A new study finds breast cancer is diagnosed earlier in the U.S. than in Europe, which helps explain differences in breast cancer survival rates between women in the two regions. The difference was particularly apparent among elderly women. The finding appears in the journal Cancer.

Previous studies have shown that women in the U.S. have significantly higher survival rates than women in Europe. But determining the reason has been challenging. Scientists have hypothesized with little significant evidence that differences in treatment and access to healthcare may account for the higher American survival rates. However, one recent study suggested women in the U.S. are diagnosed earlier than European women.

To investigate further the reasons for transatlantic disparities in breast cancer survival rates, an international team of researchers compared population-based data from 4,478 women diagnosed in 6 countries contributing to the EUROCARE study (Estonia, France, Italy, Spain, The Netherlands, UK) and 13,172 American women recorded in the SEER program from 1990-1992. At that time the SEER program and the data used here from the EUROCARE study covered only 10 percent and 14 percent, respectively, of the population in the countries involved.

The authors report that early stage tumors were reported in 41 percent of cases in the U.S.'s SEER database compared to only 29 percent of cases in the European EUROCARE database. In the U.S., early stage disease was more frequently reported for elderly women aged 65 or over (43 percent) than for women less than 65 years old (38 percent) while early stage disease was reported in only 25 percent of elderly women and 31 percent of younger women in Europe.

While most women received surgery, tumors tended to be significantly larger among elderly European women than among elderly American women. Finally, overall five-year survival was significantly greater in U.S. women than among European women (89 percent versus 79 percent).

The authors conclude, "the results therefore suggest that more resources should be invested to achieve earlier diagnosis of breast cancer in Europe, especially for elderly women."

SOURCE:
Cancer, February 15, 2004, published online December 29, 2003