[Screening digital mammography: one year result for the Alpes-Maritimes region]

After one year of experience with screening digital mammography, the results of this technique (n=9640) are compared to screen-film mammography (n=240 376) with double reading.

Evaluation for each technique of the rate of call-back, positive results before and after work-up by the first reader and distribution based on the BI-RADS classification by the ACR, rate of complementary US, detected abnormalities (microcalcifications) and detected cancers.

The rate of positive mammograms was significantly higher for the digital technique (17.3% versus 15.1%) because of the first reader (16.3% versus 13.9%) whereas it was significantly lower after complementary work-up (3% versus 3.7%). The rate of BI-RADS 0 was significantly higher with digital imaging irrespective of patient age. The rate of US was higher for type 1 and 2 breasts at digital imaging (46% versus 36%, p<0.0001) while the reverse was true for denser breasts (49% versus 54%; p:0.0005). More microcalcifications were detected on digital imaging (24.4% versus 21.8%) without impact on the rate of DCIS and invasive carcinomas. The rate of cancers detected with both technique were identical.

The increased number of positive results at first reading and increased number of US for digital mammography may relate to a learning curve and difficulties in comparing with prior examinations. These results should continuously be monitored and compared to national averages.