Survivors of childhood cancer are known to be at higher risk for physical health problems later on, but whether or not (or how much) an early cancer diagnosis affects their mental health risks later on is not so clear. That's according to Paul C. Nathan, MD, MSc, FRCPC, a clinician investigator, staff oncologist, and Director of the Aftercare Program in the Division of Haematology/Oncology at The Hospital for Sick Children in Toronto, who recently investigated the question with his colleagues (Cancer 2018: doi:10.1002/cncr.31279).
"A lot of the risk factors were the same things we see in the general population," Nathan told Oncology Times. "The problem is that we tended to see these problems more frequently in childhood cancer survivors."
The researchers looked at the medical records of 4,117 5-year survivors of childhood cancer treated in any of the five pediatric cancer centers in Ontario, Canada, between 1987 and 2008. Everyone was diagnosed and treated before they were 18. The study cohort also included a control group of 20,269 healthy individuals matched for age, gender, and where they grew up geographically. (Because Canada has a publicly funded health care system, information about medical diagnoses, cancer treatments, and health care visits are available from cancer registries and administrative databases.)
The data showed that the childhood cancer survivors had a 34 percent increased risk for a medical visit for a mental health complaint than the general population. More than 40 percent of the survivors in the group studied had at least one visit for a mental health complaint. And the cancer survivors had a 13 percent increased risk for a severe mental health event, which included emergency room visits or hospitalizations due to a mental health complaint or problem. And childhood cancer survivors who were treated at the youngest ages (between 0 and 4 years) were at the highest risk for these severe mental health events.
Nathan said he and his colleagues were not surprised by the findings, as some previous evidence and their own clinical experience suggested they would find these elevated rates of mental health problems in survivors of childhood cancer. But, he added that the findings point to some very important implications. Here's what else he told Oncology Times.
1 There's a lot of research when it comes to survivors of childhood cancer-what's new about the question you asked and what you found?
"I think much of the focus in some of the survivor outcomes has been on the long-term physical consequences of cancer therapy. We know survivors have an elevated risk for chronic health conditions, such as cardiac disease, new cancers, and endocrine problems. There has been some work in mental health and psychological outcomes, but there's definitely been far less of a focus on that than there has been on the physical manifestations and the physical consequences of therapy.
"This study adds to the small, but growing, body of literature that [shows] surviving childhood cancer can impact long-term emotional and psychological health. And [it suggests] that risk-based care for cancer survivors-which considers previous cancer diagnoses, treatments received, and physical consequences-has to focus on mental health consequences as well."
2 Your data found one of the groups at the highest risk for mental health problems later on were survivors of childhood cancers who were treated at the youngest ages. Do you any suspicions why that group was at the highest risk?
"That finding was novel in that survivors who were treated for their cancer at a really young age (4 years or younger) seemed to be at a particularly higher risk for developing a severe mental health problem later on (requiring either hospitalization or an emergency room visit). And we don't really know why. Is there something about having had the traumatic experience of cancer at a very young age that somehow predisposes you to problems later? Is it possible that parents change how they parent their kids who have had cancer?
"They may not remember the actual experience of having had cancer. But maybe there's something about the trauma of having cancer-even if you can't remember the details-that has an impact.
"Maybe it's that we haven't historically thought about mental health care in these very young patients, so no attention is paid.
"These are all potential explanations. But, we would need to do more research in these younger patients to understand why we saw this. But it was a pretty striking finding about how much this risk was elevated."
3 What are the most important implications of this research?
"Message one: The complete care of survivors of childhood cancer must expand beyond just thinking about physical consequences, such as new cancer and heart disease. There needs to be a focus on the mental health of these survivors. And that means that those practitioners looking after them as adults, very often family doctors, need to be aware that they should be screening for things like anxiety, depression, PTSD, substance abuse, [and other problems]. Realizing now that this is a population at risk, there needs to be some focus on that risk.
"Two: [We need to look at] whether mental health care resources need to be available or offered more broadly during the pediatric years. Perhaps a more proactive pediatric approach will save patients from running into these mental health issues in adulthood.
"And lastly, another important message is [also] that, though the [mental health] risks are higher for survivors of childhood cancer, many of these survivors are also doing absolutely fine. We can be reassuring [to parents and others] that most kids and adults do absolutely fine, but we do need to be on the lookout for those who are struggling and have a means to get them help sooner rather than later."