Download Personalised Medicine in Colorectal Cancer?

Personalised Medicine in
Colorectal Cancer?
Mr Arfon G M T Powell MB ChB MSc MRCSEd
Clinical Research Fellow in Surgery
Colorectal cancer is the third most common
cancer in the UK
39,991 new cases
in 2008
Cancer Reseach UK. Bowel cancer statistics – UK, 2011. http://info.cancerresearchuk.org/cancerstats/types/bowel/
• CRC is the 2nd most common cause of cancer-death
• Accounting for 16,259 deaths in 2009
Cancer Mortality - UK statistics 2009
Others 53%
Lungs 22%
Bowel 10%
Breast 8%
Prostate 7%
Cancer Reseach UK. Cancer Mortality – UK Statistics 2011. http://info.cancerresearchuk.org/cancerstats/mortality/
Treatment
• Treatment regimens are currently based on
disease stage
• Surgery
• Chemotherapy
– Curative
– Palliative
• Biological therapy
Prognosis
• Prognosis still remains stage dependent
– Dukes’ A  93%
– Dukes’ B  77%
– Dukes’ C  48%
Cancer Reseach UK. Bowel cancer statistics – UK, 2011. http://www.cancerresearchuk.org/cancer-help/type/bowel-cancer/treatment/statistics-and-outlook-forbowel-cancer#outlook
Surgical approach to colorectal cancer
http://www.hopkinscoloncancercenter.org/CMS/CMS_Page.aspx?CurrentUDV=59&CMS_Page_ID=1F7C07D4-268D-4635-8975-70A594870CC8
Variation in biomarker prognostic value
Colorectal cancer development
• Accumulation of genetic alterations – Vogelstein
Microsatellite Instability Phenotype
• Distinct genomic instability pathway
• Microsatellite repeats
• Associated with loss of mismatch repair
protein (MMR) function
• Improved outcome
Söreide K, Janssen EA, Söiland H, Körner H, Baak JP. Microsatellite instability in colorectal cancer. Br J Surg 2006; 93:395-406.
CpG Island Methylator Phenotype
Hypermethylation of cytosine- and guanine-rich
stretches of DNA, called CpG islands, in the promoter
region of genes causes transcriptional silencing and
has been implicated in carcinogenesis
CIMP +ve
MSI/CIMP+
CIMP status
MSI
CIMP -ve
MSI/CIMP-
Microsatellite
stability
status
CIMP +ve
MSS/CIMP+
MSS
CIMP status
CIMP -ve
MSS/CIMP-
Good survival
CIMP +ve
MSI/CIMP+
CIMP status
MSI
CIMP -ve
MSI/CIMP-
Microsatellite
stability
status
CIMP +ve
MSS/CIMP+
MSS
CIMP status
CIMP -ve
Poor survival
MSS/CIMP-
CIMP +ve
MSI/CIMP+
Prognostic information
remains unclear
CIMP status
MSI
CIMP -ve
MSI/CIMP-
Microsatellite
stability
status
CIMP +ve
MSS/CIMP+
MSS
CIMP status
CIMP -ve
MSS/CIMP-
Serrated Adenocarcinoma
• Proximal location
• MSI positive
• Outcome variable which depends on tumour
site
Non Serrated Adenocarcinoma
Serrated Adenocarcinoma
http://kathrin.unibas.ch/polyp/bilder/gross/p015-03.jpg
Our experience with performing
MSI and CIMP status analysis on
colorectal tumours
Study design
•
•
•
•
Retrospective study of 750 FFPE tumours
IHC for MMR proteins (MLH1, MSH2, MSH6 and PMS2)
40% tumour required within the section for PCR
MSI PCR analysis of:
– BAT 25
– BAT 26
– MONO 27
– NR-21
– NR-24
Technical issues
• 55% of patients required macroscopic
dissection to the equivalent of 2 10micron
sections
Technical issues
• 55% of patients required macroscopic
dissection to the equivalent of 2 10micron
sections
MSI +ve
MSI -ve
Preliminary results on 233 patients
• Not significantly associated with:
–
–
–
–
–
–
–
–
Increasing age (P=0.168)
Dukes stage (P=0.054)
Poor differentiation (P=0.362)
Vascular invasion (P=0.176)
Anaemia (P=0.192)
Raised CRP (P=0.374)
Hypoalbuminaemia (P=0.541)
Emergency presentation (P=0.943)
• Significantly associated with:
–
–
–
–
–
Right colon location (P<0.001)
Polypoid morphology (P=0.031)
Lower lymph node ratio (P=0.040)
Mucin production (P=0.009)
Serrated adenocarcinoma (P<0.001)
The relationship between MSI status and
cancer-specific survival
P=0.042
CIMP study design
• Extracted DNA requires
bisulfite conversion
• Followed by a methylight
PCR assay for
– CACNA1G
– IGF2
– NEUROG1
– RUNX3
– SOCS1
DNA recovery following bisulfite treatment
• DNA recovery following bisulfite treatment is variable
and does not reach the projected > 75%
Patient
Input (ng)
nano drop (ng/ul)
DNA recovered (ng)
Percentage recovered (%)
1
350
3.9
78
22.3
2
350
4.3
86
24.6
3
350
2.8
56
16.0
4
350
28
560
160.0
5
350
2.5
50
14.3
6
350
3.4
68
19.4
7
350
3.7
74
21.1
8
350
3.4
68
19.4
9
200
0.3
6
3.0
10
300
84
1680
560.0
11
350
1.7
34
9.7
12
200
64
1280
640.0
13
350
3.7
74
21.1
14
300
2.8
56
18.7
15
300
1.5
30
10.0
16
300
4.8
96
32.0
MSI and CIMP status as predictors
of response to treatment
Treatment
A
Curative resection surgery
B
C
Resection surgery + adjuvant therapy (eg. Chemothearpy)
D
Dependent on tumour characteristics
Treatment of colorectal cancer
• Surgery remains the primary modality for cure
• Chemotherapy for high risk patients
– Lymph node involvement
– Locally advanced tumours
• MDT decision
• Difficulty identifying patients that benefit from
chemotherapy
Adjuvant Chemotherapy
• 2 major regimens for CRC treatment:
– FOLFIRI (5-FU, folinic acid [Leucovorin], and
irinotecan [Campostar])
– FOLFOX (5-FU, folinic acid [Leucovorin], and
oxaliplatin [Eloxatin])
Adjuvant Chemotherapy
• 2 major regimens for CRC treatment:
– FOLFIRI (5-FU, folinic acid [Leucovorin], and
irinotecan [Campostar])
– FOLFOX (5-FU, folinic acid [Leucovorin], and
oxaliplatin [Eloxatin])
• Results in context of MSI is conflicting
Conclusions
•
•
•
•
Colorectal cancer tumour heterogeneity exists
Techniques validated
MSI+/CIMP+ confers improved survival
Response to treatment remains unclear
Acknowledgments
I would like to thank Dr David Baty and Christine Black
(Molecular Genetics, Dundee) for their expertise with
the MSI analysis
I would like to thank Rachael Ellis (Molecular Genetics,
Glasgow) for her help with the bisulfite treatments
I would like to thank Clare Orange for her continued
help over the last 3 years!
Thank you!