Today, more than 8 in 10 children and young people in the UK, aged 0 to 24, survive their cancer for 10 years or more.
Survival of children and young people has hugely increased over the last 50 years. In fact, progress we’ve made in treating and diagnosing these cancers means that we have avoided almost 30,000 deaths from children’s and young people’s cancers since the 1970s.
While there have been enormous strides in survival, new challenges have emerged in treating children’s cancers.
“It’s really only recently, I suppose that you could say, that we’ve had the luxury of worrying about this,” explains Dr Debbie Hicks, a Newcastle University Research Fellow.
“We now have about 75-80% of all childhood cancer patients surviving their cancers. That’s wonderful, of course. But we now have this large population of patients that we didn’t before, and they have significant unmet needs.”
Hicks is referring to what we call ‘survivorship’. The term encompasses what it means to live beyond cancer. For many, this involves living with the long-term side effects of cancer treatment.
We spoke to Hicks about her work in the field, and what is being done to understand and minimise the impact of long-term side effects. We also spoke to Charlie, who had a brain tumour as a child, about what improving survivorship means to him.
What does survivorship mean?
“Survivorship is a really broad topic, and encompasses lots of different things,” explains Hicks.
“There are variations in the definition, and it survivorship encompasses living with, through, and beyond a cancer diagnosis. Many survivors are burdened by negative health consequences as a result of their cancer itself and the treatment they’ve been given. But it’s more than that. It’s the overall quality of life, the emotional impact and the overall burden of having cancer as a child.”
Hicks’ research focuses specifically on medulloblastoma, the most common malignant brain tumour in children and one that affects approximately 55 children each year in the UK.
The side effects of medulloblastoma treatment that present later into a child’s life, otherwise known as the ‘late effect profile’, can be hard to predict.
“But predominantly,” explains Hicks, “the combination of brain surgery, cerebral spinal radiation (whole brain and spinal cord radiotherapy) and chemotherapy often given to medulloblastoma patients, often results in frequent problems that affects the quality of survival after medulloblastoma diagnosis.”.
Cognitive effects, such as problems with memory, thinking, attention, and learning difficulties are common in children who have been treated for medulloblastoma, but a whole host of other problems are seen too, including hormone dysfunction, heart problems and sensory impairments such as hearing loss. Medulloblastoma survivors are also at higher risk of second cancers.
Hicks is researching the link between medulloblastoma, its treatment and late-effect profile to understand its complexity and underpinnings, and to develop strategies for improved quality of life for survivors going forward. Her goal is to make sure that young people with medulloblastoma can grow up with minimal late effects.
Charlie Williams, from Suffolk, was diagnosed with medulloblastoma when he was 5 years old.
“To treat his cancer Charlie had a 7 hour operation, 5 weeks of radiotherapy and a year of chemotherapy.”
Now 23, Charlie tells us what it’s like to live with some of the side effects of his treatment.
“When I was treated, the radiotherapy damaged my spinal cord and affected my hormones,” he explains. “My parents are tall and I was always one of the tallest in the class when I was younger. When I had the radiotherapy, the doctors said that, without growth hormones, I would have stayed the same height as I was then. “
He explains that his growth was one of the main side-effects at the time of his treatment. However further down the line, following his recovery, Charlie’s hearing was impacted.
“After a hearing test in 2008 (shortly after I started middle school) audiologists concluded that I had lost the high decibel of my hearing in one ear. This resulted in the use of a hearing aid. 18 months later I had lost it in the other ear,” Charlie explains.
Charlie wasn’t happy wearing hearing aids at the time, but it’s something he’s adapted to over time. “People had to say things 2 or 3 times and sometimes shout before I could hear them. The hearing aids I wear now are very discreet and the technology of them has advanced so much, they’re very subtle.”
“I do think the side-effects feel mild in comparison to what I faced.” After his treatment, Charlie had to re-learn everyday tasks, such as walking and eating.
“As a result of the treatment I have a low immune system (which I take tablets daily for) and I also have a few scars. I don’t think people who meet me now would know that I was any different to any other 23-year-old.
“I have check-ups each year which have shown I have kept stable. I had those at the children’s ward until I was 17 but now have them in an endocrine area which goes to show how far I’ve come. I always go with my mum, and I think that, even though you might look at us and think we are both calm, there are so many things going through our minds – you can’t avoid the “what if” thoughts.
“I know how hard the experience was for all my family, and I am now keen to support Cancer Research UK as this research is so important to helping develop new, kinder treatments for the future.”
Unpicking the long term side effects
Hicks’ research is focussing on what is termed ‘molecular survivorship’. This area of work zooms in on the interaction between our own human biology and the cancer treatment and tumour itself.
“So for example, when you radiate, you’re not just a radiating the tumour itself, although we’re getting better at being more precise, but there’s some normal tissue that also receives radiation. And the specific genetic makeup of a patient can hugely influence how well it’s tolerated in normal tissue.”
So as Hicks describes, her team is looking at how the molecular makeup of the individual who has the tumour, rather than the tumour itself, can influence someone’s late effect profile. “So say we have two kids who receive the same treatment for medulloblastoma, but have a different quality of life afterwards.
“My interest is how do the genetics and molecular features of the host (patient) determine long term side-effects”
The team is exploring whether knowing in advance if someone is predisposed to more severe late effects could modify or reduce the intensity of the treatment needed. Equally, if the treatments couldn’t be altered, how could the child be monitored to ensure the correct interventions could manage the side effects.
Time to address this unmet need
There are a number of challenges when it comes to studying this area of survivorship. As the concept of survivorship, particularly for children’s cancer, is quite new, there are a lack of historic samples to work with.
We’ve written before about the importance of samples in understanding children’s cancer, but this is quite a different problem.
“The resources that we have to work with are coming from old collections from patients,” says Hicks. “As this was much less of an issue, the majority of samples are from the tumour itself, but we have very little genetic information about the person who the tumour belonged to.” Fortunately, this is now changing, as the importance of also interrogating host biology is being recognised.
Despite the challenges, Hicks is determined to continue working in this area and feels close to the cause. “Childhood cancer survivorship is a really nuanced place,” she says. “Because, of course, kids surviving their cancer is extremely positive, and that’s to be celebrated. But we can now do better for these children, by developing kinder treatments and bringing cancer survivorship into our sharp focus for attention and action in the coming years”.
Debbie Hicks is a Fellow of Molecular Cancer Survivorship at Newcastle University. She graduated with Honours in Molecular Biology before carrying out a PhD in the molecular genetics of rare disease. Debbie’s research involves elucidating the biological features important in the development and progression of medulloblastoma and deriving novel biomarker-driven risk-stratification models that work towards the application of kinder, precision, therapies.
Her work aims to reduce the disease/treatment-associated burden in medulloblastoma survivors by understanding the biological underpinnings of late effects, and advancing drug strategies for the amelioration of late effects in medulloblastoma survivors.