Comparison of two-dimensional synthesized mammograms versus original digital mammograms alone and in combination with tomosynthesis images.
OBJECTIVE
To assess interpretation performance and radiation dose when two-dimensional synthesized mammography (SM) images versus standard full-field digital mammography (FFDM) images are used alone or in combination with digital breast tomosynthesis images.


METHODS
A fully crossed, mode-balanced multicase (n = 123), multireader (n = 8), retrospective observer performance study was performed by using deidentified images acquired between 2008 and 2011 with institutional review board approved, HIPAA-compliant protocols, during which each patient signed informed consent. The cohort included 36 cases of biopsy-proven cancer, 35 cases of biopsy-proven benign lesions, and 52 normal or benign cases (Breast Imaging Reporting and Data System [BI-RADS] score of 1 or 2) with negative 1-year follow-up results. Accuracy of sequentially reported probability of malignancy ratings and seven-category forced BI-RADS ratings was evaluated by using areas under the receiver operating characteristic curve (AUCs) in the random-reader analysis.


RESULTS
Probability of malignancy-based mean AUCs for SM and FFDM images alone was 0.894 and 0.889, respectively (difference, -0.005; 95% confidence interval [CI]: -0.062, 0.054; P = .85). Mean AUC for SM with tomosynthesis and FFDM with tomosynthesis was 0.916 and 0.939, respectively (difference, 0.023; 95% CI: -0.011, 0.057; P = .19). In terms of the reader-specific AUCs, five readers performed better with SM alone versus FFDM alone, and all eight readers performed better with combined FFDM and tomosynthesis (absolute differences from 0.003 to 0.052). Similar results were obtained by using a nonparametric analysis of forced BI-RADS ratings.


CONCLUSIONS
SM alone or in combination with tomosynthesis is comparable in performance to FFDM alone or in combination with tomosynthesis and may eliminate the need for FFDM as part of a routine clinical study.
From the Department of Radiology, Magee Womens Hospital, University of Pittsburgh Medical Center, 300 Halket St, Pittsburgh, PA 15213 (M.L.Z., V.J.C., D.M.C., A.E.K., A.H.L., G.Y.R., M.L.S., J.H.S., L.P.W.); Department of Radiology, University of Pittsburgh School of Medicine, Pittsburgh, Pa (M.L.Z., V.J.C., D.M.C., A.E.K., A.H.L., G.Y.R., M.L.S., J.H.S., L.P.W.); and Department of Biostatistics, School of Public Health, University of Pittsburgh, Pittsburgh, Pa (B.G., A.I.B.).
Margarita L
ML
Zuley
Ben
B
Guo
Victor J
VJ
Catullo
Denise M
DM
Chough
Amy E
AE
Kelly
Amy H
AH
Lu
Grace Y
GY
Rathfon
Marion
M
Lee Spangler
Jules H
JH
Sumkin
Luisa P
LP
Wallace
Andriy I
AI
Bandos
D000328:Adult; D000368:Aged; D001706:Biopsy; D001943:Breast Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D005260:Female; D006801:Humans; D008327:Mammography / Q000379:methods*; D008875:Middle Aged; D015588:Observer Variation; D011829:Radiation Dosage; D011856:Radiographic Image Enhancement / Q000379:methods*; D011857:Radiographic Image Interpretation, Computer-Assisted / Q000379:methods; D012189:Retrospective Studies