‘I haven't been treated at the Máxima Center myself, but it feels special to work here.’
As a teenager, Leron Kok (now 28) was diagnosed with a rare form of leukemia. Today, he works as a PhD student at the Princess Máxima Center, where he conducts research into childhood cancer. His own experiences have strongly shaped these choices.
An interest in science grew stronger
Leron says: “As a child, I already had a strong interest in science and biology. My life changed quickly in 2011, when I suddenly developed large bruises. After visiting my GP, I was admitted that same evening to the University Medical Center Groningen (UMCG) with a diagnosis of leukemia. I was thirteen.
During my first week at UMCG, it became clear that I had a rare type of leukemia: Acute Promyelocytic Leukemia (APL). In principle, this type was treatable. I received chemotherapy at UMCG, followed by chemotherapy pills at home. There was a chance the disease could return after two years, but even then it would still be treatable.”
“After six months, a routine bone marrow puncture showed that the leukemia had returned—much sooner than expected. A lumbar puncture revealed that the leukemia had also spread to my cerebrospinal fluid. Suddenly, I found myself in a much more intensive treatment trajectory. For example, I had to go to the hospital fifty days in a row to receive intravenous anti-cancer medication.”
From chemotherapy to a stem cell transplant
“Because the leukemia returned so quickly and aggressively, I also had to undergo a stem cell transplant. A donor was needed—and fortunately, one was found. I was fourteen when I received the transplant. It was an intense time.”
“During my treatment, my interest in cancer research grew. In secondary school, I consciously chose science-focused subjects to prepare for studying in this field.
After completing my bachelor’s degree in Liberal Arts in Enschede, I moved to Wageningen, where I pursued two master’s degrees in Molecular Life Sciences and Bioinformatics.”
The Máxima Center made an impression
“During my master’s, I did an internship at the Máxima Center. I was impressed by the center. I would have liked to stay, but that wasn’t immediately possible at the time.
In 2022, I was able to start as a bioinformatician in a preclinical research group. A year later, I began my PhD in the research group of Sebastiaan van Heesch.”
“In our research, we analyze the role of a new (previously unknown) group of small proteins, also known as ‘microproteins,’ in childhood cancer. We study whether they play a role in cancer and whether we can use them for new treatments, such as immunotherapy.”
“I wasn’t treated at the Máxima Center myself, but it feels special to work here. There is a lot of attention for children and their parents, as well as for children’s development alongside treatment. Think of an on-site school, psychological support, but also spaces for making music and a teen lounge. During my own treatment, I missed that. I was often in isolation and had little contact with peers. I noticed that later, for example in secondary school.”
Some things remain challenging
“It was sometimes difficult to connect with others. I noticed that during my student years as well. Because of the treatment, I get tired more quickly. I have scar tissue in my lungs and other lasting effects. So I have to make choices about what I can and cannot do.”
“Fortunately, I can still exercise. I go bouldering and mountain biking. That helps me stay fit. In 2025, I participated in Alpe d’HuZes. Together with colleagues from the Máxima Center, I cycled up the mountain three times. That was literally and figuratively a highlight for me.”
Hobbies
“To unwind from work, I enjoy cycling to the station in Bunnik with the wind in my hair, and then taking the train home. I like meeting up with my group of friends—many of whom I met through student scouting in Wageningen—for activities like board games or Dungeons & Dragons. I also enjoy working with my hands instead of my head, for example by doing woodworking with a laser cutter.”
“Another special moment was just before my job interview at the Máxima Center. In the lobby, I ran into my former oncologist from UMCG. Despite my face mask, she recognized me immediately. That shows how involved doctors are. I find it special that we are now both contributing to the same goal, each in our own role.”
‘I want to continue growing here’
“I’ve now been working here as a PhD student for two and a half years. A PhD takes four years. In about a year and a half, I hope to continue as a researcher. I want to keep contributing to research that helps children. That is my main motivation.”
Lees ook:
- ‘I’ve rediscovered my identity and learned what I’m still capable of.’Cherine (35) was 10 years old when she was diagnosed with bone cancer. She had to choose between several intensive treatments: a year of chemotherapy in the United States in the hope of saving her leg, amputation, rotationplasty, or removal of her knee and thigh muscles. She chose the latter. Now she visits the LATER outpatient clinic at the Máxima and works there as well.
- ‘Sometimes I try to explain to my classmates how I feel, but they don’t understand the pain.’Froukje (15) was two years old when she was diagnosed with leukemia. Although that was a long time ago, she now feels more than ever how her illness still affects her. She doesn’t always feel understood. Together with her mother, she shares her story.
- ‘I am no longer sick, but I still experience the effects of the treatment. It continues to haunt you.’Mandy (25) was 15 when she was diagnosed with Hodgkin lymphoma. She underwent a year-long treatment before she ringed the bell. The cancer is gone, but the effects of the chemotherapy are not. Mandy visits the LATER clinic at the Máxima Center once a year and, ten years after her diagnosis, is almost graduating as an oncology nurse.