Surgery for rectal cancer
There is a risk of problems or complications after any operation. Your surgeon will go through the benefits and risks of the operation before you sign the . We are unable to list all the possible problems after surgery on this page.
Leaks can happen where the surgeon joins the ends of your colon together. This is called an anastomotic leak. This is a serious problem and you need to have treatment straight away.
Treatment includes:
stopping eating and drinking
antibiotics
a drain
usually another operation
You might need more surgery to repair the leak if other treatments don’t work. This operation will usually involve you needing a stoma.
Your bowel might be slow to start working after surgery. This is called an ileus.
Treatment includes:
stopping eating and drinking and having fluids through a drip
a tube down your nose into your stomach (nasogastric tube) to drain bile and stop you feeling sick
This usually gets better with time. But some people need more surgery if there is a blockage in the bowel. It is very rare to develop a blockage very soon after a bowel cancer operation.
You might have problems with your stoma if you have one.
Your specialist stoma nurse will go through any possible problems and what can help.
Possible problems include:
skin irritation around the stoma
stoma leakage
passing lots of poo through the stoma – which could mean you become dehydrated
Things that can help include:
barrier films for the area around the stoma
making sure you have the right bags and stoma equipment - your stoma nurse will help with this
drinking well to make sure you stay hydrated
Get more information about living with a stoma
After any major operation there is a risk of:
You are at risk of getting an infection after an operation. This includes a wound, chest or urine infection. Symptoms can depend on where the infection is. Tell your doctor or nurse if you have any symptoms of infection.
These include:
a high temperature
shivering
feeling hot and cold
feeling generally unwell
cough
feeling sick
swelling or redness around your wound and your wound might feel hot
a strong smell or liquid oozing from your wound
loss of appetite
cloudy smelly pee
If you get an infection, your doctor gives you antibiotics to treat it.
Sometimes for an infection in your wound, you may need another operation. But this is rare.
Blood clots are also called a deep vein thrombosis or DVT. They are a possible complication of having surgery because you might not move about as much as usual. Clots can block the normal flow of blood through the veins. Let your doctor or nurse know if you have an area in your leg that is swollen, hot, red or sore.
There is a risk that a blood clot can become loose and travel through the bloodstream to the lungs. This causes a blockage called a pulmonary embolism. Symptoms include:
shortness of breath
chest pain
coughing up blood
feeling dizzy or lightheaded
To prevent clots it's important to do the leg exercises that your nurse or taught you. And to move around as much as possible. Your nurse might also give you an injection just under the skin to help lower the risk whilst you are in hospital. You might need to carry on having these injections for a few weeks, even after you go home. This depends on the type of operation you had.
Your nurse might teach you to do these injections yourself before you go home. They will make sure you are comfortable doing them. Or a district nurse might come to your home to do them.
It's important to continue wearing your anti embolism stockings if you have been told to by your doctor.
There is a risk that you will bleed after your operation. The team looking after you will monitor you closely for signs of bleeding. The treatment you need depends on what is causing the bleeding and how much blood you lose. You might need a blood transfusion.
You will need time to get over surgery before having sex again. Give yourself at least six weeks after major surgery.
The effects mentioned below don't affect everyone who has bowel cancer treatment. Some of the problems may get better over time. But some changes can be permanent. You may feel very embarrassed to talk to doctors or nurses about sexual problems. But if you tell them about any problems you have, they can find ways of helping you to deal with them.
An operation involving the rectum can affect the nerves to the sex organs. A man may not be able to get, or keep, an erection, or might have problems with orgasm and ejaculation. This includes retrograde ejaculation. This means that when you ejaculate, your semen and sperm go back into your bladder instead of coming out of your penis. Retrograde ejaculation is not dangerous or harmful. And it will not stop you having an orgasm. But your orgasm will feel different because it will be dry.
Women might also notice changes. These can include vaginal dryness, pain during sex or vaginal narrowing.
You may have surgery for cancer in your lower rectum, to remove your anus and rectum. If you're used to having anal sex, you will no longer be able to. Your surgeon and specialist nurse will talk to you about this before and after your surgery. Sharing your thoughts and feelings with your partner can help with this.
Read more about your sex life after bowel cancer treatment
After surgery you might notice changes to your bowels including:
pooing more often
having little or no warning that you need to poo or pass wind
changes to your poo such as loose runny poo (diarrhoea) or hard, difficult to pass poo (constipation)
feeling bloated and passing wind
difficulty emptying your bowel completely when you poo
After rectal cancer surgery
Most people have problems with their bowel function for several weeks after rectal cancer surgery, and for many, these problems can continue for around a year. Although it is unlikely that your bowel habits will return to how they were before surgery, these problems should become less severe with time. Your specialist nurse or doctor can advise you about what you can do to manage these changes.
Find out more about bowel changes after bowel cancer treatment
Last reviewed: 01 Apr 2025
Next review due: 01 Apr 2028
The type of surgery you have for cancer of the back passage (rectum) depends on the position and the size of your cancer.
Living with bowel (colorectal) cancer may mean you have changes to your diet, sex life or body image. There is support to help you cope.
You might have a colostomy or ileostomy after surgery for bowel cancer. The end of your bowel is brought out into an opening on your tummy. The opening is called a stoma or ostomy.
Treatment depends on whether you have colon or rectal cancer, as well as your cancer stage. You might have surgery, radiotherapy or chemotherapy or a combination of these.
Bowel cancer means cancer that starts in the colon (large bowel) or back passage (rectum). It is also known as colorectal cancer.

About Cancer generously supported by Dangoor Education since 2010. Learn more about Dangoor Education
What to ask your doctor about clinical trials.
Meet and chat to other cancer people affected by cancer.
Questions about cancer? Call freephone 0808 800 40 40 from 9 to 5 - Monday to Friday. Alternatively, you can email us.