Reproducibility study – Leica Biosystems Bond Oracle HER2 IHC System User Manual
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Leica Biosystems Bond Oracle HER2 IHC System Instructions for Use TA9145 EN-CE-Rev_E 18/06/2013
Reproducibility Study
Within and Between Precision Testing
Precision testing was performed at Leica Biosystems, Newcastle Ltd. The tissue used was a
formalin-fixed, paraffin-embedded composite tissue micro array (TMA) supplied by Isu Abxis
(Yonsei University Medical Center 134 Shinchon-dong, Seoul, 120-752 Korea), comprising
of 20, 4mm diameter invasive breast carcinoma tissue cores.The 20 cases were selected
based on previously assigned HER2 scores. On this basis, x5 cases of HER2 3+, x5 cases of
HER2 2+, x5 cases of HER2 1+ and x5 cases of HER2 0, were included.
A. Within Run Precision Testing
Within run precision testing of the Bond Oracle HER2 IHC Systems was evaluated on a
total of 40 consecutive sections from a TMA comprising of 20 invasive breast tumors and
40 HER2 Control Slides. All slides were stained with the Bond Oracle HER2 IHC System on
the BOND fully automated advanced staining system. Sections were stained during one
continuous period using a Bond Oracle HER2 IHC System from the same manufacturing
batch. Stained sections were blinded and assessed in a randomized fashion by a single
experienced observer to determine within run precision.
An evaluation of the slides from the within run investigation indicated that 733/800 (91.63%)
test data points could be interpreted. 40 data points were excluded due to presence of
DCIS only, and a further 27 data points could not be interpreted due to a loss of invasive
tumor (specific to 3 cores). Variation in staining occurred 61 (8.32%) out of a possible
733 staining events. On 37 occasions, variation from 3+ to 2+ (n = 20) and from 1+ to
0 (n = 17) was observed and would therefore not represent a change from clinically positive
to clinically negative or vice versa in a 2x2 data assessment. The remaining 24 (3.27%)
occasions represented a change from clinically negative (0 or 1+) to clinically positive
(2+ or 3+). Pass value = 96.7% (95% CI = 95.15% to 97.81%).
B. Between Run Precision Testing
Between run precision testing of the Bond Oracle HER2 IHC System was evaluated on a
total of 24 consecutive sections taken from a TMA comprising of 20 invasive breast tumors
and 24 HER2 Control Slides. All slides were stained with the Bond Oracle HER2 IHC
System on the BOND fully automated advanced staining system. The slides were evaluated
in 8 independent runs, performed within the same laboratory, on three separate occasions
using a Bond Oracle HER2 IHC System from the same manufacturing batch. Stained slides
were blinded and assessed in a randomized fashion by a single experienced observer to
determine between run precision.
An evaluation of the slides from the between run investigation indicated that 456/480
(95.00%) test data points could be interpreted. 24 data points could not be interpreted due
to a loss of invasive tumor (specific to 5 cores). Variation in staining occurred 42 (9.21%) out
of a possible 456 data points. On 30 occasions, variation from 3+ to 2+ (n = 10) and from
1+ to 0 (n = 20) were observed and would therefore not represent a change from clinically
positive to clinically negative or vice versa in a 2x2 data assessment. The remaining 12
(2.63%) represented a change from clinically negative (0 or 1+) to clinically positive
(2+ or 3+). Pass value = 97.37% (95% CI = 95.90% to 98.77%).
C. Lot-to-Lot Reproducibility
To determine Lot-to-Lot reproducibility, 3 lots of Bond Oracle HER2 IHC Systems were
manufactured under GMP on 3 separate occasions and evaluated on 24 breast tumor
sections (24 test data points) taken from four different formalin-fixed, paraffin-embedded
tissue blocks (representing 0, 1+, 2+ and 3+ HER2 staining intensities) and three HER2
Control Slides (12 control data points). Three independent runs were performed within the
same laboratory on three separate occasions, each using a separate manufacturing lot of
Bond Oracle HER2 IHC System. All slides were stained with the Bond Oracle HER2 IHC
System on board a BOND fully automated advanced staining system. Stained slides were