In a sobering analysis, researchers warn that those who've had childhood cancer are highly likely to face physical and mental health challenges later in life, with 95 percent developing a "significant health problem" related to their cancer or treatment by age 45.
The researchers reviewed 73 studies, including 39 cohort studies that followed patients over time. Publishing their findings in JAMA, they said approximately 15,000 children and adolescents through age 19 are diagnosed with cancer every year and that 85 percent of children now live five years or more beyond their diagnosis. That's compared with just 58 percent in the 1970s, according to the American Cancer Society.
The research documented a variety of concerns for young cancer survivors, ranging from subsequent hormone issues to reproductive health challenges, problems with muscles and bones, cognitive impairment and more.
Among those childhood cancer survivors with later health problems, the researchers write, approximately one-third will go through "severe or potentially life-threatening chronic health problems." Most common were endocrine disorders, subsequent neoplasms (abnormal growths) and cardiovascular disease.
Many new cancers appeared in places that had undergone radiation during treatment, with radiation fields on the chest, brain, neck, and abdomen or pelvis of "particular concern." Those with higher radiation doses had higher risk, experiencing everything from breast cancer to central nervous system tumors and basal cell carcinoma.
The type of childhood cancer also affected risk.
Those diagnosed with a brain tumor, treated with cranial irradiation or who underwent allogeneic hematopoietic stem cell transplantation - a treatment that gives stem cells from a healthy donor to a sick recipient - were at highest risk, the researchers write.
Mental health was another concern, with depression rates ranging from 2.3 to 40.8 percent compared with a nationwide average of 9.6 percent. Suicide risk was also higher for those who'd undergone cancer as children, with the highest risk in people 28 and older. Compared with the general population, adults who survived childhood cancer had a 1.4-fold higher risk of death by suicide than their counterparts who hadn't been sick as children.
Given the ongoing risk, the researchers recommend that survivors "receive lifelong care focused on health promotion and early detection of potential complications from their cancer treatment."
They encourage providers to inform patients about the potential long-term effects of treatment, and say survivors should get annual physicals and preventive care.