New research reveals substantial differences in childhood cancer rates when considering one year old rather than grouping several years together. The study that Wiley published early online in CANCER, a peer-reviewed journal of the American Cancer Society, also found that minority children have different risks than white children for many types of cancer.
Childhood cancer rates in the United States are usually reported in age groups of 5 years, which can obscure important details. Also, racial and ethnic variations in pediatric cancer rates are typically presented across broad age ranges.
Erin L. Marcotte, PhD, of the University of Minnesota, and her colleagues examined data from 2000-2017 from the Surveillance, Epidemiology, and End Results (SEER) Program, a resource for cancer statistics in the United States, to determine the incidence of cancer to be judged by narrow age groups from birth to 39 years and across races and ethnicities. “There are significant racial and ethnic differences in the incidence of some types of childhood cancer,” said Dr. Marcotte. Furthermore, unlike cancers that occur in older adults, the incidence of cancers in children and young adults shows striking variations by age at diagnosis, and studying these variations has often led to a deeper understanding of the causes of childhood cancers. “
Several cancers showed significant differences by age of one year, both in general and between racial and ethnic groups. Black children, adolescents and young adults had a lower rate of acute lymphoblastic leukemia, or ALL (a cancer of the white blood cells), compared with white children, especially those ages 1 to 7 years and 16 to 20 years. “Black children and young adults had less ALL, the most common childhood leukemia, at any age, but this reduced risk was most marked in children ages 2 to 5, where the incidence of ALL in black children was less than half that of of white children. children,” said Dr. Marcotte.
The researchers also noted that while black children experienced the same incidence of non-Hodgkin’s lymphoma (another white blood cell cancer) as white children, black young adults were at higher risk than white young adults, starting at age 28. higher risk of nephroblastoma, a rare kidney tumor usually diagnosed before age 5.
Hispanic children had a higher risk of Hodgkin lymphoma than white children ages 0 to 9, but had a lower risk at all other ages. They also had lower rates of astrocytoma, a cancer of the brain or spinal cord, but higher rates of ALL, especially those ages 10 to 23. The analysis also revealed that Asian and Pacific islanders and American Indians and Alaskan Natives have lower rates of many childhood cancers.
Some of the patterns we observed may be due to racial and ethnic differences in known risk factors for childhood cancer, such as exposure to infections and birth defects. We also know that the causes of each type of cancer in children and young adults can vary depending on the age at which it occurs. For example, exposure to the Epstein-Barr virus is associated with Hodgkin lymphoma in children younger than 10 years of age, but not in old age. Thus, exposure to the Epstein-Barr virus may explain the higher risk of Hodgkin lymphoma in Hispanic children under the age of 10.”
Erin L. Marcotte, PhD, of the University of Minnesota,
dr. Marcotte hopes this work will play a role in reducing racial and ethnic inequalities in cancer risk in children and young adults.