A simple scoring system for breast MRI interpretation: does it compensate for reader experience?
OBJECTIVE
To investigate the impact of a scoring system (Tree) on inter-reader agreement and diagnostic performance in breast MRI reading.


METHODS
This IRB-approved, single-centre study included 100 patients with 121 consecutive histopathologically verified lesions (52 malignant, 68 benign). Four breast radiologists with different levels of MRI experience and blinded to histopathology retrospectively evaluated all examinations. Readers independently applied two methods to classify breast lesions: BI-RADS and Tree. BI-RADS provides a reporting lexicon that is empirically translated into likelihoods of malignancy; Tree is a scoring system that results in a diagnostic category. Readings were compared by ROC analysis and kappa statistics.


RESULTS
Inter-reader agreement was substantial to almost perfect (kappa: 0.643-0.896) for Tree and moderate (kappa: 0.455-0.657) for BI-RADS. Diagnostic performance using Tree (AUC: 0.889-0.943) was similar to BI-RADS (AUC: 0.872-0.953). Less experienced radiologists achieved AUC: improvements up to 4.7 % using Tree (P-values: 0.042-0.698); an expert's performance did not change (P = 0.526). The least experienced reader improved in specificity using Tree (16 %, P = 0.001). No further sensitivity and specificity differences were found (P > 0.1).


CONCLUSIONS
The Tree scoring system improves inter-reader agreement and achieves a diagnostic performance similar to that of BI-RADS. Less experienced radiologists, in particular, benefit from Tree.


CONCLUSIONS
• The Tree scoring system shows high diagnostic accuracy in mass and non-mass lesions. • The Tree scoring system reduces inter-reader variability related to reader experience. • The Tree scoring system improves diagnostic accuracy in non-expert readers.
Department of Biomedical Imaging and Image-guided Therapy, Division of Molecular and Gender Imaging, Medical University of Vienna, Vienna General Hospital, Floor 7F Waehringer Guertel 18-20, 1090, Vienna, Austria.|Department of Biomedical Sciences and Morphologic and Functional Imaging, Policlinico Universitario G. Martino, University of Messina, Messina, Italy.
Maria Adele
MA
Marino
Department of Biomedical Imaging and Image-guided Therapy, Division of Molecular and Gender Imaging, Medical University of Vienna, Vienna General Hospital, Floor 7F Waehringer Guertel 18-20, 1090, Vienna, Austria.|Department of Medical and Biological Sciences, Institute of Diagnostic Radiology, Azienda Ospedaliero-Universitaria, "S. Maria della Misericordia", P.le Santa Maria della Misericordia, University of Udine, Udine, Italy.
Paola
P
Clauser
Department of Biomedical Imaging and Image-guided Therapy, Division of Molecular and Gender Imaging, Medical University of Vienna, Vienna General Hospital, Floor 7F Waehringer Guertel 18-20, 1090, Vienna, Austria.
Ramona
R
Woitek
Department of Biomedical Imaging and Image-guided Therapy, Division of Molecular and Gender Imaging, Medical University of Vienna, Vienna General Hospital, Floor 7F Waehringer Guertel 18-20, 1090, Vienna, Austria.
Georg J
GJ
Wengert
Department of Biomedical Imaging and Image-guided Therapy, Division of Molecular and Gender Imaging, Medical University of Vienna, Vienna General Hospital, Floor 7F Waehringer Guertel 18-20, 1090, Vienna, Austria.
Panagiotis
P
Kapetas
Department of Biomedical Imaging and Image-guided Therapy, Division of Molecular and Gender Imaging, Medical University of Vienna, Vienna General Hospital, Floor 7F Waehringer Guertel 18-20, 1090, Vienna, Austria.
Maria
M
Bernathova
Department of Biomedical Imaging and Image-guided Therapy, Division of Molecular and Gender Imaging, Medical University of Vienna, Vienna General Hospital, Floor 7F Waehringer Guertel 18-20, 1090, Vienna, Austria.
Katja
K
Pinker-Domenig
Department of Biomedical Imaging and Image-guided Therapy, Division of Molecular and Gender Imaging, Medical University of Vienna, Vienna General Hospital, Floor 7F Waehringer Guertel 18-20, 1090, Vienna, Austria.
Thomas H
TH
Helbich
Diagnosezentrum Meidling, Vienna, Austria.
Klaus
K
Preidler
Department of Biomedical Imaging and Image-guided Therapy, Division of Molecular and Gender Imaging, Medical University of Vienna, Vienna General Hospital, Floor 7F Waehringer Guertel 18-20, 1090, Vienna, Austria. pascal.baltzer@meduniwien.ac.at.
Pascal A T
PA
Baltzer
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001940:Breast / Q000000981:diagnostic imaging*; D001943:Breast Neoplasms / Q000175:diagnosis*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008875:Middle Aged; D011336:Probability; D012372:ROC Curve; D012189:Retrospective Studies
Breast cancer; MRI; Reader experience; Scoring system; Sensitivity and specificity