Lab diagnosis cancer

Laboratory diagnosis cancer

1. LABORATORY DIAGNOSIS OF CANCER Dr Utkarsh Sharma

2. Common techniques of cancer diagnosis Radiological diagnosis Cytological diagnosis Histological diagnosis Frozen section H ae matogical diagnosis Immunohistochemistry Molecular diagnosis Tumour marker s

3. 1.RADIOLOGICAL DIAGNOSIS It include s X-ray Ultrasound CT scan MRI These are one of the best non invasive techniques for early diagnosis of cancer.

4. 2.CYTOLOGICAL DIAGNOSIS

5. 1. Fine needle aspiration cytology (FNAC) Fine needle aspiration cytology is a popular method of tumor diagnosis particularly for palpable tumors Lymph nodal tumors Breast tumors Salivary gland tumors Thyroid tumors Liver SOL

6. 3.HISTOLOGICAL DIAGNOSIS : For histological diagnosis the following methods of sampling is done: Biopsy - biopsy is a surgical removal of small piece of tissue f or microscopic examination for the presence of cancer cell. There are three ways tissues can be removed for Biopsy:- Endoscopy Needle biopsy Surgical biopsy

7. Endoscopy- in this process , a thin, flexible tube with a tiny camera on the end is inserted into the body cavity. This allows the doctor to view the abnormal area. Needle biopsy - the doctor takes a small tissue sample by i nserting a needle into abnormal area. Different types of needles are used, E x : Vim Silverman needle for liver biopsy . Renal biopsy needle for renal tissue . True cut biopsy needle for prostatic t issue or breast tissue . Surgical Biopsy:- There are two types of surgical biopsies. An excisional biopsy : it is performed when the doctor removes the entire tumor, often with some surrounding normal tissue.

8. An incisional biopsy : it is performed when the doctor removes just a portion of the tumor. If cancer is found to be present, the entire tumor may be removed immediately or during another operation. The processing of tissue and its diagnosis takes a two or three days.

9. 4. FROZEN SECTION:- Frozen section is quick diagnosis method. The tissue is quickly frozen at around - 20 C in frozen section cryostat which makes the tissue hard . - tissue is immediately sectioned & stained -the whole process from receiving, staining to diagnosis can be completed within 10 to 15 days.

10. 5. HAEMATOLOGICAL DIAGNOSIS:- Complete blood count (CBC) Peripheral blood film (PBF) Bone marrow aspiration Bone marrow imprint smear Bone marrow biopsy. Important in diagnosis of leukemia.

11. Flow cytometry Flow cytometry is a technique used to detect and measure physical and chemical characteristics of a population of cells or particles. A sample containing cells or particles is suspended in a fluid and injected into the flow cytometer instrument. The sample is focused to ideally flow one cell at a time through a laser beam and the light scattered is characteristic to the cells and their components. Cells are often labeled with fluorescent markers so that light is first absorbed and then emitted in a band of wavelengths. Tens of thousands of cells can be quickly examined and the data gathered are processed by a computer.

12. 6.

13. 7.MOLECULER DIAGNOSIS Molecular diagnostics is a collection of techniques used to analyse biological markers in the genome and proteome—the individual's genetic code and how their cells express their genes as proteins by applying molecular biology to medical testing .

14. Allele-Specific PCR Variants detected :  Typically considered targeted analysis for the detection of a specific single nucleotide variant (SNV). Time to complete test:  1–2 days. Pros:  Sensitive—can detect mutant DNA if present at 1–5%. No special equipment required. Cons:  Target specific and cannot detect other mutations that may be present in tumor DNA.

15. Sanger Dideoxy Sequencing Variants detected: Unknown mutations including SNVs and small duplications, insertions, deletions, and indels of interest . Pros: A variety of unknown mutations can be detected. Can be used to detect gene fusions if RNA from the fusion transcript is first extracted from the specimen. No special equipment required. Cons:  Labor intensive and requires mutant DNA to be present at 20–25%. Cannot detect changes in exon or gene copy number.

16. Pyrosequencing Variants detected: Unknown mutations in a small targeted region . Time to complete test:  2–3 days. Pros:  Quick and sensitive detection of mutant DNA at a level of 5%. Cons:  Requires pyrosequencing instrumentation; is limited in the types of mutations that can be detected in tumor DNA.

17. Mass Spectrometry – MS Variants detected:  Targeted SNVs . Time to complete test:  2–3 days. Pros:  Sensitive, reliably detecting mutant DNA if present at 5–10%; tests more than one gene. Cons:  Requires mass spectrometry instrumentation; SNV-specific and cannot detect other mutations in tumor DNA that may be present.

18. Multiplex Ligation-Dependent Probe Amplification – MLPA Variants detected:  Exon and gene copy number. Depending on experimental design, can also detect SNVs . Pros:  Quick and able to detect multiple mutations  simultaneously. Can detect targeted SNVs at 10%. Cons:  For exon or gene copy number variant detection, requires mutant DNA to be present at levels of 20–40%. Testing works better on fresh frozen tissue than on DNA extracted from paraffin-embedded tissue.

19. Fluorescence In Situ Hybridization Variants detected :  Targeted gene copy number changes and targeted SVs. Method:  Fluorescent probes are used to locate genes or sequences of interest on one or more chromosome. Fluorescence microscopy is used for detection. Time to complete test:  2–3 days. Pros:  Easily detects gene copy number changes and targeted SVs that are not as easily detected by other methods; cell-based imaging enables detection of events in a small fraction of cells. Cons:  Requires paraffin-embedded tissue on unstained slides; cannot detect most types of mutations occurring in solid tumor neoplasms. 

20. Next Generation Sequencing- NGS A sequencing method where millions of sequencing reactions are carried out in parallel, increasing the sequencing throughput . Pros:  Enables simultaneous detection of single base substitutions as well as more complex mutations including duplications, insertions, deletions, and indels in many genes in a single assay; requires low inputs of DNA . Cons: Expensive

21. 8. TUMOR MARKER: - So m e tumo r s r elease certain su b s t ance s c al l ed tum o r markers . Blood test can be performed to detect the blood c ells as well as for specific tumor markers . Tumor marker is biochemical indicators of t umors , these may be: Antigens Cytoplasmic proteins Enzymes Hormones Use d in support diagnosis

22. Liquid biopsy Tumors almost always shed some amount of their fragments into peritumoral space. These fragments may be represented by single malignant cells or their clusters as well as by various proteins, nucleic acids, small molecules, etc. Consequently , these entities can be collected in various body fluids (serum, saliva, urine, etc.) and serve as tumor markers.