Abstract
Objective: In order to raise the accuracy of the combined use of mammography (MMG) and breast ultrasonographic examinations (US), the standardization of the procedure through a change from single criterion to combined criteria evaluation is underway. We studied the current situation of combined criteria evaluation in our facility regarding focal asymmetric density (FAD) in MMG and tumor solid mass findings in in order to clarify the usefulness of combined criteria.
Methods: In a total of 5,519 subjects who underwent combined MMG and US examinations from January 2013 to June 2014, we conducted a comparison of single criterion MMG and combined criteria evaluation using FAD findings and tumor mass findings.
Results: FAD findings: The number of subjects requiring further detailed examination for MMG single criterion evaluation was 81 (1.5%). On the other hand, regarding those requiring further detailed examinations on the basis of combined criteria evaluation, 35 subjects who were judged as not requiring further examination by US (findings in the same location, category 2 benign lesions visualized in 12 subjects, normal mammary gland in 23 subjects) were eliminated, reducing the number requiring further detailed examination to 46 (0.8%). In a comparison by direction of imaging, there was no significant difference in reduction rate (p=0.6485). Tumor mass findings: The rate for requiring further detailed examination for MMG single criterion evaluation was 73 subjects (1.3%). For combined criteria, the elimination of 29 subjects with benign lesions visualized in US reduced the number requiring further examination to 44 (0.8%). In the comparison by direction of imaging, there was a much greater reduction in those requiring further examination for 2-direction imaging than 1-direction imaging (p=0.029).
Conclusion: Combined criteria evaluation enabled determination of whether a finding was mammary gland overlap or a tumor mass and was useful in preventing the selection of those with benign lesions for further examinations, thereby leading to a reduction in the further detailed examination rate.
