destroy cancer cells. Radiation therapy uses high-energy rays or particles to destroy cancer cells.

Chemoradiation is the main treatment for stage 3 anal cancer. It leaves the muscles of the anal sphincter in place (spares the muscles). If it's possible to avoid harming or removing these muscles, your overall quality of life after treatment will be better because you will be able to have bowel movements (poop) normally.

During chemoradiation, external radiation therapy is usually given once a day, 5 days a week, for 5 to 6 weeks. Chemotherapy is given every 3 weeks.

The chemotherapy drug combination used for stage 3 anal cancer is fluorouracil (also called 5-fluorouracil or 5-FU) and mitomycin. Sometimes capecitabine is used instead of fluorouracil.

Extra radiation doses, called a radiation boost, may also be given.

Find out more about chemotherapy for anal cancer and radiation therapy for anal cancer.

Surgery

Some people diagnosed with anal cancer may have an abnormal opening or passage between the anus and the surrounding perianal skin. This is called an anal fistula, or a perianal fistula. If you have an anal fistula, you will need surgery to repair it before you start chemoradiation for stage 3 anal cancer.

If treatment with chemoradiation doesn't destroy all the cancer cells, your healthcare team may offer you surgery to remove the rest of the cancer (called salvage surgery).

An abdominoperineal resection may be used to treat stage 3A or stage 3B anal cancer. This surgery removes the rectum, anal sphincter, anus and muscles around the anus.

An inguinal lymph node dissection may be used to treat stage 3B anal cancer when it has spread to lymph nodes in the groin.

Find out more about surgery for anal cancer.

Clinical trials

Talk to your doctor about clinical trials open to people with anal cancer in Canada. Clinical trials look at new ways to prevent, find and treat cancer. Find out more about clinical trials.

Expert review and references

  • Shahid Ahmed, MD, FRCPC, PhD, FACP
  • Ahmed S, Eng C, Messick CA. Squamous cell carcinoma of the anal canal. Yalcin S, Phillip PA (eds.). Textbook of Gastrointestinal Oncology. Springer Nature Switzerland; 2019: 10:171–180.
  • Czito BG, Ahmed S, Kalady MF, Eng C. Cancer of the anal region. DeVita VT Jr., Lawrence TS, Rosenberg SA, eds. DeVita, Hellman, and Rosenberg's Cancer: Principles & Practice of Oncology. 11th ed. Philadelphia, PA: Wolters Kluwer; 2019: 64:997–1013.
  • Gotfrit J, Goodwin R, Asmis T, et al. Eastern Canadian Gastrointestinal Cancer Consensus Conference 2019. Current Oncology. 2021: 28:1988–2006.
  • National Comprehensive Cancer Network. NCCN Clinical Practice Guidelines in Oncology: Anal Carcinoma Version 1.2022. 2022.
  • PDQ Adult Treatment Editorial Board. Anal Cancer Treatment (PDQ®) – Health Professional Version. Bethesda, MD: National Cancer Institute; 2022. https://www.cancer.gov/.
  • Hosni A, Elamir A. Princess Margaret Cancer Center Clinical Practice Guidelines: Gastrointestinal: Anal. University Health Network; 2019.
  • Rao S, Guren MG, Khan K, et al. Anal cancer: ESMO Clinical Practice Guidelines for diagnosis, treatment and follow-up. Annals of Oncology. 2021: 32(9):1087–1100.
  • Stewart DB, Gaertner WB, Glasgow SC, Herzig DO, Feingold D, Steele SR. Clinical practice guidelines for anal squamous cell cancers (revised 2018). Diseases of the Colon and Rectum. 2018: 61(7):775–774.

Medical disclaimer

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