The typical U.S. woman diagnosed with breast cancer is about 60 years old, white and affluent, according to government data. But breast cancer defies statistics every day.
|Katherine Henderson, left, discusses ongoing studies with Leslie Bernstein (Photo by p.cunningham)|
Breast tumors may develop and grow in any woman, regardless of her ethnicity, age or background. When cancer develops in women younger than 50, in particular, it tends to be more aggressive and offers a poorer prognosis. Yet scientists have run relatively few breast cancer studies on younger women, so they are unsure why these women develop breast cancer, why it is so invasive and how to reduce their risk for it.
City of Hope’s Katherine Henderson, Ph.D., assistant research professor in the Division of Cancer Etiology, will help tackle the complex issue through her partnership in a multimillion-dollar National Cancer Institute (NCI) study.
Through a four-year subcontract of nearly $4.5 million from Michigan State University, Henderson will lead data collection at City of Hope for women in Los Angeles County who are participating in the study. The study, which will be called the Young Women’s Health History Study (YWHHS), is led by Ellen M. Velie, Ph.D., M.P.H., an epidemiologist at Michigan State.
“This area is ripe for research, because there is so much we still need to learn about the risk factors for breast cancer in this younger population,” Henderson said. “By learning about the risk factors that may contribute to the specific subtypes of breast cancer in these women, we may be able to eventually create strategies to modify these risk factors and improve women’s chances of avoiding disease.”
YWHHS researchers will study 1,000 African-American and 1,000 white women diagnosed with breast cancer before age 50 in Los Angeles County and metropolitan Detroit from 2010 to 2014, and compare them to 2,000 women of the same races, age range and residential areas.
Scientists will focus on factors related to “energy balance” during childhood and adulthood. These factors include a woman’s diet and exercise habits over time, as well as patterns in growth, body fat and how her body matured during puberty. The team also will examine women’s levels of insulin resistance — a diabetes-associated condition in which the body’s cells cannot adequately use insulin to absorb blood sugar.
And by analyzing women’s DNA, the scientists will try to determine if common genetic variations in pathways related to en-ergy balance may be linked to breast cancer development.
Although most breast cancers grow in women age 50 and older, breast cancer incidence is rising fastest among women under 50. Young African-American women, in particular, are more likely to have breast tumors that are hormone receptor-negative. “These tumors tend to be more aggressive, and because they do not depend on estrogen or progesterone to grow, they do not respond well to common treatments that suppress these hormones,” Henderson explained.
Recent research suggests that women lower on the socioeconomic scale — those with less education and income — also may be more likely to develop these hormone receptor-negative breast cancers. Through this study, scientists hope to better understand the relationships between energy balance factors and risk for these aggressive tumors, as well as breast cancer risk overall.