Advanced breast cancer concerns raised for young women
medwireNews: US study findings reveal a worrying increase in the incidence of advanced breast cancer in young women in recent years.
Data from the Surveillance, Epidemiology, and End Results (SEER) registries for 1973-2009, 1992-2009, and 2000-2009 show an increase in the number of breast cancers with distant metastasis at diagnosis in women aged 25 to 39 years, from 1.53 to 2.90 cases per 100,000.
The researchers say that the absolute difference of 1.37 cases per 100,000 is a "relatively small" increase but it may have growing clinical significance as there is no suggestion the average 2.07% increase per year is likely to end.
"The trajectory of the incidence trend predicts that an increasing number of young women in the United States will present with metastatic breast cancer in an age group that already has the worst prognosis, no recommended routine screening practice, the least health insurance, and the most potential years of life," warn Rebecca Johnson (Seattle Children's Hospital and University of Washington, USA) and co-authors.
The rise in breast cancer with distant disease at diagnosis in young women occurred across all racial groups, the researchers say, with significant increases noted for African-American and non-Hispanic White women. And the increase did not significantly differ between young women residing in metropolitan and nonmetropolitan areas.
Between 1992 and 2009, there was an 8.15 and 8.89 annual percent change (APC) increase in the diagnosis of 25 to 39 year old women with distant disease with estrogen receptor (ER)- and progesterone receptor (PR)-positive disease, and ER-positive PR-negative disease, respectively. By contrast, the APC was -0.51 for women with ER-negative PR-negative breast cancer.
"This finding is comparatively fortunate in that breast cancer patients with distant involvement and ER+PR+ disease have a median survival of approximately 45 months vs a median survival of only 25 months for women with ER-PR- disease," the researchers comment but note that 10-year survival rates are less than 20% in both groups.
There was no increase in the incidence of localized or regional breast cancer diagnoses in young women, or an increase in localized, regional, or distant breast cancer in women of other age groups.
Commenting on the findings in JAMA, Johnson et al say they found no evidence to suggest that the increase in advanced disease among young women is due to stage migration.
"Whatever the causes-and likely there are more than 1-the evidence we observed for the increasing incidence of advanced breast cancer in young women will require corroboration and may be best confirmed by data from other countries," they conclude.
medwireNews (www.medwirenews.com) is an independent clinical news service provided by Springer Healthcare Limited. © Springer Healthcare Ltd; 2013
By Lynda Williams, Senior medwireNews Reporter