Cancer incidence in U.S. adolescent and young adult (AYA) women stratified by race/ethnicity and region.
Authors: Zhao Jing , Chiao Elizabeth Y. , Mazul Angela Liu , Deshmukh Ashish , Malpica Luis , Patel Tejal Amar , Kizub Darya Aleksandrovna 
Published: June 2022

e18529 Background: Cancer incidence is higher in AYA women compared to men and is increasing. National trends by race/ethnicity and region for AYA women in the U.S. are needed to improve health care outcomes. Methods: Data about the top ten cancers 2001-2017, race/ethnicity, and 9 CDC divisions were extracted from US Cancer Statistics Public databases encompassing 99% of US population. Age-adjusted incidence and its annual percent change (APC) were generated using SEER*Stat and trends analyzed via joinpoint regression. All statistical tests were two sided. Results: The top ten cancers in AYA women were: breast (incidence of 26.7 per 100,000), thyroid (16.0), melanoma (11.5), cervical (8.8), colorectal (4.1), uterine (3.5), non-Hodgkin lymphoma (3.6), Hodgkin lymphoma (4.0), and leukemia (3.1). Hispanic women had the highest incidence of uterine and cervical cancer and leukemia. Incidence of breast and colorectal cancer and non-Hodgkin lymphoma was highest in NH Black. Thyroid and colorectal cancer, melanoma, and Hodgkin lymphoma incidences were highest in NH White. Incidence trends included: 1) rise in breast (APC 0.5%), uterine (2.9%) in 2001-2017, and colorectal cancer (2.2% 2001-2013; 6.7% 2013-2017); 2) thyroid cancer (APC 2.1-7.2%) 2001-2015; (-5.7%) 2015-2017; 3) melanoma (-1%) 2005-2017; 4) cervical cancer (-1.4%) 2001-2013; 5) non-Hodgkin lymphoma (-0.5%) in 2007-2017; 5) Hodgkin lymphoma (-0.9%) 2007-2017; 6) leukemia (2.4%) 2001-2012 (p < 0.05). Incidence trends by race/ethnicity included: 1) breast cancer rise in all groups except for NH Black; 2) thyroid cancer rise in all 2001-2015; fall in NH White 2015-2017; 3) melanoma fall in Hispanic and NH Other, rise in NH White 2001-2005); 4) cervical cancer decline in all, Hispanic 2001-2013; 5) colorectal and uterine cancer rise in all; 6) fall in non-Hodgkin lymphoma in NH Black 2005-2017; rise in NH Other; 8) fall in Hodgkin lymphoma in NH White; 7) ovarian cancer rise in Hispanic; 8) leukemia rise in all, NH black 2001-2015 (p < 0.05). Division incidence trends included: 1) breast cancer rise in New England and Middle Atlantic (APC 0.7%); 2) colorectal cancer rise in New England (3.5%) and Mountain (4%); 3) melanoma fall in West South Central (-1.1%); 4) cervix cancer fall in West South Central (-0.3%) and South Atlantic (-0.7%); 5) uterine cancer rise in East North Central (2.3%), South Atlantic (3.0%), and West South Central (4.3%); 6) non-Hodgkin lymphoma rise (0.54%) in Pacific; 7) leukemia rise in South Atlantic (2.4%) and West South Central (0.9%) (p < 0.05). Conclusions: Breast, colorectal, uterine cancer, and leukemia incidence rose in AYA women, while thyroid and cervical (2001-2013) cancer, melanoma and lymphoma incidence fell, with variation by race/ethnicity and division. Research to describe environmental, lifestyle, and healthcare/policy factors and correlate them with outcomes is an urgent unmet need to improve equity in cancer outcomes.