Biomarkers in Anatomic Pathology Adding Value in Diagnostics

1. Biomarkers in Anatomic PathologyAdding Value in Diagnostics Jennifer Hunt, MD, MEd, FCAP

2. Biomarkers in Anatomic Pathology: Adding Value in Diagnostics Jennifer L. Hunt, M.D., M.Ed. Section Head, Surgical Pathology Director, Head and Neck and Endocrine Pathology Director, Molecular Anatomic Pathology Unit

5. Auguste Nélaton (1807 – 1873) “The microscope is not, for the biologist or physician, an instrument which he can indifferently make use of; its employment is absolutely necessary. Accustomed to judge from exterior characters alone, pathologists should not be astonished that many results obtained by them are shown to be inexact or incomplete by the microscope. Far from believing that the fault comes from the new information added by the microscope, it is the history of diseases which must be taken up again and revised, starting from the new and much more precise notions of the tissue furnished by microscopy.”

6. Rudolph Virchow (1821-1902): Father of Microscopic Pathology Zaccharias Janssen (1590-1608): First Microscope Anton van Leeuwenhoek (1632-1723): Bacteria Robert Hooke (1635-1703) Father of Microscopy Carl Rokitansky (1804-1878): Father of Autopsy Pathology 1800 1600 1700 1900

7. Peyton Rous (1910): Oncogenes (Nobel Prize 1966) Kary Mullis (1983): Polymerase Chain Reaction (Nobel Prize, 1993) Ernst Ruska & Max Knott (1931): Electron Microscope (Nobel Prize, 1986) Frederick Sanger (1975): Sequencing (Nobel Prize, 1980) Watson & Crick (1953): DNA (Nobel Prize, 1962) Alfred Knudson (1971): Tumor suppressor genes (Lasker Award, 1998) Sternberger (1978): Immuno-cytochemistry 1950 1960 1970 1980 1990 2000

8. Gross Exam (1500-1800) Microscopic Analysis (1800-1930) Electron Microscopy (1930-1980) IHC (1980-2000) DNA (2000) MicroRNA

9. Agenda: Biomarkers in AP • The Past: Diagnosis • The Present: Prognosis • The Future: Therapeutics 1800 Diagnostic Assay Era 1960 Prognostic Assay Era 2000 Therapeutic Assay Era

10. Biomarkers

11. Biomarkers: Definition • “A specific physical trait or measurable biologically produced change in the body connected with a disease or health condition” • Any marker of biological status

12. Biomarkers: Examples

13. Drivers of Biomarker Testing • Understanding pathogenesis • Better diagnosis • Better prognostic information • Better understanding of therapeutic response

14. Biomarkers in Pathology • The Past: Diagnosis • The Recent Past: Simple Prognosis • The Present • Advanced Prognosis • Understanding Biology • The Future: Therapeutics Colon Cancer

15. Colon Cancer Diagnostics • 1700’s: Gross diagnosis • 1800’s: Microscopic diagnosis

16. Abdominal mass with cachexia and bowel symptoms • Abdominal mass and histologic identification of tumor • Gradual bowel symptoms, cachexia, stricture symptoms, and histologic identification of tumor Einhorn M, 1900

17. Gross Exam (1500-1800) Microscopic Analysis (1800-1930) Electron Microscopy (1930-1980) IHC (1980-2000) DNA (2000) MicroRNA

18. Biomarkers in Pathology • The Past: Diagnosis • The Recent Past: Simple Prognosis • The Present • Advanced Prognosis • Understanding Biology • The Future: Therapeutics

19. Colon Cancer Anatomic Prognosis • 1932: Dukes Staging System (rectal) • 1953: Astler-Coller modification of Dukes • 1965: AJCC Staging System

20. Colon Cancer Biology & Prognosis • 1990-1993: Genetics of familial adenomatous polyposis (FAP) • 1991: APC locus identified • 1993: APC gene cloned • 1993: Genetics of hereditary non-polyposis colorectal carcinoma (HNPCC) • Microsatellite instability identified

21. Genetic of Colon Cancer Tumor Suppressor Gene (85%) Microsatellite unstable cases (15%) 15% 5% HNPCC

22. Genetics of Colon Cancer

23. Gross Exam (1500-1800) Microscopic Analysis (1800-1930) Electron Microscopy (1930-1980) IHC (1980-2000) DNA (2000) MicroRNA

24. Biomarkers in Pathology • The Past: Diagnosis • The Recent Past: Simple Prognosis • The Present • Advanced Prognosis • Understanding Biology • The Future: Therapeutics

25. Approved Targeted Therapies

26. Response Cost Side Effects Success of Targeted Therapy

27. Cost Per Month • Gleevec: $3,000 • Herceptin: $2,800 • Rituxan: $12,000 • Iressa: $1,800 • Tarceva: $2,700 • Erbitux: $9,600 • Vectibix: $8,000 75% of personal bankruptcy is caused by a catastrophic illness Himmelstein DU. 24(1),2005

28. Future: Biomarkers for Therapeutics • Selection for therapeutics • Companion diagnostics • Monitoring of therapeutic response • Minimal residual disease testing • Predicting resistance to therapeutics • Markers of tumor resistance

29. PROLIFERATION APOPTOSIS ANGIOGENESIS Courtesy of Dr. S. Dacic EGFR Extracellular Domain Transmembrane Domain TRANSMEMBRANE CELL MEMBRANE Cytoplasmic Domain

30. Epidermal Growth Factor Receptor • Altered in many tumors • Protein Expression • Gene copy number • Gene sequence

31. Epidermal Growth Factor Receptor • Blockade of EGFR pathway • Monoclonal antibody • Small molecule inhibitors of tyrosine kinase

32. Monoclonal Ab (Erbitux) Small molecule inhibitors (Iressa, Tarceva)

33. Colon Cancer Therapeutics • 2004: EGFR Pathway in colon cancer • Erbitux approved by FDA for colon cancer treatment • EGFR antibody approved by FDA • 2008: Predictors of resistance • KRAS mutations insensitivity to Erbitux

34. June, 2008 March, 2009 Early 2005 December, 2001 October, 2007 February, 2004 ASCO data: KRAS Mutation Completion of CA225006 FDA negative report • FDA Approval • Erbitux • EGFR PharmDx Literature against EGFR IHC testing Anticipated Completion of CA225014 Erbitux Timeline

35. Challenges for Pathology • Biomarker selection • Testing • Assay development • Validation • Interpretation • Operational impediments • Patents • Cost and reimbursement Pathologist Training

36. Who Validates New Assays? • Laboratory technical staff • Anatomic pathologists • Molecular pathologists

37. Predicted Labor Shortage by 2020 Number of people Estimated Labor Shortage by 2020 Auerbach, D. Health Affairs. 26(1), 2007:178 AAMC Study on Physician Shortage, August 2007 Castleberry BM, Lab Med 30, 1999: 174

38. Molecular Genetic Pathology Fellowships Absolute Number Source http://www.acgme.org/adspublic/ Accessed March 22, 2008

39. Who Signs Out Results? • Send-out laboratories • Anatomic pathologists • Molecular pathologists

40. AMP Test Directory • Microsatellite instability: 11 laboratories • EGFR: 5 laboratories • K-RAS: 4 laboratories http://www.amptestdirectory.org/ Accessed 6/2/2008

41. Training of Pathologists Data courtesy of CAP June, 2008

42. Hybrid capture for HPV (1995) Quantitative PCR (1992) PCR (1983) IHC (1978) Sequencing (1975)

43. Number of MGP Applicants End of Grand-father Period Absolute Number Source: https://www.abpath.org Accessed 3/23/2008

44. Challenges for Pathology • Biomarker selection • Testing • Assay development • Validation • Interpretation • Operational impediments • Patents • Cost and reimbursement

45. Gross Analysis Microscopic Analysis Electron Microscopy Immunohisto-chemistry DNA MicroRNA

46. Auguste Nelaton (1807 – 1873)(Modified for 2008) “Biomarker testing “The microscope is not, for the biologist or physician, an instrument which he can indifferently make use of; its employment is absolutely necessary. Accustomed to judge from exterior characters alone, pathologists should not be astonished that many results obtained by them are shown to be inexact or incomplete by the microscope. Far from believing that the fault comes from the new information added by the microscope, it is the history of diseases which must be taken up again and revised, starting from the new and much more precise notions of the tissue furnished by microscopy.” (s)he the microscopic appearance, biomarkers. biomarkers, biomarkers.”