Marco Choi, a 28-year-old from Chelmsford, Essex, has been declared in remission after being diagnosed with blood cancer at 25 that later progressed to stage 4 when doctors found a tumour in his brain. He describes himself as the "luckiest unlucky" person. Choi, now a Blood Cancer UK ambassador, had been experiencing headaches, muscle aches and cold sweats from November 2023, which he initially attributed to his gym routine.
He also noticed blood in his stool but mistook it for a side effect of iron supplements, which can darken stool. However, after collapsing at work on December 13, 2023, he was rushed to hospital. By January 2024, he was diagnosed with diffuse large B-cell lymphoma (DLBCL), an aggressive blood cancer affecting white blood cells, most common in people in their 60s and 70s.
From All-Clear to Relapse
Choi underwent six cycles of chemotherapy and received the "all-clear" by the end of July 2024, which he described as "amazing." But a month later, he had a seizure and doctors discovered a tumour in his brain. He was diagnosed with secondary central nervous system (CNS) lymphoma, a "particularly aggressive and difficult-to-treat form of blood cancer where fewer than half of people survive," according to Heidi Smith, a nurse at Blood Cancer UK.
His treatment included more chemotherapy, radiotherapy, and an autologous stem cell harvest and transplant, using his own stem cells to replace blood cells destroyed by high-dose chemotherapy. By mid-June 2025, Choi finished treatment, and in August 2025, he was told he was in remission. He told PA Real Life: "I felt amazing when I got told that. The first time I beat it, I thought it was all over and that was short-lived (but) this time, we laughed about it and said that it's really over now."
Symptoms and Diagnosis
In the months before his diagnosis, Choi was going to the gym "three to five times" a week and took supplements like iron tablets and creatine, but also drank "three to five times" a week. He said he was "partying a lot and making the most of my younger years." When symptoms began in November 2023, he did not think it was serious. On December 13, he collapsed at work, losing consciousness while taking an order at a takeaway shop.
He was taken to Broomfield Hospital in Chelmsford, where doctors found internal bleeding causing blood in his stools, requiring 11 blood transfusions. Discharged on December 23, doctors discovered a mass in his chest, leading to CT and PET scans. On January 25, 2024, he was diagnosed with DLBCL. He recalled: "When they told me I had cancer, it just felt surreal... And it didn't really hit me until I was on the bus back from the hospital and I had to tell my mum."
Treatment and Recovery
From February 5, 2024, Choi had six rounds of intense chemotherapy, experiencing gut issues, hair loss, difficulty sleeping, nausea, and extreme breathlessness. He got the all-clear on July 29, 2024, and celebrated at Nobu in London. However, on August 28, he had a seizure at the gym, leading to an MRI that confirmed a brain tumour. His care transferred to University College London Hospitals (UCLH), where he started chemotherapy again, had a stem cell transplant, and 20 sessions of radiotherapy.
He also had a brain biopsy on December 23, 2024, after another seizure, where a consultant remarked he "might not see" 2025. He finished treatment on June 17, 2025, and was told he was in remission in August. Choi thanked his mother Helen, 61, his older brother and sister, friends, and medical staff for support. He said: "My perspective really changed... I wanted to repay all the kindness that I received... So that's why I wanted to be an ambassador (for Blood Cancer UK)."
Raising Awareness
Heidi Smith said: "Marco's story shows just how devastating and unpredictable blood cancer can be, even for someone in their 20s. It's wonderful to hear that Marco is now back in remission after everything he's been through, but sadly not everyone has the same outcome." She highlighted the need for better treatment options, referencing Blood Cancer UK's £25 million Trial Treat Beat appeal to double survival chances for the deadliest blood cancers.
Choi is sharing his story because he noticed a "lack of diversity" in a blood cancer booklet he received. He said: "It didn't really reflect me. I'm young, I'm active, I thought I was relatively healthy and I'm Asian, but I just saw white men who were older. Even the doctors made a joke that when they saw I was 26 on the file, they thought they read it wrong and I was 62. So I want to show that anyone can get (blood cancer)." He is supporting Trial Treat Beat, with more information available on Blood Cancer UK's website.
