prensentation on lab diagnossis of neoplasia for medical students.

1. LAB DIAGNOSIS OF NEOPLASIA
PRESENTED BY:
MADHUR KUMAR SEJWAL

2. VARIOUS METHODS OF DIAGNOSIS
a. Cytological and Histopathological techniques
b. Immunocytochemistry & immunohistochemistry
c. Molecular Diagnosis
d. Flow cytometry
e. Tumour markers

3. A) MORPHOLOGICAL METHODS
i. FNAC
ii. Exfoliative cytology
iii. Abrasive cytology
iv. Washings and lavage Techniques

4. I) FNAC

5. II) EXFOLIATIVE CYTOLOGY
Tumour cells are less cohesive, hence are shed from lining epithelium
to body cavities, collected and studied.
Examples: vaginal, cervical smears
urine containing cells from
GU
sputum
effusions in the body

7. III) ABRASIVE CYTOLOGY
Surface scraped using Ayre’s Spatula or brush.
With or without optic guidance
Examples: cervical smears (PAP smear)
bronchoscopic brushings
endoscopic brushings from
lesions of GIT

8. IV) WASHINGS AND LAVAGE
• Normal saline is instilled into body cavity and reaspirated back,
collecting shed cells
Examples: gastric lavage, peritoneal
lavage, bladder lavage
 Fixative used: 95% ethylalcohol or cytospray
 Stains used: Papanicolaou stain or Giemsa stain

9. ADVANTAGES OF CYTOLOGY
• Rapid
• No hospitalization
• Minimally invasive
• Rapid, accurate diagnosis in expertise hands
Disadvantage of cytology:
• Small sample size and sampling errors
• Cannot comment on architecture and invasion

10. HISTOPATHOLOGY

11. Fixative used: 10% neutral Formalin
Various steps:
1. Fixation
2. Dehydration
3. Clearing
4. Impregnation
5. Staining
6. Examination of slide

12. FROZEN SECTION
Cryostat used
Liquid N at -190 C or liquid carbon dioxide at -90 C used to freeze IC water
into ice (embedding medium)
Used for:
 Rapid ‘on-table’ diagnosis
 Preservation of enzymes and labile substances like lipids and glycogen
 Determining nature of mass lesion

13. B) IHC AND ICC

14. USES:
1. Diagnosis of undifferentiated neoplasms.
o (+) cytokeratins & mucins carcinoma
o (+) desmin & vimentin sarcoma
o (+) CD antigen lymphoma
2. Detection of site of origin of metastatic tumours.
o Detect tissue specific or organ specific ag in a biopsy specien of the
metastatic deposit e.g: PSA, CEA, thyroglobulin

15. 3. Detection of molecules that have therapeutic or prognostic significance
o ER/PR on cells of ca.breast
4. For categorisation of lymphomas and leukemias

16. C) MOLECULAR TECHNIQUES
F.I.S.H
PCR
Gene chip method

17. • F.I.S.H
DNA probe of known complementary receptors couple with fluorescent
dye and applied to nucleus. The specific sequences bind to the
complementary DNA

18. • PCR

19. • GENE CHIP METHOD
They are gene scanning techniques,
based on oligonucleotide arrays called
DNA chips, that provide a rapid method
to analyze thousands of genes
simultaneously

20. USES
1. Diagnosis of malignancy- PCR based detection
of BCR-ABL gene provides molecular diagnosis of CML.
2. Categorisation of leukemias &
lymphomas- PCR based detection of TCR allows
distinction between monoclonal(neoplastic) and polyclonal( rxctive)
proliferations.

21. 3. Prognosis and behaviour- FISH and PCR methods
can be used to dectect amplification of oncogenes such as HER2/NEU
in ca.breast – bad prognosis.
4. Detection of minimal residual disease-detection
of BCR-ABL transcripts give measure of residual disease in
patients treated for CML.
5. Diagnosis of hereditary predisposition-
Primary realtives are screened for germ-line mutations to allow for an
opportunity for prophylactic surgery and genetic counselling e.g:
BRCA1 in ca.breast.

22. D) FLOW CYTOMETRY
Rapidly and quantitatively measure individual cell characteristics (e.g
membrane antigens, DNA content of tumour cells)
Useful in identification and classification of lymphomas and leukemias
To detect aneuploidy that carries bad prognosis.

23. E) TUMOUR MARKERS
Biochemical assays for tumour-associate enzymes, hormones, oncofetal
antigens, proteins, mucins or molecular markers.
Indicators for the presence of tumours.
Useful in determining the effectiveness of therapy or detecting any
recurrence.

26. Tumour markers have only a PROGNOSTIC
value.
Importance:
i. Pre-op:
a)To support diagnosis
b)Help assess tumour load
ii.Post-op:
a) efficacy of treatment. Whether there is
any residual disease.

27. REFERENCES:
Class notes
Robbins BASIC PATHOLOGY.