Anal Cancer


Anal cancer is an uncommon cancer that forms in the tissues of the anus. This is the opening where poo/faeces comes out.

Anal cancer can cause things like bleeding, pain, or changes in bowel habits.

When doctors find and treat anal cancer early it improves outcomes.

Radiation Therapy and Anal Cancer

The best person to talk to about radiation therapy for anal cancer is a radiation oncologist. A radiation oncologist is a specialist doctor who is part of the team that takes care of people having radiation therapy.

You can ask your doctor for a referral to a radiation oncologist to learn if radiation therapy is an option for you.

The Treatment Team

Doctors make a treatment plan for each person based on the:

  • type of cancer
  • where the cancer is
  • what other treatments have been tried
  • person’s health.

The type of treatment a person gets is worked out by a team of doctors and health professionals often called a Multidisciplinary Team.

A highly trained radiation oncology team takes care of people having radiation therapy. This includes radiation oncologists, radiation therapists, medical physicists and radiation oncology nurses.

Treatments for Anal Cancer

Treatments available for anal cancer include surgery, radiation therapy and chemotherapy.

Types of Radiation Therapy Used for Anal Cancer

External Beam Radiation Therapy (EBRT) is the most common type of radiation therapy treatment used for anal cancer.

The treatment team use a machine called a linear accelerator to do external beam radiation therapy from outside the body.

Radiation oncologists often use Volumetric Arc Therapy (VMAT), which is an advanced type of external beam radiation therapy, to carefully deliver radiation to treatment areas.

This technique allows the radiation oncologist to target the radiation on the cancer while limiting radiation to healthy parts of the body.

Radiation therapy has a very important role in treating anal cancer. Treatment teams use it as the main treatment for advanced anal cancer and when they cannot operate.

It can also help with symptoms such as pain or bleeding. Radiation therapy targets cancer cells in the anal area to destroy them or prevent them from growing further.

Radiation therapy can be used with other treatments like chemotherapy or surgery, depending on the stage and where the cancer is.

People usually get radiation therapy for anal cancer over several weeks, with daily treatments from Monday to Friday.

A standard course of radiation therapy for anal cancer is usually 5 – 6 weeks, with a total of 25 to 30 treatments.

However, the number of treatments and length may vary based on how well a person is responding to treatment and their situation.

General Information About Side Effects of Radiation Therapy

Radiation therapy is more effective with fewer side effects than ever before.

Recent advances mean radiation oncologists can effectively treat the cancer while getting less radiation on healthy body parts. This means much fewer side effects.

Side effects from radiation therapy vary between people, even for those having the same treatment.

While some people feel no side effects, some feel mild side effects, such as tiredness or skin redness during and/or just after treatment. These usually get better within a few weeks.

The treatment team will offer advice and medicine to help with side effects.

Serious side effects that start later (months to years after the radiation therapy) are rare.

Before starting treatment, your radiation oncologist will talk to you about side effects and answer your questions.

The side effects of radiation treatment can be split into 2 groups:

  1. Early side effects which occur during and shortly after radiation treatment.
  2. Late side effects which can occur months to years after radiation treatment.

For more information, go to the Potential Side Effects page.

Short-term side effects from radiation therapy for anal cancer can include:

Skin irritation: The skin around the treated area may become red, dry, or itchy. This can feel like sunburn.

Fatigue: Feeling tired is common during radiation treatment, as the body works to heal.

Diarrhoea: Radiation can upset the digestive tract. This can lead to loose or watery poo.

Nausea and vomiting: Some people may experience queasiness or vomiting.

Urinary discomfort: Radiation near the pelvic area can cause discomfort or a need to pee more often.

Hair loss: Radiation will only cause hair loss in the treated area.

These side effects are usually temporary and can be managed with medications or lifestyle changes. The treatment team can provide advice and medication to manage side effects.

Late side effects vary between people and can happen a few months to a few years after treatment. Serious late side effects are rare.

These side effects may never occur, occur once, continue over time, or come and go.

Bowel problems: Radiation therapy can cause long-term bowel issues such as diarrhea, constipation, or changes in bowel habits.

Sexual dysfunction: Both radiation therapy and surgery can affect sexual health and function. For example, it can cause vaginal dryness and discomfort in women.

Urinary problems: Radiation therapy may cause long-term urinary problems, including urinary urgency, frequency, or incontinence.

Lymphoedema: Surgery or radiation therapy can damage lymph nodes, leading to lymphoedema, which is swelling in the legs due to a build-up of lymph fluid.

Radiation induced small bowel obstruction: This happens if radiation treatment causes a blockage of the small bowel.

Impaired fertility or infertility: It is important to talk about fertility preservation before treatment starts.

Premature ovarian failure: If a woman’s ovaries are present, radiation may cause early menopause.

Femoral neck or pelvic insufficiency fracture: This is very rare and is when a bone in the pelvis fractures due to reduce strength.

Second cancers: Cancers caused by radiation therapy are a very rare side effect that can occur more than 10 years after treatment.

People treated for anal cancer should continue to see their doctor regularly and let their doctor know of any symptoms.

Find additional information about cancer types, research groups, and support groups.

Further Information
You can ask your Surgeon or General Practitioner for a referral to a Radiation Oncologist for a discussion about whether radiation therapy is a suitable treatment option for you.

Radiation Oncologist

The best person to talk to is a radiation oncologist. You can ask your doctor for a referral to find out if radiation treatment is right for you.

GPs and Health Professionals

Information for any health professional involved in a patient's cancer care with a particular focus on primary care providers.

Talking to Your Doctor

Your GP or other doctors in the cancer team can organise a referral to a radiation oncologist.

Treatment Centres

Search and find your closest Radiation Oncology Treatment Centre.

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