Long-term Survival Trends Among AYAs With the Highest Mortality Cancer Types

While the 5-year relative survival for multiple cancer types in adolescents and young adults (AYAs) has improved, there are some cancer types with limited improvements, according to a new study in Cancer. In addition, while there have been improvements in colorectal cancer, the incidence of this cancer has risen.

The authors used recent data to analyze the long-term survival trends for the cancer types with the highest mortality rates among AYAs. They used the Surveillance, Epidemiology, and End Results 18 registries to calculate 5-year relative survival for AYAs diagnosed with cancer between the ages of 15 and 39 years in 2009-2015. The National Center for Health Statistics was used to calculate US cancer mortality rates per 100,000 in 2012-2016.

They found that the incidence rate for AYAs diagnosed was 74.96 cases of cancer per 100,000 and the mortality rate of any cancer type was 9.01 deaths per 100,000. The 9 cancer types with the highest incidence rates were not the same as the 9 cancer types with the highest mortality rate.

The types with the highest mortality were female breast cancer; brain and other nervous system cancers; cervical cancer; colon and rectum cancer; bone, joint, and soft tissue sarcomas; ovarian cancer; lung and bronchus cancer; acute myeloid leukemia (AML); and non-Hodgkin lymphoma. Breast cancer had the highest incidence (22.41 cases per 100,000), while lung and bronchus cancer had the lowest (1.03 per 100,000).

The trend analysis found:

• Female breast cancer: 5-year relative survival increased from 1985 to 2007 and then stayed stable. Mortality declined from 1986 to 2012 but increased since 2012.
• Brain and other nervous system cancers: 5-year relative survival increased steadily from 1975 to 2011 and incidence was stable since 1987. Mortality decreased from 1994 to 2007 and became stable.
• Cervical cancer: 5-year relative survival was more than 80% in 1975 and remained steady through 2011, but disease burden decreased slightly after 2005.
• Bone, joint, and soft tissue sarcomas: 5-year relative survival significantly increased from 1975 to 1989 before leveling off. From 1975 to 2016 there has been increased incidence. While survival improved for bone and joint, there has been no significant improvement in survival for soft tissue sarcoma.
• Ovarian cancer: 5-year survival rose slightly, and the incidence has been stable since 1996.
• Lung cancer: 5-year relative survival improved greatly between 1998 and 2011 and mortality and incidence both declined.
• AML: 5-year relative survival improved from just over 10% in 1975 to more than 60% in 2011. The incidence increased since 1987, but mortality declined through the 1980s, stabilizing from 1988 to 2008, before declining again.
• Non-Hodgkin lymphoma: 5-year relative survival improved largely between 1992 and 2003 and continued improving slightly from 2003 to 2011. During the HIV epidemic, incidence increased (1983 to 1991), before stabilizing. Meanwhile, mortality decreased.

One of the key limitations to the study is that the mortality data only includes those who died of cancer between the ages of 15 and 39 years, and as a result, “do not perfectly reflect death rates among these individuals who were diagnosed between the ages of 15 and 39 years.” Some of the deaths include those diagnosed before the age of 15 years, and those who died in their 40s or later were not included.

“Our findings underscore the need for additional research to understand cancers showing poorer progress,” the authors concluded. “Substantial concern remains regarding the high number of breast cancers coupled with declining survival rates, the increases in colorectal cancer incidence, and the slow progress for sarcomas and AML, which suggest investigations of biological differences among AYA patients and efforts to further improve treatment in this group.”

Reference

Riedel Lewis D, Siembida EJ, Seibel NL, Wilder Smith A, Mariotto AB. Survival outcomes for cancer types with the highest death rates for adolescents and young adults, 1975-2016. Cancer. Published online July 26, 2021. doi:10.1002/cncr.33793