US cancer centers have justified the creation of Adolescent and Young Adult (AYA) oncology programs based on the “survival gap”: the observation that improvement in AYA cancer survival over the past 30 is inferior to that of children and older adults. Recent articles have questioned the significance of this gap, noting that AYAs have the highest 5-year survival of any age group.
We present a novel method for visualizing AYA survival outcomes over time by age of diagnosis using “heat maps.”
We analyzed relative survival for all cancers in 5-year age intervals and by year of diagnosis between 1975 and 2005, in the National Cancer Institute’s SEER9, SEER13, and SEER18 registries. Ages 15 to 39 were defined as AYA. Survival percentages are colored based on their value. Greener shades indicate greater survival, while redder shades indicate inferior survival.
Between 1975 and 1979, 5-year survival was 59.8% among children, 71.3% among AYAs and 47.1%, among older adults. The 2000 to 2004 5-year survivals are 80.2% for children, 80.6% for AYAs, and 63.3% for older adults. Initially, AYAs had the highest 5-year survival of all age groups. During the 1980’s and 1990’s, survival increased dramatically in first children and then in older adults, but increased much less in AYAs. Heat maps also visually demonstrate age-related temporal trends in cancer survival, such as the increased cancer mortality related to non-Hodgkin’s lymphoma and Kaposi’s sarcoma in young males during the early years of the HIV/AIDS epidemic.
Heat maps provide a novel method of demonstrating AYA survival trends over time on one axis and across age groups on a secondary axis. Despite having the highest 5-year survival rates for all age groups, AYAs have had the lowest survival improvement over the past 30 years.