Study: Adolescent and Young Adult Leukemia Survivors May Not Live As Long As Their Peers

The 10-year survival beginning five years after diagnosis IS seen as about 10 percent lower than in age-matched general population, a gap that persists for many years, The study reports.

People who were treated for acute leukemia when they were adolescents or young adults (AYAs) may not live as long as their peers in the general population, succumbing to relapse of leukemia or side effects of their treatment, a study found.

AYAs who survived leukemia at least five years after their initial diagnosis were about 10 percent less likely to live another ten years than their peers in the general population, according to the study published in Cancer Epidemiology, Biomarkers & Prevention, a journal of the American Association for Cancer Research.

“The number of AYAs diagnosed with acute leukemia who are being cured from their initial cancer has increased,” said Michael Roth, MD, associate professor, co-director of the Adolescent and Young Adult (AYA) Oncology Program, and director of the Childhood Cancer Survivorship Program at The University of Texas MD Anderson Cancer Center. “These patients have potentially five or more decades of life ahead of them, beyond their cancer diagnosis. Therefore, it is not just important to cure them of their initial cancer, but also to consider their long-term lifespan and quality of life, to make sure they are living long, healthy, and happy lives afterward.” 

Roth and his team studied data on survival after a diagnosis of acute myeloid leukemia (AML) and acute lymphoblastic leukemia (ALL) among people in the AYA age cohort and compared them to mortality data in the general United States population from the same age cohort.

“We started our analysis five years after the initial diagnosis to separate the time when the patients were getting very intensive treatment from the time when they were back to their lives but potentially dealing with late side effects from their initial treatment,” said Roth. 

The researchers found that differences in survival rates between survivors of leukemia in their AYA years and their counterparts in the general population persisted for up to 30 years of follow-up. 

“These patients go through so many challenges during their cancer treatment, and it also appears that they’re going through many more challenges during survivorship,” said Roth. “For example, the mortality of AML survivors continues to increase many decades post treatment, most likely because the majority of these patients undergo stem cell transplant, which is associated with a very high risk and number of late side effects.” 

Leukemia remained the most common cause of death in the early survivorship period. “Some of these patients aren’t being fully cured of their initial cancer, so between five and 10 years post initial diagnosis, most of the deaths are due to disease progression or relapse, whereas after that, most of the deaths result from late side effects from treatment, including cardiovascular disease and secondary cancers,” Roth said.

The researchers also analyzed the impact of age, sex, race/ethnicity, socioeconomic status, and decade of diagnosis on long-term outcomes.

Older age at diagnosis correlated with worse long-term survival outcomes, with each additional year at diagnosis associated with a 6 percent and 5 percent decrease in long-term survival for ALL and AML survivors, respectively. 

Sex of AML survivors was associated with long-term outcomes, with males surviving 61 percent as long as females.

Among survivors of ALL in their AYA years, Asian or Pacific Islanders had longer survival than Hispanics. Hispanic individuals also had a trend toward lower survival time than non-Hispanic white individuals, surviving 56 percent as long as white survivors, although this difference did not reach statistical significance after adjusting for socioeconomic status.

“Historically, patients from ethnic and racial minorities have less access to quality health care, and we worry that they may be receiving less preventative health care to prevent secondary cancers and treat some of the cardiovascular late effects that can occur post leukemia treatment,” said Roth.

The researchers found that long-term survival improved in more recent decades of diagnosis, as the life span of individuals diagnosed in the 1990s and 2000s was more than twice as long as that of individuals diagnosed in the 1980s. This was likely due to treatment advances leading to improved cure rates with lower toxicities, and better supportive care. 

However, there was no further improvement in long-term survival for patients diagnosed in the 2000s compared with the 1990s for either ALL or AML. “We think that we are likely to see much more progress in cure rates over the next two decades, in patients diagnosed from 2010 to 2020, due to newer immunotherapy and targeted agents being used more frequently for these patients.