A tailored breast cancer screening program that delivered screening mammography to 40-49 year old women and then referred them to ultrasound or breast MRI based on lifetime risk and breast density yielded more cancers than expected, with most cancers classified as low-stage disease, according to a study published online April 11 in Radiology.
Elena Venturini, MD, from the department of radiology at San Raffaele Scientific Institute in Milan, and colleagues sought to determine the feasibility, performance and cost of a breast cancer screening program tailored to the risk profile of women ages 40 to 49 years.
In most European countries, women in this group are not screened, despite accumulating evidence indicating high breast cancer incidence. In addition, physicians have recognized that subgroups of women may benefit from supplemental exams, specifically ultrasound or MR.
The researchers recruited 1,666 women ages 40-49 to undergo screening mammography. Women with BI-RADS density 1 or 2 and a lifetime risk for breast cancer lower than 25 percent according to the Gail model underwent microdose mammography only. Those with negative mammograms and BI-RADS breast density 3 or 4 and a lifetime breast cancer risk lower than 25 percent underwent breast ultrasound. Those with a lifetime risk more than 25 percent, a BRCA1 or BRCA2 mutation or other high risk factors underwent contrast-enhanced MRI.
The average lifetime risk of breast cancer was 11.6 percent, and three women had a lifetime risk greater than 25 percent. Another six women were classified as high risk based on previous or family history of breast cancer or history of radiation.
A total of 917 women had BI-RADS density scores of 3 or 4, while 111 had BI-RADS scores of 4 or 5 and were recalled after mammographic abnormalities.
Screening ultrasound was performed in 835 women. Breast MR was performed in nine women.
Breast cancer was diagnosed on 14 women; 12 via mammography (10 of these had high density scores) and two with ultrasound. Four cancers were stage 0, four were stage 1, three were stage 3 and one was stage 4. Tumor size for seven of the 10 invasive ductal carcinomas was less than 15 mm.
The cost of the program was €115, 418 ($151,000), with a cost of €8,244 ($10,790) per cancer diagnosed. It cost €6,377 ($8,345) to detect cancer with mammography and €19,158 ($25,070) with ultrasound.
Most patients had an excellent or good prognosis, according to Venturini et al. “Thus, as some recent studies have stated [breast cancer screening] in women aged 40-49 years enables cancer detection at a lower stage of disease, more frequent conservative treatment, and a reduced rate of recurrence.”
The researchers suggested that their work might spur additional study of mortality reductions of breast cancer screening in this population. They concluded by emphasizing the feasibility and effectiveness of the screening model as well as the high detection rate of asymptomatic low-grade tumors. “These results support the screening of women aged 40-49 years.”
Other recent research has called for a personalized approach to breast cancer screening that leverages an array of adjunctive imaging modalities.