Royal Prince Alfred Hospital Royal Prince Alfred Hospital
Radiation Oncology

Radiotherapy for Colorectal Cancer

Treatment of colorectal cancer may involve surgery, chemotherapy and radiation therapy, or a combination of these treatment methods.

Radiotherapy is used as a localised treatment to destroy or debulk a tumour prior to or after surgery. This allows the surgeon to more readily remove the tumour and reduce the chance of local recurrence. Chemotherapy is used as a systemic treatment to eradicate cancer cells that have or may have spread to other parts of the body.
The treatment course received by a patient depends on a variety of factors; including the type of tumour (histology), location, stage of the disease, your general health and age.
Your Radiation Oncologist will advise you what regime is most suitable for you, how effective the therapy will be and how the treatment will affect you.
Pre-planning requirements
Your Radiation Oncologist will request pre-scanning requirements, including a comfortably full bladder and empty rectum. Please empty your bladder 30 mins before your appointment time and drink approximately 500ml of water. You will be required to do this for every session of treatment.
What should you bring to your Radiotherapy Planning appointment?
  • A referral letter from your doctor (if not already submitted)
  • Medicare card
  • All private scans relating to your current diagnosis 
  • A list of your current medications (including any medication allergies)
What happens during Planning?
When you come into the Radiation Oncology Department, please report to the reception area. You will be guided to the waiting room where you will be met by your Radiation Therapists. Your Radiation Therapists will introduce themselves and ask you to confirm your identity by asking you to state:
  • your full name,
  • date of birth, and
  • the body site you will be having treatment to.
You will find that this identification process is repeated multiple times during your treatment. This is because correct identification of patients is crucial to ensure that the correct treatment is given to the correct patient. 
After correct identification, your Radiation Therapist will briefly explain the planning procedure and give you the opportunity to ask questions. You will then be shown to the change rooms to change into a gown. You will then be escorted to the Radiotherapy Simulation and Planning area where your Radiation Therapists will position you on the CT scanner bed.
Typically, you will be lying on your abdomen on an immobilisation device called a belly-board. This particular immobilisation device is used to reduce the exposure of small bowel to radiation. The bellyboard resembles a hard mattress with a large cavity for you to rest your stomach in. It is important that you are stable and comfortable in this position for the duration of your Radiotherapy Planning (up to 30 mins) and later for each of your Radiotherapy sessions. 

Patient lying in position for the CT scan

The Radiation Therapists will also ensure that you are lying as straight as possible on the CT scanner bed. They will do this using the lasers situated in the CT scanner room. This process will also be repeated at each of Radiotherapy sessions. 
Once your Radiation Therapists have positioned you, they will draw some marks on your skin. 
You will then undergo a CT scan in the treatment position. It is very important that you breathe normally and lie very still during the CT scan as any movement can affect the quality of the scans and you may then need to have the scans repeated.
Once the scan is complete, your Radiation Therapists will make three of the marks on your skin permanent with tattoos. This is done so they can use these marks as a reference to position you in exactly the same way for each day of your Radiotherapy. The tattoos are permanent and will be approximately the size of a small freckle. They will be made with a shallow skin prick using a sterile needle and a dab of black ink. In the long term they will appear as black or blue dot. 
Your Radiation Therapists will then take photos of the area to be treated and your face for identification purposes. These will be attached to your treatment plan and medical records.
Your Radiation Oncologist will be present during the planning session which takes approximately 30-45 minutes.
At the end of the Radiotherapy Planning session you will be given an appointment card which will contain details of your first treatment (date and time).
Your Radiation Therapist will then escort you back to the change rooms. When you have collected all of your belongings, your Radiation Therapist will show you the location of the treatment waiting room. This is where you will wait for your treatment every day once Radiotherapy starts.
You will also be shown how to scan your card at the front desk barcode scanner which you will use every day when you arrive for treatment. This is how you will notify the treatment staff of your arrival in the Department.
What happens during Treatment?
When you come in for your first treatment, you will need to scan your card at the front desk and take a seat in the waiting room.
One of your Radiation Therapists will call your name when they are ready to treat you.
Your Radiation Therapist will introduce themselves and ask you to confirm your identity by asking you to state:
  • your full name,
  • date of birth, and
  • the body site you will be having treatment to.
As with planning, you will be required to have a comfortably full bladder and empty rectum for treatment every day. Please empty your bladder 30 minutes before your appointment time and drink approximately 500ml of water. It is very important to make sure you do this every day.
Your Radiation Therapist will then sit down with you to discuss the treatment process, and expected side effects relating to your treatment. You will have already discussed side effects with your Radiation Oncologist but if you have any questions please feel free to ask your Radiation Therapist who will answer your questions to the best of their knowledge. If necessary they will refer you to the appropriate member of your treatment team who can provide you with further information. 
Your Radiation Therapist will take you to your treatment room and you will be asked to lie on the treatment bed in the same position as you were in your planning session.
Your Radiation Therapists will then dim the lights so that the laser beams in the room can be seen clearly. These will be used to guide the radiation therapists in setting you up in the exact same position every day.
The radiation therapists may feel for your bones and move you slightly when they are setting you up. It is important that you do not try to help unless asked as usually only millimetre adjustments will be made. 

The bed and machine will then be moved into the treatment position. The machine may come close to you, but will not touch you at any point during the treatment process.

 Patient having radiotherapy


When your Radiation Therapists are ready to turn the machine on, they will let you know and then leave the room. You will hear a doorbell sound as they leave.
Just stay nice and still and breathe normally.
There are cameras and a microphone inside the room and your Radiation Therapists will use these to monitor you throughout the treatment. If you need your Radiation Therapists for any reason, wave your hand or call out and your Radiation Therapists will come straight in.
When the treatment is over, your Radiation Therapist will come back into the room and assist you off the bed.
Although the actual treatment only takes a few minutes, the whole treatment session (from positioning to finishing treatment) may take about 10-20 minutes each day.
During the course of Radiotherapy, you will see your Radiation Oncologist or another doctor on your treatment team once a week on a set review day. This is important as it allows them to monitor your progress and address any concerns you may have about your treatment. Please allow for more time on this review day as your visit to the hospital will be slightly longer.
Due to individual treatment regimes and medical circumstances, side effects will vary from person to person and are specific to your customised plan.
Your Radiation Oncology medical team will see you once a week during your treatment to monitor your progress and to help manage any side effects.
If you have any problems between these visits please speak to your Radiation Therapist who will contact your doctor for you as needed.
Some of the possible side effects are listed in the table below. These side effects usually occur one week into treatment or may appear during the course of your treatment.
Many of these side effects can be managed and will gradually disappear after your treatment has finished.
Please let your treating team know if you develop any of these symptoms so they can be managed promptly and effectively and you are more comfortable.

     Side effects
     What can help?  
     Fatigue (tiredness)
     Most patients experience reduced energy levels, tiredness and lack      of motivation soon after starting treatment. Just listen to your body      and rest if needed. 
     Some people find exercise is beneficial.
     Dry, red, itchy skin (in      the treatment area)
     Skin reactions tend to appear after about two weeks of treatment      and may develop even further to become itchy and tender as the      treatment continues.
     The skin reaction is similar to that of sunburn; it may become pink,      and may feel warm to touch with mild discomfort.
  • Use a mild or moisturising soap
  • Bathe using lukewarm water, and avoid scrubbing in the treatment area.
  • It is not recommended to wet shave in the treatment area, but an electric razor can be used.
  • Your doctor may prescribe creams/ ointments to help relieve severe itchiness - particularly common in the perineal area (this is the area between the scrotum and the anus).
  • If the skin peels, then dressings may be helpful. Your doctor or nursing team will organise this for you.
  • If the anal canal is in the treatment field, salt baths may be beneficial. The nursing staff will advise you on management of this symptom.
     Hair loss (in the      treatment area)
     Hair loss normally occurs after about two weeks of treatment.      Usually temporary but may be permanent.
     Sense of urgency and      frequency of bowel      motion, and/or crampy      pains in the abdomen
     If experiencing diarrhoea, the oncologist can prescribe anti-     diarrhoeal medication. Also increase your fluid intake and reduce      fibre intake. Please click here for Dietician Information Guide.
     If experiencing urinary problems such as burning and/or cramping      try and drink plenty of fluids. Advise your doctor, nurse or radiation      therapist if any problems present. These symptoms can be eased      with simple medication.
     *Please let your doctor know if you experience these symptoms.
     Nausea (feeling sick)
     Patients may experience nausea, during and immediately after      treatment.
  • It is important to discuss these symptoms with your doctor
  • Your doctor may prescribe you medication to assist in reducing the nausea
  • Maintain your fluid intake and nutrition; it is advised that you try to eat small amounts of food as often as can be tolerated.
  • Avoid greasy fatty foods.
  • Avoid foods with strong odours.
     Please click here for Dietician Information Guide.
     Loss of appetite
     Small frequent meals are better tolerated.

For females only:
    • May develop some discomfort and itchiness in the vaginal region
    • Vagina may become narrower and dryer.
      • This can be managed and prevented in many cases. Please speak to your doctor or nursing staff about this.
    • Early menopause/ Infertility
[Any further concerns speak to your doctor or nursing staff in the department]
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