Improved Long-Term QOL Observed for Pediatric Cancer Survivors as Treatments Evolve

As treatment approaches continue to evolve, researchers project improved life expectancy after treatment for pediatric cancer, particularly among those who received chemotherapy alone for their childhood cancer diagnosis, according to a study published in JAMA Oncology.¹

However, regardless of the improvements, the researchers also indicated that cancer survivors remain at risk for shorter lifespans, especially when radiotherapy was included as part of their childhood cancer treatment. 

“Our findings highlight the need for continued monitoring of survivors’ health to manage late mortality risks and underscore the need for new therapeutic approaches to minimize early mortality risks, especially for cancer diagnoses for which radiotherapy remains a key component of therapy,” the authors wrote. 

A hypothetical cohort of 5-year survivors of childhood cancer representative of the Childhood Cancer Survivor Study was developed to include late recurrence, treatment-related late effects (health-related [subsequent cancers, cardiac events, pulmonary conditions, etc.] and external causes), and US background mortality rates. Conditional life expectancy was 48.5 years (95% uncertainty interval [UI], 47.6-49.6 years) for survivors diagnosed in 1970-1979, 53.7 years (95% UI, 52.6-54.7 years) for those diagnosed in 1980-1989, and 57.1 years (95% UI, 55.9-58.1 years) for those diagnosed in 1990-1999. 

When compared with individuals who had no history of cancer, the results represented a gap in life expectancy of 25% (95% UI, 24%-27%) OR 16.5 years (95% UI, 15.5-17.5 years) for those diagnosed in 1970-1979; 19% (95% UI, 17%-20%) or 12.3 years (95% UI, 11.3-13.4 years) for those diagnosed in 1980-1989; and 14% (95% UI, 13%-16%) or 9.2 years (95% UI, 8.3-10.4 years) for those diagnosed in 1990-1999. Over the 3 decades, the proportion of survivors treated with chemotherapy alone increased (from 18% in 1970-1979 to 54% in 1990-1999), and the life expectancy gap in this chemotherapy-alone group decreased from 11.0 years (95% UI, 9.0-13.1 years) to 6.0 years (95% UI, 4.5-7.6 years). 

During the same time frame, only modest improvements in the gap in life expectancy were projected for those treated with radiotherapy (21.0 years [95% UI, 18.5-23.2] to 17.6 years [95% UI, 14.2-21.2 years]) or with radiotherapy and chemotherapy (17.9 years [95% UI, 16.7-19.2 years] to 14.8 years [95% UI, 13.1-16.7 years]). For survivors with acute lymphoblastic leukemia, the largest group by diagnosis, the gap in life expectancy decreased from 14.7 years (95% UI, 12.8-16.5 years) in 1970-1979 to 8 years (95% UI, 6.2-9.7 years). 

In an editorial written by Stephanie M. Smith, MD, MPH, of Vanguard Medical Group, Michael P. Link, MD, of Stanford Medicine, and Karen E. Effinger MD, MS, of the Emory Winship Cancer Institute, the authors indicated that the future of prevention for late-effects in this population lies in genomic advances to distinguish susceptibility to treatment-related toxic effects.²

“Identification of cancer predisposition syndromes based on family history and tumor characteristics is just the beginning,” the authors wrote in the editorial. “Although we have come a long way since the early days of pediatric oncology treatment, our work is far from complete.”

The study authors noted multiple areas where more research is necessary, including the need to incorporate quality-of-life aspects to better portray long-term health for children and adolescents who receive a diagnosis of cancer.

References:

1. Yeh JM, Ward ZJ, Chaudhry A, et al. Life Expectancy of Adult Survivors of Childhood Cancer Over 3 Decades. JAMA Oncology. doi:10.1001/jamaoncol.2019.5582.

2. Smith SM, Link MP, Effinger KE. Minding the Gap for Survivors of Childhood Cancer. JAMA Oncology. doi:10.1001/jamaoncol.2019.5556.