Bowel (Colorectal) Cancer
Radiotherapy for bowel (colorectal) cancer
Radiotherapy (exposure to high energy rays or radiation) is one of the four main treatments for cancer of the rectum (back passage); radiotherapy is seldom used to treat cancer of the colon.
Radiotherapy is typically used either before surgery to shrink a tumour to make it easier for the surgeon to remove (neo-adjuvant radiotherapy), or after surgery to lower the risk of the cancer returning (adjuvant radiotherapy). Radiotherapy treatment can be administered from outside the body (external radiotherapy) or from inside the body (internal radiotherapy).
Side effects of radiotherapy
Side effects of radiotherapy can occur during treatment or develop as late effects that occur in the days, weeks, and sometimes years, after treatment finishes, that eventually get better. Side effects can also occur as long-term effects that do not get better after treatment ends.
The treatment itself is painless, but it may cause side effects such as:
- skin reactions including red or darkening skin, soreness, itchiness, and blistering
- fatigue (tiredness)
- a change in eating habits (loss of appetite)
- feeling sick (nausea) and vomiting
- diarrhoea or constipation
- hair loss in the treatment area
- loss of interest in sex (loss of libido)
- difficulty getting an erection (erectile dysfunction)
There can also be either temporary or permanent damage to other body parts in the pelvic region like the bladder and reproductive organs, which may impact fertility.
Experiences of side effects with radiotherapy
For some patients radiotherapy was a painless and straightforward process: they experienced few if any side effects and none in the long term.
Stephen had radiotherapy for secondary cancer after surgery and although he had 30 sessions he had very few side effects.
Stephen had radiotherapy for secondary cancer after surgery and although he had 30 sessions he had very few side effects.
I then underwent surgery to remove the lump in December 2011 and then radiotherapy in February or March 2012.
but for this one they said it was, they thought that they could easily get this tumour remove it with surgery, and then give it quite a lot of radiotherapy so I went in December two thousand and eleven, for an operation to remove a tumour from the back of my knee, the surgeon thought he’d got it all and then in February 2012 I started 30 sessions of radiotherapy, obviously could, it’s on a kind of isolated limb, the doses of radiotherapy they can give are quite big compared to what they could give for example if it was next to a main organ. So they gave it a good zap of 30 sessions of radiotherapy I had which involved going to the hospital each day, an hour there, having the radiotherapy. It took about half an hour if they were on time, and then an hour back so we did that Monday to Friday every day for six weeks.
I did that, the symptoms of that were just my left leg started to get really stiff,
These are your side effects of the radiotherapy?
Yes it’s the side effects of the radiotherapy, my left leg started to get really stiff, ‘cos there were tumours in the back of my knee so it was obviously, that’s where your leg bends and as well the skin started to get quite sore around the area and as well I lost all the hair, so I had just a bald patch on my leg. It looked a bit weird.
For others, the side effects were considerable. One man describes burns (now a very unusual side effect from external radio therapy) caused by his radiotherapy and how he coped with them. Another explains how his side effects became more severe, and the recovery period longer with each treatment. He also hopes that the sexual dysfunction he has been experiencing will be temporary. A woman explains how she coped when her radiotherapy burned through to her vagina.
Describes the burns he developed from radiotherapy and how he dealt with them.
Describes the burns he developed from radiotherapy and how he dealt with them.
But towards the end of that of course it burnt all my skin off and I was raw and I was told when they said like you've had enough of that to go home, find an old bed sheet and make a poncho so you could hang it off your shoulders and not rub on your body.
And they gave me a lot of E45, a big tub of it and I used that. Well actually I went up the surgery and they, the nurse up there put it on the first day but I said "You let me have the stuff I'll put it on myself," so they let me have the stuff and I then put it on.
How long did it take for the burn to heal?
About three weeks, yeah about three weeks I think yeah.
Was it very painful?
Well I mean it was like lying in the sun and having heavy sunburn and all your skin falls off you know. It was yeah it was quite sore. It's all part of the treatment though isn't it really, yeah.
Describes how his side effects became progressively worse over the course of 6 sessions.
Describes how his side effects became progressively worse over the course of 6 sessions.
Early stages it was possibly within the first hour I was able to recover and even take a train back, but the third, fourth, fifth and sixth I think I was not able to drive my car and I had to depend on friends to take me down. And the recovery time of the fifth and the sixth were a few days and that was fairly daunting because I could not go anywhere close to food at all.
Yes the fifth session I did not know how it was going to affect me. That gave me a lot of anxiety over the final sessions. A friend of mine took me down and after the session I just collapsed in the car and I think I slept all the way back during the two hour drive back. But I recovered from that over a period of three days but I could not eat solid foods for about a week or so.
Sexually in terms of having an erection and stuff like that I think there is not permanent but near permanent damage.
Describes how radiotherapy burned her vagina and how she coped with this.
Describes how radiotherapy burned her vagina and how she coped with this.
Now I had the option to go and have some caps inserted to try and stretch it again but I've never ever bothered, I just thought I've gone through too much at this point in time, just leave it, so it's all been left on the wayside at the minute.
Oh God it was horrendous. Quite funny really, I used to like um, it was sort of quite nice, it was like May time and it was quite summery and that outside so I basically just sort of walked about with nice flowing skirts on you know and I think I um, I had a bit of cream.
Oh and I think they gave you something to actually flush up your vagina as well, I can't remember what it was called but I remember having to squish something you know up into the vagina which would help, probably relieve the burning sensation that was coming through you know.
For a number of patients, the side effects of radiotherapy were irreversible. One woman who was in her late 40s found that the treatment suddenly brought on menopause. Another man was left permanently impotent by radiotherapy.
Explains his feelings at having been left impotent by radiotherapy.
Explains his feelings at having been left impotent by radiotherapy.
And did they tell you that might happen?
No they didn't tell me this might happen no, no but you know they've said well it's just unfortunate.
Nobody mentioned it?
No. But they've given me, told me all sorts of things and of course I couldn't, remember when the dreaded viagra came out. I wasn't allowed to have that because I'd had a heart attack, of course. I wasn't allowed to go on it anyway not that I know whether it does any good or not but there are plenty of jokes about it.
And so what's your feeling about that?
Well I have I've always felt very bitter about that mm I'm being perfectly honest with you it has it's upset me a lot to think that but then again somebody said well after my cancer operation etc. etc. you've got, and when I was going to be fitted with a permanent colostomy, you take the choice between a bag and a box.
Many people felt strongly that patients were not being given adequate information about the possible consequences of radiotherapy. The woman whose menopause was brought on by the treatment felt that the same experience may have been much more traumatic for a younger person. Even people who had not suffered serious or lasting side effects felt they should have been better informed.
Maintains that people have the right to know about the possible side effects of radiotherapy.
Maintains that people have the right to know about the possible side effects of radiotherapy.
I've read about it since then. I've read quite a lot as time's gone on, and I've realised you know that I could have had more problems. It hasn't affected my sex life for instance which would have been a bitter pill to swallow. I mean I realise I'm very lucky that I haven't had any, any damage because obviously everything is so very close together down there. So, I've been very lucky.
Looking back, with the benefit of what you know now, do you think they should have told you about possible long-term damage from radiotherapy in the pelvic area?
Yes, I think they should have done. It wouldn't have made any difference to me, I still would have gone ahead with it. I was really convinced that that was the right treatment, it was giving me the best possible chance and so I would have gone along with it because I just wanted to live.
So I would have gone ahead with it but yes, I think, I think really you should be made aware of this. Yes, I think so. It, it may be that some people would be frightened and perhaps wouldn't want to go ahead with the radiotherapy and that would be an awful shame but I do think it, it is your right to know, to know these things, yes.
Several pointed out that knowing the risks would not have prevented them from having the treatment but would have helped them cope with the experience. The limited information they were given made things harder to deal with because they were inadequately prepared.
Being adequately informed about the possible consequences of radiotherapy has an impact on the patient's ability to participate in decision making about treatment. Radiotherapy was ruled out as a treatment in the case of one young woman because of the risk to fertility. A man who was given a choice between radiotherapy and surgery opted for surgery after being made aware of the risks by a radiotherapist. Another man whose cancer had been treated only with radiotherapy in the first instance had to live with chronic discomfort as a result of the treatment regretted having had radiotherapy when his cancer recurred and he had to have surgery anyway.
Wishes he'd had surgery rather than radiotherapy in the first instance.
Wishes he'd had surgery rather than radiotherapy in the first instance.
No, they didn't say anything like that. I saw an oncology doctor first and he said to me, he said "That my job really" he said "is to reduce the polyp so that, the surgeon can remove the, remove it properly you see". He said so by, by him using this, treatment it would reduce the polyp to a smaller size so it would be easier to take out. But then he said to me "I don't think you want the, the operation". I said "Well no, not if I can get away with just the x-ray treatment, I'll have that".
Which I thought after, after I'd had that treatment I was clear for three years, that it had completely gone. You see, if I'd have known that was gonna come back again I would, I would have had the operation immediately, rather than have the x-ray treatment. Ridiculous having the x-ray treatment if you've gotta have an operation afterwards.
So I thought well if I'd have had the operation first, it would have saved all that problem, most people that had this colostomy operation don't have this problem because they don't have the x-ray treatment, they just have the, have the, have the uh colostomy and uh, and they're more or less normal. They don't have any bottom trouble, even if they're sewn up below, they don't have it, it's the x-ray that done that see, that made it worse.
Internal radiotherapy
Internal radiotherapy is a radiotherapy that uses radioactive material, either in a solid form (this type is called brachytherapy) or in a liquid form administered orally or as an injection (this type is called radioisotope or radionuclide therapy).
A newer treatment being used for bowel cancer is high dose internal radiotherapy or high dose rate (HDR) brachytherapy. A tube containing radioactive material (the source) is inserted into the rectum and positioned close to or inside the tumour, typically while the patient is under a general anaesthetic. It is left in place for some time, typically an hour, to give the correct dose of treatment. As this treatment type is still relatively new, the possible risks and benefits of it as an option for treating bowel cancer are still being studied.
Last reviewed November 2024.
Last updated November 2024.
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