Radiological review of interval breast cancers following screening with DBT + DM or DM: results from MAITA project randomized trials.

purposeCompare the radiological characteristics of screening images preceding interval cancers that occurred in women screened with digital breast tomosynthesis (DBT) plus digital mammography (DM) vs. those in women screened with DM alone. MATERIALS AND

methodsFrom two randomized trials comparing DBT + DM vs. DM, 91 (43 from DBT + DM arm and 48 from DM arm) images preceding interval cancers and 190 (94 and 96, respectively) negative controls were reviewed by three radiologists using only DM screening mammograms and by three different radiologists using all available images, i.e. DBT and DM for the experimental arm and DM for the standard arm. The cancers were classified according to the number of reviewers that found abnormalities, as true negative (negative for all three reviewers), minimal sign (positive for one and negative for two), and false negative (positive for two or three reviewers).

resultsIn the DM arm, interval cancers were classified as true negative in 29-42%, minimal signs in 31-35%, and false negative in 27-35%; in the DBT arm, the proportion of true negative was 40%, minimal signs 21%, and false negatives 40% when the review was performed using only DM images, 30%, 28%, and 42% when the reviewers read both DBT and DM screening images. The differences were compatible with random fluctuations.

conclusionThe radiological analysis of interval cancers after DBT + DM and after DM alone showed similar characteristics, confirming that the impact of DBT on interval cancer incidence is small both in terms of quantity and type.