Bowel cancer is the fourth most common cancer in the UK and leads to around 16,800 deaths every year.
More than nine out of 10 cases of bowel cancer develop in older adults over the age of 50, and nearly six in 10 are in people aged 70 or older.
George Alagiah was first diagnosed with stage four (advanced) bowel cancer in 2014.
By the age of 66, it had spread to his lungs, liver, spine and lymph nodes.
Symptoms of bowel cancer
The three main symptoms of bowel cancer are having persistent blood in the stools, an ongoing change in bowel habit (such as needing to go more often or suffering the runs) and persistent lower abdominal pain, bloating or discomfort.
A loss of appetite may also occur, or somebody may suffer significant, unintentional weight loss.
Risk factors
Several things are known to increase the risk of bowel cancer, though they cannot explain every case.
These include a diet high in red or processed meats and low in fibre, being overweight or obese, not taking enough exercise and drinking too much alcohol.
Being a smoker and having a family history of the disease can also push up the risk.
Some people also have an increased risk of bowel cancer because they have another long-term condition, such as extensive ulcerative colitis or Crohn’s disease.
Detection
Bowel cancer screening is currently widely offered to people aged 60 to 74 who are sent a home stool kit every two years.
Those aged 75 and over can ask for a kit every two years by phoning the free bowel cancer screening helpline on 0800 707 60 60.
Bowel cancer can be very difficult to treat in its later stages.
But in the early stages, tumours can often be removed through surgery.
The main treatments for bowel cancer include chemotherapy, radiotherapy and targeted drugs, which depend on the genetic make-up of the tumour.
One in 15 men and one in 18 women will be diagnosed with bowel cancer during their lifetime.
Expert predictions are that 53,646 cases of bowel cancer (29,356 in men and 24,290 in women) will be diagnosed in the UK in 2035.