North of England Cancer Network
HER2 testing Audit
Anna Long and Judith Hogarth
Cellular Pathology
Newcastle upon Tyne Hospitals NHS Foundation Trust
We will cover…
 HER2 testing – an introduction
 Audit parameters
 Aims
 Results
 Summary
 Limitations
HER2
 HER2 is a trans-membrane tyrosine kinase that mediates cell
growth and survival
 HER2 signalling induces cell proliferation
 Herceptin® binds to HER2 receptors and inhibits
proliferation by disrupting HER2 mediated downstream
signalling
 Only those patients that exhibit elevated expression of the
HER2 antigen will benefit from treatment
Getting the test right is critical!
HER2 testing
 HER2 status is routinely used in breast cancer testing and is
recognised as a prognostic and predictive marker.
 Eligibility for treatment assessed by immunocytochemistry
and/or in situ hybridisation
IHC
0
1+
Negative
2+
3+
Equivocal
Positive
ISH
If < 2.0 =
Non-amplified
If ≥ 2.0 =
Amplified
NECN HER2 testing
 At time of audit, undertaken by three centres in the NECN
 Gateshead Health NHS Foundation Trust (QEH)
 Newcastle upon Tyne Hospitals NHS Foundation Trust (RVI)
 North Tees and Hartlepool NHS Foundation Trust (UHNT)
Centre
Tests referred
from
IHC
method
ISH
performed?
ISH method
QEH
QEH
SRH
UHND
Dako
HercepTest
No, referred to RVI
N/A
RVI
RVI
CRI
NTGH
Ventana 4B5
Yes
Ventana SISH
UHNT
UHNT
JCUH
Ventana 4B5
No, referred to
Source BioScience
N/A
(Vysis FISH at Source
BioScience)
UKNEQAS
 All centres performing HER2 testing must
participate in the relevant NEQAS HER2 IHC
and ISH modules
 UKNEQAS cite two recommended HER2 testing
guidelines:
 ASCO/CAP (Wolff et al. 2006)
 UK updated guidelines (Walker et al. 2008)
Walker et al. (J Clin Path)
 Laboratories undertaking tests should be defined by each
Cancer Network.
 UK minimum laboratory workload:
 250 IHC cases per annum
 100 ISH cases per annum
 Total HER2 positive cases: 15-17%
 Total IHC 2+ HER2 cases: average range 18-19%
 Number of IHC 2+ cases that exhibit HER2 gene
amplification: 17-24%
Aims of the audit
Are centres within the cancer network meeting these
standards?
Therefore we have established within the NECN:
(1) How many tests are performed by each centre
(2) The HER2 positivity rate
(3) The number of 2+ cases generated by IHC
(4) The number of 2+ cases that exhibit HER2 gene
amplification
Data collected from January 2011-December 2012 inclusive
(1) How many tests are performed by each centre
Number of IHC tests performed annually
2011
2012
standard
1400
Number of tests
1200
1000
800
600
400
200
0
QE
RVI
UHNT
Centre
All centres meet minimum benchmark for IHC tests
performed
Number of ISH tests performed annually
2011
2012
standard
350
300
Number of tests
250
200
150
100
50
0
QE
RVI
Source BioScience (UHNT)
Centre
*Equivocal QE cases stained using SISH at RVI, UHNT cases performed by Source BioScience
All centres meet minimum benchmark for ISH tests
performed
In summary (1) – Minimum number of
tests performed
 All centres satisfy the minimum requirement for number
of IHC and ISH tests performed.
(2) HER2 positivity rate
NECN HER2 profile – positivity
25
20
461/2816
426/2974
% cases
15
10
16.4
14.3
5
0
2011
2012
Year
2011 - Positive vs. negative rates fits within the standard set out
by Walker et al (15-17%).
2012 sees this rate drop 0.7% outside this range.
Positivity profile for each centre
20.0
18.0
145/794
135/764
145/867
16.0
135/976
181/1185
Quoted range 2006-2007 = 15-17%
% cases
14.0
UKNEQAS data 2009-2012= 14.5%
148/1212
12.0
10.0
8.0
17.7
13.7
15.3
12.2
16.7
18.3
2011
2012
2011
2012
2011
2012
6.0
4.0
2.0
0.0
QEH
RVI
Year by centre
UHNT
 RVI and UHNT fell within the expected positivity range in 2011.
QEH rate slightly above expected range in 2011 = 17.7%
Both QE and RVI have seen a drop in the positivity rate in 2012 (below 15%)
UHNT has shown an increase in positivity rate in 2012 (above 17%).
Positivity rates - QEH and RVI
QEH
25
60/297
20
48/269
56/362
27/199
60/508
10
5
15.5
11.8
18.1
13.1
20.2
15
5
2011
2012
QEH
2011
2012
2011
SRH
Year by referring hospital
Positivity rate of cases has
dropped across all hospitals
(range = 2.4 - 5.0%)
2012
UHND
77/523
53/406
66/495
52/412
30/305
10
17.8
0
51/256
20
% positive cases
% positive cases
19/105
15
RVI
25
13.1
12.6
14.7
13.3
19.9
9.8
2011
2012
2011
2012
2011
2012
0
CRI
RVI
Year by referring hospital
NTGH
Positivity rate of cases has
dropped across all hospitals
(range = 0.5 - 10.1%)
NTGH positivity rate has more
than halved (19.9 – 9.8%)
Positivity rates in referring hospitals UHNT
25
63/317
20
% positive cases
63/376
82/477
82/491
15
10
5
16.8
19.9
16.7
17.2
2011
2012
2011
2012
0
JCUH
UHNT
Year by referring hospital
Positivity rate of cases has increased across all hospitals (range = 0.5 - 3.1%)
In summary (2) – Positivity rates
 The NECN as a whole falls below the expected frequency of
positive HER2 cases.
 The audit period spans 2011-2012, however the published literature
details HER2 cases from 2006-2007.
 UKNEQAS data spanning 2009-2012, quotes a positive rate of
14.5%, which means the NECN in fact meets the expected frequency
of positive cases.
 2/3 referral centres in 2012 fell below 14.5% (QEH and RVI)
 QEH – all referring hospitals showed a similar decline in positivity rate
This would suggest some common factor ?the test itself.
 RVI - one referral hospital (NTGH) showed a marked decline in
positivity rate (19.9-9.8%)
This would suggest an upstream factor is responsible for the observed
shift.
(3) 2+ cases generated by IHC
2+ rate for NECN
22
UKNEQAS data 2009-2012 = 21.7%
20
Av. Quoted range 2006-2007 = 18-19%
18
16
% cases
14
12
10
8
6
15.6
13.9
2011
2012
4
2
0
Year
The NECN falls below the quoted range for the whole audit period, and
significantly below the UKNEQAS data.
2+ rate for centres
UKNEQAS data 2009-2012 = 21.7%
20
209/1230
% 2+ rate
15
112/764
180/1193
10
5
Av. Quoted range 2006-2007 = 18-19%
152/889
123/810
87/986
16.0
8.8
15.1
17.0
17.1
15.2
2011
2012
2011
2012
2011
2012
0
QEH
RVI
Year by centre
UHNT
RVI and UHNT have shown <2% variation in 2+ rate.
QEH sees a 7.2% decrease
% 2+ rates for referring hospitals QEH
18
18/107
16
58/363
14
36/300
% 2+ rate
12
52/518
10
16/199
8
19/269
6
16.0
10.0
16.8
8.0
2011
2012
2011
2012
12.0
7.1
4
2
0
QEH
SRH
Year by hospital
2011
2012
UHND
Fall in 2+ rate observed in all hospitals (range = 4.9 – 8.8%)
Most significant decrease seen in SRH cases – more than halved.
% 2+ rates for referring hospitals
- RVI and UHNT
RVI
UHNT
25
25
69/312
20
20
88/503
15
63/417
57/409
80/527
64/386
77/501
% 2+ rate
% 2+ rate
43/257
10
5
13.9
15.1
15.2
15.4
16.7
49/322
15
74/488
10
22.1
16.6
15.2
17.5
15.2
2011
2012
2011
2012
5
0
2011
2012
CRI
2011
2012
RVI
Year by hospital
2011
2012
NTGH
Small increase seen in CRI and
RVI cases (1.2% and 0.2 %
respectively).
Significant increase seen in
NTGH cases (5.4%)
0
JCUH
UHNT
Year by hospital
Small decrease seen in JCUH
and UHNT cases
(1.4% and 2.3% respectively).
In summary (3) – 2+ rate
 2+ rate within NECN falls below the frequency cited in
published and UKNEQAS data.
 RVI and UHNT saw slight (<2%) fluctuations in 2+ rate
between 2011 and 2012.
 QEH showed a 7.2% decrease in 2+ reporting
 All referring hospitals showed a decrease in 2+ rate (4.9-8.8%
fall – SRH rate more than halved).
(4) 2+ cases that exhibit HER2 gene amplification
Number of 2+ cases that exhibit HER2 gene
amplification - NECN
25
Av. Quoted range 2006-2007 = 17-24%
20
70/441
% cases
15
49/406
UKNEQAS data 2009-2012 = 14.7%
10
5
15.9
12.1
0
2011
2012
Year
There has been a decline in the number of 2+ cases that exhibit HER2 gene
amplification (3.8%).
2+ cases that exhibit HER2 gene amplification
by centre
25
% cases
20
53/292
15
16/118
33/288
17/149
18.2
11.5
11.4
13.6
2011
2012
2011
2012
10
5
0
QEH/RVI
UHNT
Year by centre performing test
UHNT HER2 gene amplified cases increased 2.2%.
RVI saw a decrease of 6.7% in 2+ cases that demonstrated gene
amplification….Why is this?
Amplified ISH performed at RVI
40.0
7/19
35.0
13/43
% amplified cases
30.0
25.0
17/80
3/16
20.0
Quoted range 2006-2007 = 17-24%
3/18
9/57
5/36
15.0
11/77
6/58
UKNEQAS data 2009-2012 = 14.7%
8/69
6/63
10.0
0/52
5.0
10.3
0.0
16.7
18.8
13.9
36.8
15.8
9.5
21.3
14.3
30.2
11.6
2011
2012
2011
2012
2011
2012
2011
2012
2011
2012
2011
2012
0.0
QEH
SRH
UHND
CRI
Year by referring hospital
RVI
NTGH
There is significant variation in the reporting of HER2 gene amplified cases
(range 0-36.8%).
Most significant outliers = QEH (decrease of 10.3% to 0% amplified),
UHND (increase of 22.1%), NTGH (decrease of 18.6%)
Amplified ISH UHNT cases (Source BioScience)
20.0
18.0
11/69
16.0
14.0
12.0
7/64
%
9/85
5/49
10.0
8.0
6.0
4.0
2.0
10.6
15.9
10.9
10.2
2011
2012
2011
2012
0.0
UHNT
JCUH
Year by referring hospital
There is variation in the reporting of HER2 gene amplified cases
(range 0.7-5.3%).
In summary (4) – 2+ amplified cases
 There is marked variation in the positivity rate by HER2 gene
amplification.
 Significant outliers
 QEH (0% amplified 2012)
 UHND (increase of 22.1% from 2011 to 2012)
 NTGH (decrease of 18.6% from 2011 to 2012)
 This may be a symptom of variable 2+ rate by IHC
In summary
Change in rates 2011 – 2012 by hospital
Hospital
Change in
positivity rate
(%)
Change in 2+
rate (%)
Change in
amplified 2+ rate
(%)
QEH
 2.2
 6.0
 10.3
SRH
 5.0
 8.8
 2.1
UHND
 2.4
 4.9
 22.9
NTGH
 10.1
 5.4
 18.6
RVI
 1.4
 0.2
 7.0
CRI
 0.5
 1.2
 6.3
UHNT
 0.5
 2.3
 5.3
JCUH
 3.1
 1.4
 0.7
Limitations
Limiting factors
Limitations
Pre-analytical
Analytical
Post-analytical
Cold ischaemia time
Subjective
interpretation
Subjective
interpretation
Core vs excision
Chosen HER2 test
Staffing
Fixation
Methodology of test
Reporting confidence
Processing
Staining platforms
Decalcification
Drying time
We need standardisation!
Future considerations
 Look at 2013 data?
Thank you
Trudy Johnson - QEH
Sharron Williams, Jim France – UHNT
Merdol Ibrahim - UKNEQAS
Immunocytochemistry colleagues, RVI
Thank you for listening…
Questions?
References:
Walker et al. HER2 testing in the UK: further update to recommendations. J Clin Path. 2008:61; 818-824.
Wolff et al. American Society of Clinical Oncology/college of American Pathologists guideline recommendations for
HER2 testing in breast cancer. J Clin Oncol. 2007: 25; 1-28.
Ibrahim M. UKNEQAS HER2 audit data. UKNEQAS. 2009-2012. Personal communication.