Five-year Survival Trends for Young Adult Cancers Diagnosed from 2002 to 2014 in Taiwan and the United States.

BACKGROUND

Young adult cancer incidence has been increasing in Taiwan, but no studies have examined their survival trends.

METHODS

We analyzed data from the Taiwan National Health Insurance Research Database and the U.S. Surveillance, Epidemiology, and End Results Program. We obtained the five-year survival estimates and trends for primary invasive cancers diagnosed at 20-39 years of age from 2002 to 2014. When analyzing specific cancers, we focused on the common young adult cancers in Taiwan. For the trend analysis, the average annual percent change (AAPC) was calculated using joinpoint Regression Program. We also obtained estimates stratified by sex or age at cancer diagnosis.

RESULTS

The five-year age-standardized relative survival for all young adult cancers combined significantly increased in Taiwan [AAPC = 1.4%; 95% confidence interval (CI), 1.3%-1.5%] and the United States (AAPC = 0.4%; 95% CI, 0.3%-0.6%). Cancers occurring in both sexes had similar trend directions for both sexes. Lung and bronchus cancer, liver cancer, and leukemia had the most survival improvement in both regions. However, the five-year relative survival for cervical cancer declined in Taiwan (AAPC = -0.6%; 95% CI, -1.0% to -0.1%) and did not improve in the United States (AAPC = -0.1%; 95% CI, -0.4%-0.2%).

CONCLUSIONS

Survival has improved for most but not all of the common young adult cancer types in Taiwan. Additional studies can understand why survival has not improved for certain cancer types, and examine subtype-specific survival trends.

IMPACT

This is the first study of five-year survival trends for young adult cancers in Taiwan and the United States stratified by sex or age at diagnosis.