Tomosynthesis and the ‘brave new world’ of breast cancer screening

The increased utilization of digital breast tomosynthesis (DBT) represents a dramatic shift in the quality and accuracy of breast imaging and will continue to revolutionize breast cancer screening efforts in the future, according to a recent editorial published in JAMA Oncology.

The contentious debate surrounding mammography screening recommendations has resulted in increased scrutiny of population-based breast cancer screening strategies and spurred additional research into the use of various adjunct imaging tools, including DBT, according to authors Nehmat Houssami, PhD, of the University of Sydney in Australia, and Diana Miglioretti, PhD, of the University of California-Davis.

“None of the currently available adjunct breast imaging technologies seems as promising, or as feasible to implement on a large scale, as digital breast tomosynthesis,” they wrote. “This technology appears to be disseminating throughout the United States faster than the pace witnessed for [digital mammography] in the preceding decade, with 50 percent of facilities in the Breast Cancer Surveillance Consortium now offering DBT.”

Adoption of DBT screening technology has continued to grow despite certain evidence gaps in its diagnostic abilities, said Houssami and Miglioretti. But those gaps are beginning to be filled: A study published in the same issue of the journal investigating the effectiveness of DBT compared with digital mammography showed lower recall rates and improved performance with consecutive DBT screening.

“McDonald et al. convincingly show that, compared with the baseline year in which only [digital mammography] screening was used, screening with adjunct DBT resulted in significantly lower recall rates in each of 3 consecutive years,” they wrote. “In other words, screening with [digital mammography] plus DBT finds as many or more [breast cancers] with fewer false-positive recalls than screening with [digital mammography] alone.”

Despite the promising results, Houssami and Miglioretti cautioned that until the results are replicated under other circumstances—including in other countries with robust screening policies already in place—the jury remains out on just how effective DBT can be as a breast cancer screening tool.

“Whereas this study provides important evidence about the sustainability of reductions in recall rates from adjunct DBT among women without dense breasts, we need to be cautious about generalizing these results,” wrote Houssami and Miglioretti. “It will be important to determine whether the results from this academic medical center with breast imaging specialists can be replicated in other U.S. settings and other countries.”

However, there remains tremendous cause for optimism regarding the future of breast cancer screening, according to the authors, and the continued improvement of diagnostic accuracy through DBT should be a focal point for researchers, doctors, patients and healthcare in general going forward.  

“Importantly, the emergence of DBT, essentially a more detailed mammographic image, compels us to take a fresh look at the best way to deliver [breast cancer] screening moving into the future,” added Houssami and Miglioretti, “considering ‘old’ strategies such as broader adoption of biennial (rather than annual) screening as proposed in new guidelines, and intelligent evaluations of DBT as a primary rather than adjunctive screening tool for the early detection of [breast cancer].”