Mammographic density: Comparison of visual assessment with fully automatic calculation on a multivendor dataset.
OBJECTIVE
To compare breast density (BD) assessment provided by an automated BD evaluator (ABDE) with that provided by a panel of experienced breast radiologists, on a multivendor dataset.


METHODS
Twenty-one radiologists assessed 613 screening/diagnostic digital mammograms from nine centers and six different vendors, using the BI-RADS a, b, c, and d density classification. The same mammograms were also evaluated by an ABDE providing the ratio between fibroglandular and total breast area on a continuous scale and, automatically, the BI-RADS score. A panel majority report (PMR) was used as reference standard. Agreement (κ) and accuracy (proportion of cases correctly classified) were calculated for binary (BI-RADS a-b versus c-d) and 4-class classification.


RESULTS
While the agreement of individual radiologists with the PMR ranged from κ = 0.483 to κ = 0.885, the ABDE correctly classified 563/613 mammograms (92 %). A substantial agreement for binary classification was found for individual reader pairs (κ = 0.620, standard deviation [SD] = 0.140), individual versus PMR (κ = 0.736, SD = 0.117), and individual versus ABDE (κ = 0.674, SD = 0.095). Agreement between ABDE and PMR was almost perfect (κ = 0.831).


CONCLUSIONS
The ABDE showed an almost perfect agreement with a 21-radiologist panel in binary BD classification on a multivendor dataset, earning a chance as a reproducible alternative to visual evaluation.


CONCLUSIONS
Individual BD assessment differs from PMR with κ as low as 0.483. An ABDE correctly classified 92 % of mammograms with almost perfect agreement (κ = 0.831). An ABDE can be a valid alternative to subjective BD assessment.
Research and Development Department, im3D S.p.A., Turin, Italy. daniela.sacchetto@i-m3d.com.
Daniela
D
Sacchetto
Research and Development Department, im3D S.p.A., Turin, Italy.
Lia
L
Morra
Research and Development Department, im3D S.p.A., Turin, Italy.
Silvano
S
Agliozzo
APSS, Trento, Italy.
Daniela
D
Bernardi
KTH, Royal Institute of Technology, School of Technology and Health, Stockholm, Sweden.
Tomas
T
Björklund
ISPO, Florence, Italy.
Beniamino
B
Brancato
Centro Prevenzione Oncologica, Ravenna, Italy.
Patrizia
P
Bravetti
IRCCS Policlinico San Donato, San Donato Milanese, Milan, Italy.
Luca A
LA
Carbonaro
Research and Development Department, im3D S.p.A., Turin, Italy.
Loredana
L
Correale
APSS, Trento, Italy.
Carmen
C
Fantò
ASLBi, Biella, Italy.
Elisabetta
E
Favettini
Candiolo Cancer Institute - FPO, IRCCS, Candiolo, Turin, Italy.
Laura
L
Martincich
Regional Reference Centre for Breast Cancer Screening, Turin, Italy.
Luisella
L
Milanesio
Ospedale Valduce, Como, Italy.
Sara
S
Mombelloni
Ospedale S. Martino, Genova, Italy.
Francesco
F
Monetti
ISPO, Florence, Italy.
Doralba
D
Morrone
APSS, Trento, Italy.
Marco
M
Pellegrini
C.d.C, Paideia, Rome, Italy.
Barbara
B
Pesce
IRCCS, National Cancer Institute G. Pascale Foundation of Naples, Naples, Italy.
Antonella
A
Petrillo
AUSL, Bologna, Italy.
Gianni
G
Saguatti
Ospedale Regionale, Bolzano, Italy.
Carmen
C
Stevanin
IRCCS Policlinico San Donato, San Donato Milanese, Milan, Italy.
Rubina M
RM
Trimboli
APSS, Trento, Italy.
Paola
P
Tuttobene
APSS, Trento, Italy.
Marvi
M
Valentini
OIRM S.Anna, Turin, Italy.
Vincenzo
V
Marra
Regional Reference Centre for Breast Cancer Screening, Turin, Italy.
Alfonso
A
Frigerio
Research and Development Department, im3D S.p.A., Turin, Italy.
Alberto
A
Bert
IRCCS Policlinico San Donato, San Donato Milanese, Milan, Italy.|Department of Biomedical Sciences for Health, Università degli Studi di Milano, Milan, Italy.
Francesco
F
Sardanelli
D000071060:Breast Density; D001943:Breast Neoplasms / Q000145:classification / Q000000981:diagnostic imaging*; D001330:Electronic Data Processing / Q000379:methods*; D005260:Female; D006801:Humans; D042361:Mammary Glands, Human / Q000002:abnormalities*; D008327:Mammography / Q000379:methods*; D009367:Neoplasm Staging / Q000379:methods*; D012372:ROC Curve; D015203:Reproducibility of Results
Automated system; BI-RADS density classification; Breast density; Digital mammography; Multireader/multivendor