Side Effects of Anal Cancer Treatment

Anal cancer treatment can cause side effects that can be uncomfortable and sometimes difficult to manage. While we are actively advocating for improved treatment regimens with lessened toxicity (which means “harms”), the current standards of care can be quite invasive. In this section, we take a look at common side effects and try to help you to better understand what to expect. Remember that side effects vary from person to person—each individual thriver may not experience all of the side effects described, and it is impossible to predict how intensely they will occur.

For your knowledge: The standard of care to treat anal cancer stages I-III is combined chemoradiation therapy, otherwise known as the ‘Nigro Protocol’. The standard of care to treat stage IV anal cancer is chemotherapy. Surgery is less commonly used for the primary treatment of anal cancer.

If you are newly diagnosed, you may not be ready for all of the information contained here. If you don’t think you are, or if you aren’t sure, please have a friend or family member look through the information first. They can then help give you the most relevant information for your situation, or at least let you know which sections you should look at now and which you can save for later.

We also include information on building your care team and the three main specialists thrivers often find helpful to include: dietitians, physical therapists, and sex therapists.

We are here to help. Please Contact Us if you have any questions or concerns. As always, make sure to discuss this information with your care team. They will be able to evaluate your own particular side effects and risks and provide you with the best care possible for your unique situation.


Radiation therapy, doctor with patient

The effects of radiation vary from person to person and it is difficult to predict the extent of the side effects you will experience. Side effects are also cumulative, and often get worse as treatment progresses.

The major side effects of radiation include (but are not limited to):

  • Fatigue
  • Diarrhea and frequent bowel movements
  • Skin soreness (much like sunburn) and scar tissue
  • Bladder irritation
  • Bone weakness, especially in the hip and pelvic regions
  • Changes in libido
  • Vitamin B12 deficiency

Learn more about potential long and short term side effects and mitigation on our Radiation Treatment page.



As with radiation, the side effects of chemotherapy vary from person to person. We provide tips on how to mitigate the major side effects at various stages of chemo, through preparing well, managing your experiences during treatment, as well as what you can do afterward.

The major side effects of chemotherapy include (but are not limited to):

  • Fatigue
  • Nausea
  • Diarrhea and constipation
  • Skin soreness and other changes
  • Anemia
  • Hair Loss
  • Nosebleeds or bleeding gums
  • Bruising
  • Loss of appetite
  • Problems with Sleeping
  • Short-term memory loss (Chemo Brain)
  • Stress

Learn more on our page about treatment and the full side effects of chemotherapy.



While the most common treatment for anal cancer is chemoradiation, some thrivers do experience surgery. Surgeries include local resection, abdominoperineal resection (APR) or ostomy.

The most common side effects of surgery for anal cancer are:

  • Fatigue
  • Loss of appetite
  • Swelling or skin infection at the incision site.

Learn more about surgery for anal cancer and how to anticipate and manage possible side effects.

Resources you may also find helpful include:

goodmanDr. Jeanne Carter’s and Dr. Karyn Goodman’s presentations from the Foundation’s educational forum.



Our three part series by Dr. Allison Palandrani, PT, DPT on how physical therapy can help with anal cancer recovery. Read how PT can help with anal cancer recovery, what to expect from pelvic floor PT and where you can find pelvic floor PT. Also, see our latest update to this series which was posted August 26, 2020.


taking care of youOur first online thriver Google Hangout: Taking Care of You: Managing Side Effects from Treatment for Anal Cancer