Rectal cancer: symptoms, tests, treatment and what happens next

The NHS lists the main symptoms of bowel cancer, which apply to cancer of the rectum. Macmillan says symptoms of rectal cancer can include blood in your poo, bleeding from the back passage and a change in your normal bowel habit.

Having these symptoms does not definitely mean you have bowel cancer. The NHS stresses that some of the symptoms are very common and can be caused by other conditions, but it is important to get checked by a GP, because finding cancer early can make it easier to treat.

• Changes in your poo, such as softer poo, diarrhoea or constipation that is not usual for you.

• Needing to poo more or less often than is usual for you.

• Blood in your poo, which may look red or black, or bleeding from your bottom.

• Often feeling like you need to poo, even if you have just been to the toilet.

• Tummy pain, a lump in your tummy or bloating.

• Losing weight without trying to.

• Feeling very tired or short of breath, which can be signs of anaemia.

The NHS says to see a GP if you have any symptoms of bowel cancer and to try not to be embarrassed, because the doctor or nurse will be used to talking about them. Ask for an urgent GP appointment or get help from NHS 111 if your poo is black or dark red or you have bloody diarrhoea.

Call 999 or go to A&E if you are bleeding non-stop from your bottom, or there is a lot of blood or you see large blood clots when you poo. The NHS says not to drive yourself to A&E.

The rectum is the back passage, part of the large bowel, which is made up of the colon, rectum and anus. Macmillan says cancer that starts in the colon or rectum may be called bowel cancer or colorectal cancer. Rectal cancer is the part of bowel cancer that starts at the end of the large bowel.

Macmillan says bowel cancer is more common in older people, but the number of younger people aged 50 and under diagnosed with it is increasing.

The NHS says treatment depends on the size of the cancer, whether it is in the colon or rectum, whether it has spread, whether it has certain genetic changes, and your age and general health. You may be offered a combination of surgery, chemotherapy, radiotherapy and targeted medicines. A team of specialists, called a multidisciplinary team, plans the treatment (Macmillan).

Macmillan says surgery is the most common treatment for rectal cancer, the type depending on the stage and where the cancer is in the rectum. Very early-stage cancers can sometimes be removed through the anus; others are removed by open or keyhole surgery. Some people need a temporary, or sometimes permanent, stoma. Most people have changes in how their bowel works after surgery, and these usually improve over time.

You usually begin by seeing your GP, who will ask about your symptoms, health and family history, and may feel your tummy and do a rectal examination with a gloved finger. The NHS says you may be asked for a stool sample or given a faecal immunochemical test (FIT) kit, which checks whether you are bleeding from your bowel, and may have a blood test.

If the GP thinks your symptoms could be cancer, they will refer you to a specialist. The NHS says the main test for bowel cancer is a colonoscopy, where a thin flexible tube with a camera looks inside the bowel and a small sample (biopsy) may be taken. Macmillan says you might instead have a sigmoidoscopy, which examines the inside of the rectum.

If cancer is found, the NHS says you may have a CT scan, MRI scan, PET scan, blood tests or genetic testing to show how far it has spread. This staging helps your team decide on treatment. Macmillan also notes that some people are diagnosed through the NHS Bowel Screening Programme.

It is not always known what causes bowel cancer, but the NHS says it can be caused by genetic changes, lifestyle and environmental factors, and that certain health conditions can make you more likely to get it. Macmillan says having one or more risk factors does not mean you will definitely get it, and some people without risk factors do.

• Being over 50.

• Smoking and being overweight.

• A close relative who has had bowel cancer.

• Inflammatory bowel disease (Crohn's disease or ulcerative colitis).

• Bowel polyps.

• Lynch syndrome or familial adenomatous polyposis (FAP).

The NHS says you cannot always prevent bowel cancer, but you can lower your chance by eating a healthy diet with at least 5 portions of fruit and vegetables a day, staying active, losing weight if you are overweight, quitting smoking, drinking less alcohol and eating less red and processed meat.

Macmillan says you will have regular check-ups during and after treatment, usually continuing up to 5 years, which may include blood tests, MRI or CT scans, and colonoscopies or sigmoidoscopies. Tell your doctor or specialist nurse as soon as possible about new symptoms between appointments.

Rectal cancer and its treatment can affect your sex life, body image and fertility, and Macmillan says changes may improve over time, but sometimes they are permanent. The NHS says a clinical nurse specialist is your main point of contact, and Macmillan has a free helpline on 0808 808 00 00.

On the NHS, rectal cancer is usually suspected through a GP visit or bowel screening and investigated by a colorectal team, with treatment planned by a multidisciplinary team. Some people pay for a private appointment or colonoscopy for speed, but treatment decisions and ongoing follow-up are generally coordinated through the cancer team, so results should be shared with your GP.