Standardization of whole slide image morphologic assessment with definition of a new application: Digital slide dynamic morphometry.
BACKGROUND
In histopathology, the quantitative assessment of various morphologic features is based on methods originally conceived on specific areas observed through the microscope used. Failure to reproduce the same reference field of view using a different microscope will change the score assessed. Visualization of a digital slide on a screen through a dedicated viewer allows selection of the magnification. However, the field of view is rectangular, unlike the circular field of optical microscopy. In addition, the size of the selected area is not evident, and must be calculated.


METHODS
A digital slide morphometric system was conceived to reproduce the various methods published for assessing tumor budding in colorectal cancer. Eighteen international experts in colorectal cancer were invited to participate in a web-based study by assessing tumor budding with five different methods in 100 digital slides.


RESULTS
The specific areas to be tested by each method were marked by colored circles. The areas were grouped in a target-like pattern and then saved as an .xml file. When a digital slide was opened, the .xml file was imported in order to perform the measurements. Since the morphometric tool is composed of layers that can be freely moved on top of the digital slide, the technique was named digital slide dynamic morphometry. Twelve investigators completed the task, the majority of them performing the multiple evaluations of each of the cases in less than 12 minutes.


CONCLUSIONS
Digital slide dynamic morphometry has various potential applications and might be a useful tool for the assessment of histologic parameters originally conceived for optical microscopy that need to be quantified.
Division of Pathology, G. Fracastoro, City Hospital, Verona.
Giacomo
G
Puppa
Mauro
M
Risio
Kieran
K
Sheahan
Michael
M
Vieth
Inti
I
Zlobec
Alessandro
A
Lugli
Sara
S
Pecori
Lai Mun
LM
Wang
Cord
C
Langner
Hiroyuki
H
Mitomi
Takatoshi
T
Nakamura
Masahiko
M
Watanabe
Hideki
H
Ueno
Jacques
J
Chasle
Carlo
C
Senore
Stephen A
SA
Conley
Paulette
P
Herlin
Gregory Y
GY
Lauwers