Molecular biology in surgical diagnosis and therapy

1. Dr. Suprava Biswal
PG – 1,
Dept of Surgery,
IMS SUM
Molecular Biology In Surgical
Diagnosis and Therapy

2. Specific Learning Objectives
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Need of Molecular Diagnostics in Surgery
Specimen used for Molecular Diagnostics
Diagnostic modalities
Management of Surgical cases by Molecular methods

3. What is Molecular Biology
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4. Interest to Surgeons
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 Diagnosis
 For conclusive clinical diagnosis
 Accidental and incidental findings
 Differentiating benign from malignant
 Classification of cancer
 Cancer screening programs
 Staging of detected malignancies
 Management of patients
 Selection of treatment modality
 Assessing treatment response
 Prognostic evaluation

5. Tissue Specimens
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 Histology
 Formalin Fixed
 Biopsy
 Resection
 Fresh Tissue
 Frozen Section
 Research – Tissue banking
 Cytology
 Cervical
 Scrapes & washing
 FNAC
 Liquid Biopsy

6. Tissue Specimen (contd.)
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 Specimens are either by biopsy or resection
 USG or CT – guided biopsies aid in reducing errors
 Collected sample is used for molecular analysis
 For routine histology – immediately fixed with formalin by the surgical team
 For frozen section – done intraoperatively
 Cytology specimens – collected directly (urine, sputum) or through washing (Bronchial lavage) or FNAC

7. Tissue Preparation
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8. Diagnostic modalities
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9. Diagnostic modalities
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 Immunohistochemistry (IHC)
 Detects specific dye-labelled antigen
 Quantifiable
 Safe, quick and inexpensive
 Both fixed and frozen tissue can be used

10. Diagnostic modalities (contd.)
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11. Diagnostic modalities (contd.)
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 Polymerase Chain Reaction
 Amplifies DNA to check for genetic
abnormalities
 Mutational Analysis testing for
clonality,
 detection of fusion transcripts
resulting from cytogenetic
changes,
 Detection of amplifications,
 and detection of gene
hypermethylation

12. Diagnostic modalities (contd.)
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Genes Associated with specific Cancers

13. Diagnostic modalities (contd.)
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 Fluorescent In-Situ Hybridization
 Easy to use and common technique for detection of genetic
abnormalities
 Fluorescent labelled oligonucleotide probe
 that targets a specific sequence of RNA or DNA
 allows visualization of the presence or absence and location of
a particular RNA or DNA sequence in situ in tissue section
 visualized by fluorescence microscopy

14. Diagnostic modalities (contd.)
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HER2 pattern in FISH
EWSR1 pattern in FISH

15. Diagnostic modalities (contd.)
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 Other sequencing techniques
 Next Generation Sequencing
(NGS)
 Detects genomic
abnormalities
 Associated with
carcinomatous changes

16. Management of Surgical cases by Molecular methods
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 Management aimed in 2 parts
 Treatment by Precision Medicine
 Prognostic assessment

17. Management of Surgical cases by Molecular methods
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 Cancer Precision Medicine
 development of individualized cancer care
plans,
 partly on the basis of molecular
abnormalities in a tumor
 Germline and somatic mutations may be
taken into consideration

18. Management of Surgical cases by Molecular methods (contd.)
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Targeted therapeutics for GI Cancer Targeted therapeutics for Breast Cancer

19. Management of Surgical cases by Molecular methods (contd.)
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 Cancer Prognosis
 determine the selection of therapy for
tumors may also have additional prognostic
value

20. Management of Surgical cases by Molecular methods (contd.)
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Molecular Diagnostic and Therapeutic Profiling of Common Carcinomas

21. Thank You!