In the 1970s, cancer survival was poor for young children and older adults in the United States, as shown by data published in the Journal of the National Cancer Institute.
Great progress has been made since the 1970s, but improvements in outcome have been less impressive for cancer patients aged 15-39 years, as shown by research published in Cancer.
Patients aged 15-39 years have been designated by the National Institutes of Health (NIH) as “adolescents and young adults (AYAs),” and the lag in survival benefit has been termed “the AYA gap.”
The AYA gap persists in lymphoma patients, and an expert panel recently outlined differences between lymphoma in AYAs and lymphoma in other age groups.
The experts spoke at a special session of the AACR Virtual Meeting: Advances in Malignant Lymphoma moderated by Somali M. Smith, MD, of the University of Chicago.
Factors that contribute to the AYA gap
About 89,000 AYAs are diagnosed with cancer each year in the United States, according to data from the National Cancer Institute (NCI). Lymphomas and thyroid cancer are the most common cancers among younger AYAs, aged 15-24 years.
In a report commissioned by the NIH in 2006, many factors contributing to the AYA gap were identified. Chief among them were:
- Limitations in access to care.
- Delayed diagnosis.
- Inconsistency in treatment and follow-up.
- Long-term toxicity (fertility, second malignancies, and cardiovascular disease).
These factors compromise health-related survival, even when cancer-specific survival is improved.
Panelist Kara Kelly, MD, of Roswell Park Comprehensive Cancer Center in Buffalo, N.Y., noted that there are additional unique challenges for AYAs with cancer. These include:
- Pubertal changes.
- Developmental transition to independence.
- Societal impediments such as insurance coverage and disparities in access to specialized centers.
- Psychosocial factors such as health literacy and adherence to treatment and follow-up.
Focusing on lymphoma specifically, Dr. Kelly noted that lymphoma biology differs across the age spectrum and by race and ethnicity. Both tumor and host factors require further study, she said.
Clinical trial access for AYAs
Dr. Kelly emphasized that, unfortunately, clinical research participation is low among AYAs. A major impediment is that adult clinical trials historically required participants to be at least 18 years old.
In addition, there has not been a focused effort to educate AYAs about regulatory safeguards to ensure safety and the promise of enhanced benefit to them in NCI Cancer Trials Network (NCTN) trials. As a result, the refusal rate is high.
A multi-stakeholder workshop, convened in May 2016 by the American Society of Clinical Oncology and Friends of Cancer Research, outlined opportunities for expanding trial eligibility to include children younger than 18 years in first-in-human and other adult cancer clinical trials, enhancing their access to new agents, without compromising safety.
Recently, collaborative efforts between the adult and children’s NCTN research groups have included AYAs in studies addressing cancers that span the age spectrum, including lymphoma.
However, as Dr. Kelly noted, there are differences in AYA lymphoid malignancy types with a transition from more pediatric to more adult types.