Although the National Cancer Institute (NCI) has identified adolescents and young adults (AYAs) with cancer as a distinct patient population from children and older adults with the disease, research into the diagnosis, treatment, and survivorship specific to this patient population has not kept pace with research on childhood and adult cancers. There is also little research to help understand the unique biologic and genomic characteristics of malignant tumors in adolescents and young adults—defined by the NCI as those between the ages of 15 and 39—and how those characteristics may be hindering greater survival improvement in this patient population compared with younger children or older adults with cancer.

GUEST EDITOR

Brandon Hayes-Lattin, MD, FACP

Adolescent and Young Adult Oncology explores the unique physical, psychosocial, social, emotional, sexual, and financial challenges adolescents and young adults with cancer face. The column is guest edited by Brandon Hayes-Lattin, MD, FACP, Associate Professor of Medicine and Medical Director of the Adolescent and Young Adult Oncology Program at the Knight Cancer Institute at Oregon Health and Science University in Portland, Oregon.

Although treatment advances have increased the 5-year relative survival rates across all age groups, including a 15% increase for AYAs,¹ it varies widely for some cancers among adolescents and young adults diagnosed with cancer. For example, AYAs have substantially worse 5-year relative survival than children for acute lymphocytic leukemia (ALL), 60% vs 91%, respectively, and worse 5-year relative survival for female breast cancer, 86% vs 91% in older patients.²

Similarly, as in older minority adults with cancer, growing survival disparities exist for minority AYAs and those with low socioeconomic status in many additional cancers, including Hodgkin and non-Hodgkin lymphoma; melanoma; as well as testicular, colorectal, thyroid, renal, pelvic, lung, and cervical, according to a large population-based study by Michael E. Roth, MD; Caitlin C. Murphy, PhD, MPH; and colleagues.³

Caitlin C. Murphy, PhD, MPH

The study estimated the 5-year relative survival associated with 15 common cancers diagnosed in 88,000 adolescents and young adults from 1995 to 2016 using data from the Texas Cancer Registry. The study investigators examined differences in relative survival by race and ethnicity, neighborhood poverty, urban or rural residence, and insurance type. The study included individuals who were non-Hispanic White, non-Hispanic Black, and Hispanic.

“We’ve come a long way in terms of our understanding of the values, care, and outcomes for AYAs with cancer, but there is still a lot we don’t know and need to learn.”

— Michael E. Roth, MD

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The study findings showed that relative 5-year survival rates were worse among Black patients compared with White patients for many cancer types, including non-Hodgkin lymphoma, 74.5% for White patients vs 57% for Black patients; and ALL, 66.5% for White patients vs 44.4% for Hispanic patients. Dr. Roth and his colleagues characterized these differences as “striking.” Survival disparities remained even for cancers with an excellent prognosis, such as testicular cancer, 96.6% for White patients vs 88.7% for Black patients. Being Black was also associated with all-cause mortality across all stages at diagnosis. Another disturbing finding was that survival rates among these patients decreased as their level of poverty increased.³

Determining the Causes of Increases in Cancer in AYAs

Each year, nearly 90,000 adolescents and young adults are diagnosed with cancer, and about 9,300 individuals die of the disease.² Also concerning is the fact that the rate of cancer has increased by 30% in this age group over the past 4 decades.⁴

“We know that the number of adolescents and young adults diagnosed with cancer keeps rising, and that doesn’t take into account all of the patients who go on to relapse or the number of patients who have long-term physical, psychosocial, and financial side effects from their cancer and treatment,” said Dr. Roth, Associate Professor, Department of Pediatrics Patient Care; Co-Director, Adolescent and Young Adult Oncology Program; and Director, Childhood Cancer Survivorship Program, Department of Pediatrics Patient Care, Division of Pediatrics at The University of Texas MD Anderson Cancer Center. “We’ve come a long way in terms of our understanding of the values, care, and outcomes for AYAs with cancer, but there is still a lot we don’t know and need to learn.”

In a wide-ranging interview with The ASCO Post, Dr. Roth discussed the differences in tumor biology that may contribute to worse outcomes in young minority patients; the critical need to enroll more AYAs in clinical trials; and how to improve survival outcomes in minority AYAs.

Understanding Biologic Differences in Tumors in Minority AYAs

In addition to the striking and persistent disparities found in your study in the 5-year relative survival rates of common cancers diagnosed in adolescents and young adults based on race and ethnicity, poverty, and having Medicaid or no insurance, you also found differences in tumor biology in minority patients that may contribute to disparities in survival. Please talk about these differences in tumor biology of these patients.

We have a lot of limitations in terms of what we know about how tumor biology differs within adolescents and young adults and by race and ethnicity and how it may contribute to disparities in relative survival. The most information we currently have on high-risk genomic alterations in AYAs is probably in patients with ALL. We know that chromosomal rearrangements resulting in the overexpression of cytokine receptor-like factor 2 (CRLF2) occur in 50% of Philadelphia like–positive leukemia and that these patients are more difficult to treat. We also know that CRLF2 alterations are more common among Hispanic patients diagnosed with ALL and that Hispanic AYAs have poorer survival compared with other ethnic groups. But we do not know a lot about the distribution of biologic subtypes in racial or ethnic minorities for many AYAs with solid tumors.

We need to better understand if and how biologic subtypes of AYA cancers differentially occur in racial and ethnic minorities, as well as how to differentiate the effects of tumor biology from structural barriers to care. The challenge to understanding tumor biology in these cancers is enrolling more adolescents and young adults into clinical trials, so we can collect their biospecimens and then compare tumor biology within and between people from different races and ethnicities.

We have a long way to go to understand why Black, Hispanic, and other ethnic and minority patients have poorer outcomes compared with White patients independent of socioeconomic status. Tumor biology is a key area to explore. We also need to gain a better understanding of AYAs’ risk for long-term and late effects from treatment, including infertility, sexual dysfunction, cardiovascular disease, and future cancers. In addition, these patients are more likely to experience delays in diagnosis because of lack of insurance.

Our study described these challenges and the differences that exist. However, it is a call to action to understand the “why” behind these differences in survival outcome.

Developing Clinical Trials for AYAs to Improve Outcomes

Clinical trial enrollment for AYAs is the lowest of any patient group with cancer. Why is it so difficult to enroll these patients into clinical trials?

We have done a fair amount of research looking into the psychosocial and institutional barriers and facilitators to enrolling AYAs into clinical trials, and the reasons are multifactorial. Compared with older adults, some AYAs consider cancer clinical trials to be unsafe and have concerns about the trials’ interference in their long-term goals.⁵ Another challenge is the limited communication between pediatric and medical oncology, so oncologists may not know that a trial is locally available for their AYA patients. Other barriers include the perception of a lack of available trials; logistical constraints to accessing trials; and lack of leadership support, sufficient resources, and appropriate policies.

There is a certain cost to launching a clinical trial, and it is more cost-effective to enroll many more patients. It is much easier to enroll patients with breast cancer and prostate cancer into trials, for example, because there are so many patients with these cancers.

“To improve outcomes for all AYAs with cancer…, we need to focus our research efforts on learning more about the unique characteristics of cancer in this age group.”

— Michael E. Roth, MD

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We need to overcome these challenges to improve survivorship in this patient population. We enroll between 30% and 60% of children into clinical trials, and we need to make that same effort in AYA oncology; we are closer to between just 2% and 5% enrollment for AYAs, which is pretty poor.

We have made a lot of progress since 2014 when the NCI Clinical Trials Network launched the National Clinical Trials Network, its new cooperative group system for clinical trial research to improve the speed and efficiency of clinical trials. The new system brought the pediatric oncology network group closer together with the adult oncology network groups, and we are now developing AYA trials collaboratively.

A disturbing trend we are seeing is an increase in cancers typically diagnosed in older adults being diagnosed in younger patients, including early-onset breast and colorectal cancers. What’s even more concerning is that when these cancers develop in AYAs, they are associated with poorer outcomes, which are causing an even more urgent need to focus specifically on this patient population. We know from historical data that we cannot treat AYAs the same way we treat younger or older patients; for many of these cancers, the tumor biology is different.

We also know that AYAs’ ability to tolerate chemotherapy is different, as is their response to treatment. The level of toxicity differs as well.

So, it is important for all these reasons to have a specific focus on the AYA population and have trials that are committed to moving the needle toward better outcomes.

Deciphering the Role of Insurance Type in Survival

In your study, patients with Medicaid coverage had double the risk of all-cause mortality compared with those with private insurance. Why do you think the type of insurance was a factor in relative survival?

We do not have the data to understand why patients with different insurance coverage have different outcomes. We looked at disparities based on insurance, and we assumed access to health care and access to quality health care is the main driver, but we do not have enough data within the AYA population to understand why patients with different insurance coverages have different outcomes.

We do know that AYAs who are uninsured or underinsured are more likely to present with later-stage cancers, so delays in diagnosis are definitely a concern, but I do not think that is the whole picture. We need to understand what happens physically with this patient population with fewer resources or financial means and how they influence their care. Does the treatment approach differ? Are their follow-up points of care with the health-care system different? We just do not have that level of detail yet to understand what is causing these disparities so we can fix the problem and, hopefully, change these outcomes. That is our goal.

Addressing Structural Racism in Medicine

Please talk about the role structural racism in medicine may be playing in perpetuating worse outcomes in minority AYAs.

It is difficult to know specifically within the AYA cancer population why Black patients independent of socioeconomic means have poorer survival outcomes. We need to study this further and understand what is causing this very meaningful disparity. We do know that, in general, Black patients diagnosed with hematologic malignancies seem to be less likely to receive allogeneic stem cell transplantation, perhaps partly because they are underrepresented in national marrow donor registries. However, the extent to which other factors, including racism, are contributing to this disparity is unclear.

Our goal as oncologists is to make sure we do everything we can to help every patient, whether that means cure, improving quality of life, or prolonging life. It is disconcerting to see that these disparities in cancer outcomes and outcomes in other diseases still exist in 2021. I am hoping that more attention will be paid to this issue now and in the future.

Improving Survival in AYAs With Cancer

How can oncologists improve survival outcomes in underserved minority AYAs with cancer?

What we need to do to improve outcomes for all AYAs with cancer, including racial and ethnic minority patients, is to focus our research efforts on learning more about the unique characteristics of cancer in this age group. It is incredible to see how little research has been conducted in AYAs. If we don’t understand what is causing these survival disparities, we can’t lessen or mitigate them.

We know that AYAs face disparities in cancer care and in survival outcomes. And now we know that specific subsets of AYAs with cancer face even worse outcome disparities.

We have moved the needle meaningfully in survival outcomes in pediatric oncology. We need that same level of effort, intensity, and enthusiasm to improve survival in adolescents and young adults with cancer. 

DISCLOSURE: Dr. Roth has received research funding from Eisai and Pfizer.

REFERENCES

1. Coccia PF: Overview of adolescent and young adult oncology. J Oncol Pract 15:235-237, 2019.

2. American Cancer Society: Special Section: Cancer in Adolescents and Young Adults. Available at www.cancer.org/content/dam/cancer-org/research/cancer-facts-and-statistics/annual-cancer-facts-and-figures/2020/special-section-cancer-in-adolescents-and-young-adults-2020.pdf. Accessed August 9, 2021.

3. Murphy CC, Lupo PJ, Roth ME, et al: Disparities in cancer survival among adolescents and young adults: A population-based study of 88,000 patients. J Natl Cancer Inst 113:1074-1083, 2021.

4. Scott AR, Stoltzfus KC, Tchelebi LT, et al: Trends in cancer incidence in US adolescents and young adults, 1973–2015. JAMA Netw Open 3:e2027738, 2020.

5. Lewin J, Bell JAH, Wang K, et al: Evaluation of adolescents’ and young adults’ attitudes toward participation in cancer clinical trials. JCO Oncol Pract 16:e280-e289, 2020.