Around 1 in 5 people diagnosed with cancer in the UK take part in a clinical trial.
A trial looking at a lower dose of chemoradiotherapy or observation for early stage anal cancer (PLATO ACT3)
This trial is for people with stage 1 anal cancer who have had surgery in the past 3 months.
Cancer Research UK supports this trial.
More about this trial
Some people are diagnosed with a very small anal cancer. This is when the tumour measures less than 1 cm and is on the outside edge of the anus. A very small anal cancer is often treated with surgery called local excision.
After having a local excision, depending on whether the cancer cells were close to the edge of the area removed during surgery, you might have regular observation, or more treatment with a combination of chemotherapy and radiotherapy (chemoradiotherapy). This is because doctors think there is a chance that some cancer cells have been left behind. Or they are worried about the cancer coming back.
This trial has 2 groups:
- observation group (for people who have no cancer cells close to the edge of the area removed during surgery)
- treatment group (for people who have cancer cells close to the edge of the area removed during the surgery)
If you are in the observation group you are monitored by your doctors. In the treatment group you have a lower dose of chemoradiotherapy. A lower dose of chemoradiotherapy has fewer side effects than the standard dose, which is used to treat more advanced anal cancer.
The main aim of this trial is to see if routine observation or lower dose chemoradiotherapy after surgery is helpful at stopping early anal cancer from coming back.
Who can enter
The following bullet points list the entry conditions for this trial. Talk to your doctor or the trial team if you are unsure about any of these. They will be able to advise you.
You may be able to join this trial if all of the following apply.
- You have an early squamous cell cancer of the anus (T1) that hasn’t spread to the lymph nodes or to other parts of the body
- You have had surgery to remove your cancer (local excision) in the past 3 months
- You have satisfactory blood tests results
- Your doctor thinks you are well enough to have chemoradiotherapy (if you are going to take part in the treatment group)
- You are well enough to be up and about for at least half the day (performance status 0, 1 or 2)
- You are at least 16 years old
- You are willing to use reliable contraception during treatment and for 6 months after if there is any possibility you or your partner could become pregnant
You cannot join this trial if any of these apply.
- Your cancer has spread to other parts of the body
- You have had chemotherapy that reached your whole body (systemic) as a treatment for anal cancer
- You have had radiotherapy to the area between your hip bones (pelvis)
- You have had treatment for another cancer in the last 2 years (your doctor can tell you more about this)
- Doctors are unable to find how close the cancer cells are from the edge of the area removed during surgery. Your doctor can tell you more about this
- You have heart problems such as angina that isn’t controlled or you have had a heart attack in the past 6 months
- You have HIV and your CD4 blood count is low. Your doctor can tell you more about this
- You have had an organ transplant
- You are not able to have an MRI scan for any reason, for example you have metal implants such as a pacemaker, surgical clips, implants, pins, plates, you have a fear of being in closed spaces (claustrophobia) or you are allergic to the dye (contrast medium) given during the scan
- You are pregnant or breastfeeding
This is a phase 2 trial. The researchers need about 90 people to take part.
This trial has 2 groups:
- observation group
- treatment group
The group you join depends on how close cancer cells are to the edge (margin) of the area removed during surgery.
You are in this group if there are no cancer cells close to the edge of the area of tissue removed during surgery.
You have no further treatment. But you have regular check ups (follow up) to see how you are and to look for signs of the cancer coming back.
You have more treatment if doctors find cancer cells close to the edge of the area taken during surgery.
First you have a CT scan. This is a radiotherapy planning scan. The scan helps the doctors know how much radiation you need and exactly where you need it. About 2 weeks later, you start radiotherapy.
You have radiotherapy every day, Monday to Friday, with a break at weekends. Each treatment takes between 10 to 20 minutes. You have 23 treatments (around 4 ½ weeks).
You also have chemotherapy at the same time. You have 2 chemotherapy drugs:
Mitomycin C is an injection you have into your vein. You have it on the 1st day of radiotherapy.
Capecitabine comes as tablets that you take twice a day, morning and evening. You take them each day you have radiotherapy.
Quality of life
You complete quality of life questionnaires:
- at the time you join the trial
- at the end of treatment (if you are in the treatment group)
- 6 weeks after entering the trial (if you are in the observation group)
- 6 weeks after the end of treatment (if you are in the treatment group)
- then after 6 months, 1, 2 and 3 years (for both groups)
The questionnaires ask about how you have been feeling and what side effects you have had. They take about 15 minutes to complete each time. You can complete the questionnaires online or on paper.
Tissues samples and scans
The trial team might ask:
- to use a tissue sample of your cancer taken when you were diagnosed (stored biopsies)
- to use a tissue sample of your cancer taken when you join this trial and if your cancer gets worse (if you have samples of tissue taken as part of your routine care)
- for your permission to look at the scans taken as part of this trial
They want to study more about anal cancer, find out who is at risk of it and who is most likely to have side effects from treatment.
You don’t have to agree to this if you don’t want to. You can still take part in this trial.
Your name and address will be removed from the scans and tissue sample. So no one will be able to identify you.
You see a doctor and have some tests before taking part. These tests include:
- a physical examination
- blood tests
- an MRI scan
- a heart trace (ECG)
You see the trial doctor every week during the time you have treatment, if you are in the chemoradiotherapy group. You have blood tests and the doctor asks about any side effects you might have.
Hospital visits after you finish treatment (follow up)
If you are in the treatment group, you see the trial doctor after 6 weeks for a physical examination and then:
- every 3 months for the first 2 years
- every 6 months for at least a year
If you are in the observation group, you see the trial doctor every 3 months for first 2 years. And then every 6 months for at least a year.
You have an MRI scan after 1 and 3 years. This is for both groups.
The trial team monitor you during the time you have treatment and you have a phone number to call them if you are worried about anything. The team will tell you about all the possible side effects before you start the trial.
Radiotherapy to the anus has short term (or acute) side effects that usually start a few days after the radiotherapy begins. And side effects that can start some months or years later (long term or late side effects).
The most common short term side effects of radiotherapy include:
- sore skin
- problems passing urine- it might be difficult or painful to pass urine or you might have some incontinence
- loss of pubic hair
- tiredness (fatigue)
- vaginal irritation
We have more information about short term radiotherapy side effects.
And information about long term radiotherapy side effects.
The most common side effects of chemotherapy include:
- a drop in blood cells causing an increased risk of infection, bruising or bleeding
- feeling or being sick
- sore mouth
We have more information about the side effects of:
How to join a clinical trial
Professor David Sebag-Montefiore
Cancer Research UK
University of Leeds
This is Cancer Research UK trial number CRUK/15/007.