Personalised Medicine in Colorectal Cancer?

1. Personalised Medicine in Colorectal Cancer? Mr Arfon G M T Powell MB ChB MSc MRCSEd Clinical Research Fellow in Surgery

2. 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/

3. CRC is the 2nd most common cause of cancer-death • Accounting for 16,259 deaths in 2009 Cancer Reseach UK. Cancer Mortality – UKStatistics 2011. http://info.cancerresearchuk.org/cancerstats/mortality/

4. Treatment • Treatment regimens are currently based on disease stage • Surgery • Chemotherapy • Curative • Palliative • Biological therapy

6. 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-for-bowel-cancer#outlook

7. Surgical approach to colorectal cancer http://www.hopkinscoloncancercenter.org/CMS/CMS_Page.aspx?CurrentUDV=59&CMS_Page_ID=1F7C07D4-268D-4635-8975-70A594870CC8

14. Variation in biomarker prognostic value

15. Colorectal cancer development • Accumulation of genetic alterations – Vogelstein

16. Microsatellite Instability Phenotype • Distinct genomic instability pathway • Microsatellite repeats • Associated with loss of mismatch repair protein (MMR) function • Improved outcome

19. Söreide K, Janssen EA, Söiland H, Körner H, Baak JP. Microsatellite instability in colorectal cancer. Br J Surg 2006; 93:395-406.

21. CpGIslandMethylator 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

25. MSI/CIMP+ CIMP +ve CIMP status MSI CIMP -ve MSI/CIMP- Microsatellite stability status MSS/CIMP+ CIMP +ve MSS CIMP status CIMP -ve MSS/CIMP-

26. Good survival MSI/CIMP+ CIMP +ve CIMP status MSI CIMP -ve MSI/CIMP- Microsatellite stability status MSS/CIMP+ CIMP +ve MSS CIMP status Poor survival CIMP -ve MSS/CIMP-

27. MSI/CIMP+ CIMP +ve Prognostic information remains unclear CIMP status MSI CIMP -ve MSI/CIMP- Microsatellite stability status MSS/CIMP+ CIMP +ve MSS CIMP status CIMP -ve MSS/CIMP-

29. Serrated Adenocarcinoma • Proximal location • MSI positive • Outcome variable which depends on tumour site Serrated Adenocarcinoma Non Serrated Adenocarcinoma http://kathrin.unibas.ch/polyp/bilder/gross/p015-03.jpg

30. Our experience with performing MSI and CIMP status analysis on colorectal tumours

31. 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

32. Technical issues • 55% of patients required macroscopic dissection to the equivalent of 2 10micron sections

33. Technical issues • 55% of patients required macroscopic dissection to the equivalent of 2 10micron sections

34. MSI +ve MSI -ve

35. 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)

36. The relationship between MSI status and cancer-specific survival P=0.042

37. CIMP study design • Extracted DNA requires bisulfite conversion • Followed by a methylight PCR assay for • CACNA1G • IGF2 • NEUROG1 • RUNX3 • SOCS1

38. DNA recovery following bisulfite treatment • DNA recovery following bisulfite treatment is variable and does not reach the projected > 75%

39. MSI and CIMP status as predictors of response to treatment

41. 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

42. 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])

43. 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

46. Conclusions • Colorectal cancer tumour heterogeneity exists • Techniques validated • MSI+/CIMP+ confers improved survival • Response to treatment remains unclear

47. Acknowledgments I would like to thank Dr David Batyand 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!

48. Thank you!