Rectal Cancer
Rectal cancers are cancers that grow in the last part of the bowel, just before the anus (or back passage).
Around 4500 Australians get rectal cancer each year. Rectal cancer is more common in men than women.
Some of the signs of rectal cancer are:
- changes in bowel habits, including runny or smaller poo and constipation
- blood in the poo
- weight loss
- pain
- anaemia.
Treatments for rectal cancer are better than they were and this means better outcomes for people too.
Radiation Therapy and Rectal Cancer
The best person to talk to about radiation therapy for rectal 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 rectal cancer
- where in the rectum the cancer is
- other treatments tried
- the 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 Rectal Cancer
Radiation therapy is an important treatment for rectal cancer.
Doctors often use radiation therapy and chemotherapy before surgery to make it easier for the surgeon to remove the whole tumour. This increases the chances of cure. Treating teams also use radiation therapy after surgery.
Palliative radiation therapy is also good for managing pain and bleeding from tumours.
Types of Radiation Therapy used in Rectal Cancer
External Beam Radiation Therapy (EBRT)is the most common type of radiation therapy used for rectal cancer.
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 also helps with symptoms such as pain or bleeding. Radiation therapy works by killing cancer cells in the anal area which stops them from growing.
People getting radiation therapy for rectal cancer may get a 1-week course or a 5-week course. In either case people are treated daily from Monday-Friday.
The radiation oncologist will explain the differences between these 2 treatments and make a plan to best suit the needs of each person.
General 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:
- Early side effects which occur during and shortly after radiation treatment.
- Late side effects which can occur months to years after radiation treatment.
For more information, go to the Potential Side Effects page.
Early Side Effects of Radiation Therapy for Rectal Cancer
Short-term side effects from radiation therapy for rectal cancer can include:
Skin irritation: The skin around the anal area and between the buttocks 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 short term and can be helped with medications or lifestyle changes. The treatment team can provide advice to help you manage side effects.
Late Side Effects of Radiation Therapy for Rectal Cancer
Late side effects vary between people and can happen a few months to a few years after treatment.
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 function. This can cause erectile dysfunction in men and vaginal dryness and discomfort in women. Doctors may offer women a vaginal dilator to help with this.
Urinary problems: Radiation therapy may cause long-term urinary problems, such as needing to pee more often or more urgently. Rarely it causes 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.
Femoral neck or pelvic fracture: This is very rare and is when a bone in the pelvis fractures due to reduced strength.
Radiation induced small bowel obstruction.
Impaired fertility or infertility: It’s important to talk about fertility preservation before treatment starts.
Premature ovarian failure: If a woman’s ovaries are present, radiation may cause early menopause.
Second cancers: There is an extremely small risk of developing secondary cancers later in life.
People treated for rectal cancer should see their doctor often and keep an eye out for long-term side effects.
Other Useful Resources for Rectal Cancer
Find additional information about cancer types, research groups, and support groups.
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.
