Callum Stroud, 29, from Kent, will be taking part in this year’s Royal Parks Half Marathon to raise money for Macmillan Cancer Support, three years after being diagnosed with Acute Lymphoblastic Leukemia (ALL) and told by doctors he had just three days to live. 

Callum, who now resides in North London, was diagnosed in August 2022 at just 26 years old. Before his diagnosis, he had been feeling unwell for a month but never expected anything so serious at such a young age. When the diagnosis came, doctors warned him he might only have days left without urgent treatment. He recalls, “Getting the news that you might not be here in a matter of days was terrifying to say the least, and a moment which I still have flashbacks about even now”.

Callum was rushed to University College Hospital London (UCLH), where he started immediate treatment at their specialist blood cancer centre. What followed was a gruelling battle involving months of chemotherapy and immunotherapy, two devastating relapses in 2023, before being approved for Car-T Cell Therapy in March 2024. 

Since July 2024, Callum has been on a maintenance programme that includes daily chemotherapy in tablet form, intravenous chemotherapy and intrathecal chemotherapy (chemotherapy injected directly into the spinal fluid) which he has every six weeks. He is expected to remain on this treatment for another two years, meaning his cancer journey could last five years in total. 

Reflecting on the experience, Callum says: “This whole process has been agonising, especially experiencing it in your 20s where you’re supposed to be at the peak of your health, and planning your life ahead of you. All of those plans go out of the window. Somehow you have to find a way to navigate everything, whilst still trying to live your life and pay your bills.”

During his treatment, Callum had to leave his physically demanding engineering career. After eight months off work, he retrained in marketing and now works for Publicis Groupe, thanks to their ‘Working with Cancer’ policy that supports employees with serious illnesses. 

In early 2025, Callum saw an advert on the tube for the Royal Parks Half Marathon and decided to take on the challenge as a way to push himself and regain focus. He explains: “It’s been challenging training whilst still receiving treatment, but I’ve found it gives me a lot of benefits mentally and physically to deal with my situation. My younger brother ran the London Marathon while I was receiving Car-T Therapy, and that gave me some inspiration to take on the half marathon. 

Speaking about race day, Callum says “I’m excited – it’s my first race so I’m looking forward to the experience and atmosphere. A lot of people have called me crazy for doing this race, even my consultant said he’s never seen someone at my stage of treatment do something like this. In my crazy mind this only made me want to achieve this goal even more!”.

Asked what message he hopes to share, Callum says: “I want to prove to myself and others that just because you are going through difficulties in life, it doesn’t have to define who you are and what you’re capable of. I hope to inspire people who are struggling to not give up and to keep fighting.”

Callum is running for Macmillan Cancer Support, who have been by his side throughout his three-year journey, providing support groups, emotional guidance and funding vital research into new treatments.

To donate to Callum’s cause, please visit his fundraising page

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