WEDNESDAY, May 27, 2026 (HealthDay News) -- From 2010 to 2021, there was a significant increase in the incidence of stage IV breast cancer, according to a study published online May 12 in JAMA Network Open.
Jorge Avila, M.D., from the Montefiore Medical Center in Bronx, New York, and colleagues examined incidence, percentage, and survival of people with de novo stage IV breast cancer diagnosed from 2010 through 2021 in a population-based cohort study.
The researchers observed an increase in stage IV incidence, from 9.5 to 11.2 cases per 100,000 women in 2010 and 2021, respectively (annual percentage change [APC], 1.2 percent). There was also an increase in the incidence of stages I to III disease, from 163.0 to 177.4 cases per 100,000 women in 2010 and 2021, respectively. An increase was seen in stage IV incidence across all tumor subtypes, with APCs of 2.0, 1.6, 1.3, and 2.7 percent for hormone receptor (HR)-positive/ERBB2-negative, HR-positive/ERBB2-positive, HR-negative/ERBB2-positive, and triple-negative disease, respectively. The incidence of stage IV disease increased significantly across all age groups and numerically across all racial groups. A significant increase was seen in stage IV incidence among men, with an APC of 3.7 percent. In each tumor subgroup, the percentage of stage IV diagnoses increased significantly from 2010 to 2021.
"This study raises concern because we don't have good answers as to why we are seeing an increase in de novo metastatic breast cancer, regardless of breast cancer subtype," senior author José P. Leone, M.D., from Harvard Medical School in Boston, said in a statement.
Several authors disclosed ties to the biopharmaceutical industry.
