Tomosynthesis could be cost-effective for Breast Cancer Detection

Lee at al in their article in Radiology report on the effectiveness of combined biennial digital mammography and tomosynthesis, compared with biennial digital mammography alone to screen women aged 50-74 with dense breasts for breast cancer.

For the base-case analysis, the incremental cost per quality-adjusted life year gained by adding tomosynthesis to digital mammography screening was $53 893. An additional 0.5 deaths were averted and 405 false-positive findings avoided per 1000 women after 12 rounds of screening. Combined screening remained cost-effective (less than $100 000 per quality-adjusted life year gained) over a wide range of incremental improvements in test performance. Overall, cost-effectiveness was most sensitive to the additional cost of tomosynthesis.

Biennial combined digital mammography and tomosynthesis screening for U.S. women aged 50–74 years with dense breasts is likely to be cost-effective if priced appropriately (up to $226 for combined examinations versus $139 for digital mammography alone) and if the reported interpretive performance metrics of improved specificity with tomosynthesis are met in routine practice.

They concluded biennial digital mammography combined with tomosynthesis screening for women aged 50–74 years with dense breasts is likely to be cost-effective if priced appropriately (up to $226 for combined examinations versus $139 for digital mammography alone) and if specificity reported from tomosynthesis is achieved among the many practices across the country.

Tomosynthesis detects more breast cancers

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.