According to government research, new cases of breast cancer in the United States are forecast to rise by as much as 50 percent by the year 2030.
Though the surge in cases will post “a huge challenge” to medical providers over the coming decades, said coauthor Philip S. Rosenberg of the National Cancer Institute, the data also revealed “one silver lining:” a lower incidence of the breast cancer subtype known as estrogen-receptor-negative, including tough-to-treat HER2-positive and triple-negative types.
“Although breast cancer overall is going to increase, different subtypes of breast cancer are moving in different directions and on different trajectories,” Rosenberg said.
He and his National Cancer Institute colleagues shared the new projections in a report at the annual meeting of the American Association for Cancer Research, in Philadelphia on Monday, April 20. The conducive report findings were assembled using cancer incidence data, census data and forecasting models.
The group estimated that the total number of new breast cancer cases would increase from 283,000 in 2011 to around 441,000 in 2030. The proportion of invasive estrogen-receptor-positive cancers was expected to hold steady at 63 percent, while that of estrogen-receptor-positive cancers that had not spread to other body parts was expected to increase, from 19 to 29 percent.
Estrogen-receptor-negative cancers were expected to drop from 17 to 9 percent of the total cases. Rosenberg said the researchers did not know the reasons behind the projected decline, but pointed to “intriguing clues.”
For instance, women who first give birth at a young age and do not breastfeed are at high risk for early onset of this subtype, he noted. More women today, however, delay childbearing and opt to breastfeed, which might help explain the projected drop in certain cases.
The researchers also predicted that the age distribution of women with new breast cancers would change by 2010, with the percentage of new cases occurring in women ages 70-84 expected to increase from 24 to 35 percent, and expected to fall from 55 to 44 percent in women ages 50-69.
The National Cancer Institute said it studied the frequency of breast cancer cases to help oncologists define a “proactive road map” for prevention and treatment in the future.
(With reports from Los Angeles Times)
