Multi-institutional comparison of whole slide digital imaging and optical microscopy for interpretation of hematoxylin-eosin-stained breast tissue sections.
BACKGROUND
Whole slide imaging (WSI) is now used for educational purposes, for consultation, and for archiving and quantitation of immunostains. However, it is not routinely used for the primary diagnosis of hematoxylin-eosin-stained tissue sections.


OBJECTIVE
To compare WSI using the Aperio digital pathology system (Aperio Technologies, Inc, Vista, California) with optical microscopy (OM) for the interpretation of hematoxylin-eosin-stained tissue sections of breast lesions.


METHODS
The study was conducted at 3 clinical sites; 3 breast pathologists interpreted 150 hematoxylin-eosin-stained slides at each site, 3 times each by WSI and 3 times each by OM. For WSI, slides were scanned using an Aperio ScanScope and interpreted on a computer monitor using Aperio ImageScope software and Aperio Spectrum data management software. Pathologic interpretations were recorded using the College of American Pathologists breast checklist. WSI diagnoses were compared with OM diagnoses for accuracy, precision (interpathologist variation), and reproducibility (intrapathologist variation). Results were considered accurate only if the interpretation matched exactly between WSI and OM. The proportion of accurate results reported by each pathologist was expressed as a percentage for the comparison of the 2 platforms.


RESULTS
The accuracy of WSI for classifying lesions as not carcinoma or as noninvasive (ductal or lobular) or invasive (ductal, lobular, or other) carcinoma was 90.5%. The accuracy of OM was 92.1%. The precision and reproducibility of WSI and OM were determined on the basis of pairwise comparisons (3 comparisons for each slide, resulting in 36 possible comparisons). The overall precision of WSI was 90.5% in comparison with 92.1% for OM; reproducibility of WSI was 91.6% in comparison with 94.5% for OM, respectively.


CONCLUSIONS
In this study, we demonstrated that WSI and OM have similar accuracy, precision, and reproducibility for interpreting hematoxylin-eosin-stained breast tissue sections. Further clinical studies using routine surgical pathology specimens would be useful to confirm these findings and facilitate the incorporation of WSI into diagnostic practice.
From the Department of Pathology, The University of Texas MD Anderson Cancer Center, Houston (Drs Krishnamurthy, Gilcrease, and Albarracin and Mr Bassett); the Laboratory Diagnostics Medical Group, Scripps Memorial Hospital, La Jolla, California (Drs Mathews, Spinosa, and Chang); the Department of Pathology and Lab Medicine, Presbyterian Hospital, Charlotte, North Carolina (Drs McClure, Holt, and Cohen); the Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, New York (Drs Murray and Giri); Genoptix Medical Laboratory, Carlsbad, California (Dr Ho); the Department of Pathology, University of California at San Francisco School of Medicine (Dr Garg); and MileStone Research Organization, San Diego, California (Dr Liang).
Savitri
S
Krishnamurthy
Kurt
K
Mathews
Steven
S
McClure
Melissa
M
Murray
Michael
M
Gilcrease
Constance
C
Albarracin
John
J
Spinosa
Bernard
B
Chang
James
J
Ho
John
J
Holt
Arthur
A
Cohen
Dilip
D
Giri
Karuna
K
Garg
Roland L
RL
Bassett
Kevin
K
Liang
D001943:Breast Neoplasms / Q000175:diagnosis* / Q000473:pathology; D018270:Carcinoma, Ductal, Breast / Q000175:diagnosis / Q000473:pathology; D018275:Carcinoma, Lobular / Q000175:diagnosis / Q000473:pathology; D003937:Diagnosis, Differential; D003952:Diagnostic Imaging / Q000379:methods / Q000592:standards; D004801:Eosine Yellowish-(YS); D005260:Female; D006416:Hematoxylin; D006651:Histocytochemistry / Q000379:methods*; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods / Q000592:standards*; D008853:Microscopy / Q000379:methods / Q000592:standards*; D061848:Optical Imaging / Q000379:methods / Q000592:standards*; D015203:Reproducibility of Results
D004801:Eosine Yellowish-(YS); D006416:Hematoxylin