Colorectal (bowel) cancer: symptoms, tests and treatment

The NHS lists the symptoms below. Cancer Research UK notes that cancer in the colon and cancer in the back passage (rectal cancer) have similar symptoms. Bowel Cancer UK adds that not everyone has every symptom, that you may get different symptoms at different times, and that even one symptom is a reason to see a GP.

Many of these symptoms are very common and can be caused by other conditions, including piles, infections and inflammatory bowel disease. Having them does not definitely mean you have bowel cancer, but the NHS says it is important to get checked, because finding it 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 that you need to poo, even straight after going to the toilet.

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

• Losing weight without trying.

• Feeling very tired or short of breath, which are signs of anaemia that bowel cancer can cause.

Not necessarily. Cancer Research UK says blood in the poo is often due to other causes. Most often it comes from piles (haemorrhoids), especially if it is bright red, fresh blood. Bowel Cancer UK says bright red blood may also come from non-cancerous growths called polyps, and that it may be caused by bowel cancer.

Cancer Research UK explains that blood from higher up in the bowel does not look bright red. It goes dark red or black and can make poo look like tar. That can be a sign of cancer higher up the bowel, or of something else such as a bleeding stomach ulcer.

Either way, tell a GP about any bleeding. Cancer Research UK says your doctor will not think you are wasting their time.

For symptoms that are not sudden, the NHS advice is to see a GP. It says to try not to be embarrassed, because the doctor or nurse will be used to talking about these symptoms. Bowel Cancer UK suggests keeping a note of your symptoms, which can help you explain what you are experiencing.

The large bowel (large intestine) is the last part of the digestive tract. The upper part is the colon and the final section is the rectum. Cancer that starts in either area is grouped together as colorectal cancer, and in everyday UK usage it is called bowel cancer. Colon cancer and rectal cancer are the terms for where it started.

Bowel Cancer UK points out that bowel cancer can affect anyone, whatever their age, gender, ethnicity or where they live. The NHS explains that treatment depends partly on whether the cancer is in the colon, the rectum or both, which is why the distinction matters once tests have been done.

At a GP appointment the doctor will ask about your symptoms, general health, medical history and whether anyone in your family has had bowel cancer. Depending on your symptoms they may feel your tummy and ask to do a rectal examination, where a gloved finger is put inside your bottom to check for lumps. You can ask for a male or female doctor or nurse, and ask for someone else to be in the room.

You may be asked for a poo sample, or be given a home test kit called a faecal immunochemical test (FIT), to check whether you are bleeding from your bowel. You may also be asked to have a blood test. If the GP thinks your symptoms could be cancer you may get an urgent referral. The NHS stresses that this does not definitely mean you have cancer.

The main test in hospital is a colonoscopy. The NHS says it may be uncomfortable but should not be painful, and you will be offered a sedative and painkillers. A small sample of the bowel lining may be taken for testing (a biopsy). You may get some results the same day, or after a few days or weeks, and you can call the hospital or your GP if you are worried.

If you are told you have bowel cancer, you may need further tests, which can include a CT scan, MRI scan, PET scan, blood tests and genetic testing. The NHS says these show how far the cancer has spread and whether it has been caused by certain changes in your genes, which helps your specialist team decide on treatment.

Screening is offered to people who feel well, and is different from testing because of symptoms. The NHS says bowel screening uses a faecal immunochemical test (FIT) to look for blood in a sample of poo. You collect the sample at home and post it to a laboratory; postage is free. It can help find cancer early, before you have symptoms, which may mean it is easier to treat.

The NHS says screening is currently offered to people aged 50 to 74 every 2 years. If you are registered with a GP, you automatically get a kit through the post. People aged 75 or over can ask for a test. It is your choice whether to have screening.

You usually get the result by letter within 2 weeks. Most people have a result saying no further tests are needed, which means no blood was found. The NHS stresses that this does not always mean you do not have bowel cancer, so you should still know the symptoms. If blood is found you are invited to an appointment with a specialist nurse, and will usually need a colonoscopy. The NHS adds that blood in your poo does not always mean cancer: an anal fissure or bowel polyps are more common and less serious causes.

The NHS says treatment depends on the size of the cancer, whether it is in the colon, rectum or both, whether it has spread, whether it has certain genetic changes, and your age and general health. You may be offered a combination of treatments. Your specialist team will explain the benefits and side effects, make a treatment plan with you and help you manage side effects.

The NHS says that if it is bowel cancer, finding it early can make it easier to treat. If it has been diagnosed at an advanced stage, it may be hard to treat and not possible to cure. In that case the aim of treatment is to slow the growth and spread of the cancer, help with symptoms and help you live longer.

You would be referred to a symptom control team or palliative care team, who help manage symptoms and can also help you and your loved ones get other support. The NHS recognises that hearing the cancer cannot be cured can be very hard news to take in.

It is not always known what causes bowel cancer. The NHS says it can be caused by genetic changes, lifestyle and environmental factors, and that certain health conditions can also make you more likely to get it.

The NHS says you cannot always prevent bowel cancer, but there are things that lower your chance of getting it. None of these replaces screening or the need to report symptoms.

• Eat a healthy diet including at least 5 portions of fruit and vegetables a day.

• Stay active and exercise regularly.

• Lose weight if you are overweight.

• Quit smoking.

• Drink less alcohol.

• Eat less red and processed meat.

The NHS says a team of specialists will help you through diagnosis and treatment. The team includes a clinical nurse specialist, who is your main point of contact during and after treatment and can answer questions. The NHS also points to Bowel Cancer UK, Macmillan Cancer Support, Cancer Research UK and Marie Curie for information and support.

Most bowel cancer care in the UK starts with a GP and, if needed, an urgent referral on the NHS, followed by tests and a specialist team. The home screening test is an NHS programme.

Some people also see a private colorectal specialist or have a colonoscopy privately. If you do, it is reasonable to ask who will be responsible for your treatment plan, whether your results will be discussed by a specialist team, and how follow-up will be coordinated with your GP.