Friedewald
at al report in a JAMA article a retrospective analysis of performance metrics of
Tomosynthesis and Digital Mammography from 13
academic and nonacademic breast centers.
Patients
were studied under two different protocols: those who
had digital mammography screening alone and those who in addition to digital
mammography, tomosynthesis was added .
A total of 454 850 examinations (n=281 187 digital mammography; n=173 663 digital mammography +
tomosynthesis) were evaluated. With digital mammography, 29 726 patients were recalled and 5056
biopsies resulted in cancer diagnosis in 1207 patients (n=815 invasive; n=392
in situ). With digital mammography + tomosynthesis, 15 541 patients were recalled and 3285
biopsies resulted in cancer diagnosis in 950 patients (n=707 invasive; n=243 in
situ). Model-adjusted rates per 1000 screens were as follows: for recall rate,
107 (95% CI, 89-124) with digital mammography vs 91 (95% CI, 73-108) with
digital mammography + tomosynthesis; difference, –16 (95% CI, –18 to –14; P < .001); for biopsies, 18.1 (95% CI, 15.4-20.8) with digital
mammography vs 19.3 (95% CI, 16.6-22.1) with digital mammography +
tomosynthesis; difference, 1.3 (95% CI, 0.4-2.1; P = .004); for cancer detection, 4.2 (95% CI, 3.8-4.7) with digital
mammography vs 5.4 (95% CI, 4.9-6.0) with digital mammography + tomosynthesis;
difference, 1.2 (95% CI, 0.8-1.6; P < .001); and for invasive cancer detection, 2.9 (95% CI, 2.5-3.2)
with digital mammography vs 4.1 (95% CI, 3.7-4.5) with digital mammography +
tomosynthesis; difference, 1.2 (95% CI, 0.8-1.6; P < .001). The in situ cancer detection rate was 1.4 (95% CI,
1.2-1.6) per 1000 screens with both methods. Adding tomosynthesis was
associated with an increase in the positive predictive value for recall from
4.3% to 6.4% (difference, 2.1%; 95% CI, 1.7%-2.5%; P < .001) and for biopsy from 24.2% to 29.2% (difference, 5.0%; 95%
CI, 3.0%-7.0%; P < .001).
The
authors conclude the addition of tomosynthesis
to digital mammography was associated with a decrease in recall rate and an
increase in cancer detection rate.
An editorial by Drs. Pisano and Yaffe on Tomosynthesis appears in the same issue of JAMA.
