TUESDAY, July 29 (HealthDay News) -- The typical U.S. breast cancer screening strategy results in women being tested twice as often as a different approach use in Norway, but both are equally good at detecting disease, a new report says.
A study in the July 29 online issue of the Journal of the National Cancer Institute finds that a traditional physician- and self-referral screening strategy held up well against the Norway approach, in which the government sends letters to all women in a specific age range inviting them to have a screening mammogram. The Norway program aims for women to be screened every two years, while the U.S.-based "opportunistic screening" strategies advise women to have annual screening mammograms.
In comparing the strategies as applied to 45,050 women in Vermont and 194,430 women in Norway from 1997 to 2003, the researchers found that the age-adjusted screening detection rate of cancers was similar between the two populations (2.77 per 1,000 woman-years in Vermont versus 2.57 in Norway).
However, more than three times as many women in Vermont were recalled for further examination than in Norway (9.8 percent versus 2.7 percent).
When all cancers detected during regular screening and between screening mammograms were combined, no substantial differences were found in the prognostic features of invasive cancers detected in the two populations.
Given the shorter interval between screenings, the report's authors hypothesized that "Vermont women and/or their health care providers may more readily pursue evaluation of symptoms and clinical findings than their Norwegian counterparts."
"Our results demonstrate that despite its longer screening interval, the organized population-based screening program in Norway achieved similar outcomes as the opportunistic screening in Vermont," the team wrote.
The U.S. National Institute on Cancer has more about breast cancer.