A Reappraisal of Sex-Specific Cancer Survival Trends Among Adolescents and Young Adults in the United States

Abstract

Background: Cancer survival among adolescents and young adults (AYAs) was previously reported as showing little or no improvement compared to younger or older counterparts. The role of the HIV/AIDS epidemic in the AYA survival deficit has not been evaluated.

Methods: Using cancer registry data from the Surveillance, Epidemiology, and End Results program (SEER 9), we examined sex-specific 5-year relative survival trends for children (0-14 years old), AYAs (15-39 years old), and older adults (40 years and older) diagnosed with cancer during 1973-2009 and followed through the end of 2014. The analysis was conducted with and without Kaposi sarcoma (KS) and lymphomas, and by two time periods: 1973-1977 (before the human immunodeficiency virus/acquired immunodeficiency syndrome [HIV/AIDS] epidemic) and 2005-2009 (after the HIV/AIDS epidemic waned).

Results: A total of 3 209 721 invasive cancer cases were included in the study (27 646 children, 213 930 AYAs, and 2 968 145 older adults; 24 803 children, 178 741 AYAs, and 2 844 062 older adults when KS and lymphoma cases were excluded). We found that 5-year relative survival for AYAs exceeded that of children and older adults before the onset of the HIV/AIDS epidemic (eg, during 1973-1979, 0.58-0.67 among male AYAs as compared with 0.47-0.61 for male children and 0.36-0.42 for male older adults; among female AYAs, the numbers were 0.73-0.77 as compared with 0.51-0.65 for female children and 0.52-0.55 for female older adults); substantially declined during 1983-1997 when HIV/AIDS lacked effective treatment among male AYAs; and returned to be higher than most age groups by the late 1990s after HIV/AIDS was controlled. Nonetheless, comparison of survival improvement between 1973-1977 and 2005-2009 demonstrated less progress in AYAs than other age groups, which was due to AYAs' better baseline survival and larger survival gains among children and older adults in recent years.

Conclusions: Apart from the temporary impact of HIV/AIDS, survival among AYA cancer patients has shown sustained improvement and superiority relative to other age groups. However, these encouraging findings do not negate the distinctive challenges in cancer diagnosis, treatment, and survivorship faced by AYAs.

© The Author(s) 2018. Published by Oxford University Press. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Figures

Figure 1.

Time trends of 5-year relative survival in males by 5-year age group. Data were from the SEER 9 registries, 1973–2009. Survival probability of all invasive cancers including Kaposi sarcoma (KS) and lymphomas are shown in (A) children age 0–14 years, (B) adolescents and young adults (AYAs) age 15–39 years, and (C) older adults age 40 to ≥60 years, respectively. Survival probability of all invasive cancers excluding KS and lymphomas are shown in (D) children age 0–14 years, (E) AYAs age 15–39 years, and (F) older adults age 40 to ≥60 years, respectively.

Figure 2.

Time trends of 5-year relative survival for females by 5-year age group. Data were from the SEER 9 registries, 1973–2009. Survival probability of all invasive cancers including Kaposi sarcoma (KS) and lymphomas are shown in (A) children age 0–14 years, (B) adolescents and young adults (AYAs) age 15–39 years, and (C) older adults age 40 to ≥60 years, respectively. Survival probability of all invasive cancers excluding KS and lymphomas are shown in (D) children age 0–14 years, (E) AYAs age 15–39 years, and (F) older adults age 40 to ≥60 years, respectively.

Figure 3.

Time trends of 5-year relative survival by age group and sex. Data were from the SEER 9 registries, 1973–2009. Analyses for probability of survival from all invasive cancers including Kaposi sarcoma (KS) and lymphomas are shown for (A) males and (B) females. Analyses for probability of survival from all invasive cancers excluding KS and lymphomas are shown for (C) males and (D) females. AYA = adolescents and young adults.

Figure 4.

Comparison of 5-year relative survival for all invasive cancers by sex and age group, 1973–1977 vs 2005–2009. Data from the SEER 9 registries, 1973–2009, were analyzed. Age-specific 5-year relative survival during 1973–1977 and 2005–2009 are plotted separately for (A) males and (B) females. AYA = adolescents and young adults.