It is the third biggest killer among cancers, claiming 15,000 lives a year. That's more than breast cancer and prostate cancer, according to charity Bloodwise.
There are more than 100 forms of the disease - which can mean multiple visits to the GP before it gets spotted.
Thirty six per cent of people have to see their GP three or more times before getting a diagnosis that could save their life, while 14 per cent of patients had to see their GP five or more times - compared to eight per cent average for cancer patients overall.
Paramedic Derek Loutitt was only diagnosed after he began coughing up blood and had to be rushed to hospital.
He said: "It wasn't until after my third visit to the GP that my condition was diagnosed. I'd been before because the GP thought I had urinary infection and I was sent away with antibiotics.
"Eventually, my GP realised the seriousness of the situation and called an ambulance.
Paramedic Derek was only diagnosed after he began coughing up blood. Credit: Bloodwise
"I'm an NHS paramedic and it was one of my own ambulances that took me on a blue light from the GP surgery to the hospital, where after blood tests and other checks I was told I had acute myeloid leukaemia."
He added: "If I hadn't been diagnosed when I was, I might not have made it beyond six weeks. Surviving should not be down to luck.""
To mark World Cancer Day Bloodwise is calling on the NHS to back its pledge to make sure that 75 per cent of cancers are diagnosed at stages one or two, to give patients the best chance of survival.
Sky Sports presenter Simon Thomas became a president of Bloodwise when his wife, Gemma, died three days after she was diagnosed with acute myeloid leukaemia in 2017.
In a post to Twitter backing the campaign, the former Blue Peter presenter said his wife had visited her doctor three times before eventually receiving her diagnosis - and urged more people to get checked out.
He wrote: "It's #WorldCancerDay & @bloodwise_uk are raising awareness for the 1000's with blood cancer who repeatedly visit their GP before a diagnosis. For my wife Gemma it was 3X & still wasn't spotted. This needs to change. Please share your number & tag @bloodwise_uk #Bloodwise"
Dr Alasdair Rankin, Director of Research and Patient Experience at Bloodwise, said: "Patients and GPs can easily put the symptoms of blood cancers down to the ageing process or harmless conditions.
"It's vital that GPs are made aware of the signs that could indicate blood cancers and that patients are reassured that it's OK to keep seeking help if they continue to experience unusual, ongoing or unexplained symptoms."
And though many of the symptoms may be nothing serious, it's important not to ignore them.
The most common signs of blood cancer are;
Lumps or swells
Bone or joint pain
Extreme tiredness (fatigue)
Unexplained weight loss
Bruising or bleeding easily
Drenching night sweats
For ore information, visit https://bloodwise.org.uk/
Featured Image Credit: PA