Laboratory diagnosis of cancer involves cytology, histopathology, and other techniques. Fine needle aspiration cytology (FNAC) is a simple, rapid, and economical technique to obtain cells for cancer diagnosis. It has high accuracy but loses tissue architecture. Histopathology examines diseased tissue microscopically and macroscopically. Cancer is graded based on cell differentiation and staged based on tumor size, lymph node involvement, and metastasis. Immunohistochemistry aids in cancer classification and detection of molecules with prognostic value.

1. Laboratory Diagnosis of Cancer
(FNAC & Histopathology)
DR. MD. SAIDUZZAMAN SAYID
MBBS, BCS (HEALTH)
LECTURER
DEPARTMENT OF PATHOLOGY
DINAJPUR MEDICAL COLLEGE,
BANGLADESH

2. Laboratory Diagnoses of Cancer
 Cytology
 Histopathology
 Immunohistochemistry
 Molecular and cytogenetic diagnosis
 Flow cytometry
 Tumour markers
 Electron microscopy

3. Cytology: Study of individual cells
 Fine needle aspiration cytology (FNAC)
Direct Image guided
 Exfoliative cytology
 Abrasive cytology

4. FNA consist of four coordinates steps
1. Palpation
2. Aspiration
3. Smear preparation
4. Fixation & Staining
5. Microscopy

5. FNAC with aspiration

6. PROCEDURE: EQUIPMENTS
1. NEEDLES: Routinely 22-23 gauge needle used.
2. Syringes: 5-10 ml syringe
3. Pistol handle

7. FAILURE TO OBTAIN A REPRESENTATIVE SAMPLE
 Needle has missed the target tangentially
 Needle in central cystic/necrotic/hemorrhagic area
devoid of diagnostic cells.
 Needle in dominant benign mass missing a small
adjacent malignant lesions.
 Fibrotic/desmoplastic target tissue giving a scant
cell yield.

8. PITFALLS OF FNAC
A. Deviation of needle
B. Poor aspiration technique
C. Poor smearing technique
D. Maintaining negative suction while with drawing
the needle.
E. Excessive suction
F. Forgetting to remove the stilette from the needle
G. Obtaining bloody aspirate.

9. FIXATIVES
 Fixatives commonly used 95% ethyl alcohol.

10. STAINS
 Smear stain by Papanicolaou stain.

11. ADVANTAGE OF FNAC
 Simple technique , no hospitalization is required
 Wide patient acceptance due to less trauma.
 Rapid diagnosis
 Economical
 Sampling from multiple sites in the same sitting
 High diagnostic accuracy
 Many techniques such as bacterial culture,
immunocytochemistry, flow cytometry, cytogenetics,
polymerase chain reaction, etc. are possible from FNAC
material.

12. DISADVANTAGE OF FNAC
 Loss of tissue architecture
 Capsular invasion and lymphovascular invasions
cannot be detected
 Difficult to differentiate in situ versus invasive
carcinoma
 Considerable training is needed for accurate
interpretation.
 May produces complications, e.g. Bleeding, infection.

13. FNAC Complications
 FNA is considered one of the safest invasive
diagnostic procedures though complications
were estimated at 0.03% of cases.
1)Hematomas
2)Infection
3)Pneumothorax

14. Contraindication
 Bleeding
 Obstructive
 Emphysema or pulmonary hypertention
 Pancreatitis
 Bacteraemia/septicemia

15. THE PRACTICE OF FNAC
 Success of FNAC depends on four fundamental
requirement:
1. Samples must be representative of the lesion investigated.
2. Samples must be adequate in terms of cells & other tissue
components
3. Samples must be correctly smeared and processed
4. FNAC must be accompanied by relevant and correct
clinical/radiological information.

16. Radiological aids in FNAC
 Plane X-ray film: for lesion in bone and for
lesions in the chests
 CT:for lesions in chest and abdomen
 USG guidance: which allows direct
visualization of needle placement in real time
and free from radiation hazards
 Image amplified fluoroscopy

18. Histopathology
 Histopathology: Gross & microscopic study
of diseased tissue.
 Biopsy: Removal of tissue from living body
for diagnostic purpose.
 Autopsy: Removal of tissue from dead body
to find out the cause of death.

19. Differentiation and Anaplasia
 Differentiation :
Refers to the extent to which neoplastic cells resemble
comparable normal cells, both morphologically and functionally.
 Anaplasia :
Lack of differentiation is called anaplasia.

20. GRADING
 The grade of a cancer is an assessment of its
degree of malignancy or aggressiveness.
 Grading is done on degree of differentiation of
the tumor cells (degree of resemblance to
normal counterparts).
 Classified as grades I to IV with increasing
anaplasia.

21. GRADING
 Grade I : More than 75% cell differentiation.
 Grade II : 50 to 75% cell differentiation.
 Grade III : 25 to 50% cell differentiation.
 Grade IV : Less than 25% cell differentiation.

22. STAGING
 Staging: Extent of spread of cancer
 Staging of cancer is based on:
1. Size of the primary lesion
2. Extent of spread to regional lymph node
3. The presence or absence of blood borne
metastasis

23. STAGING
TNM system:
TNM staging varies for specific forms of
cancer, but there are general principles.
 T for primary tumor
 N for regional lymph node
 M for metastases

24. STAGING
 With increasing size of primary tumor:
T1-T4, in situ-T0
N0 → No nodal involvement
N1 to N3- involvement of increasing number and
range of node
M0 → No distant metastases
M1 and M2-present of blood borne metastases
Grading of cancer has proved less clinical value than
staging.

25. IMMUNOHISTOCHEMISTRY
 Immunological method of recognizing a
cell, based on recognition of specific
components called “antigens”

26. IMMUNOHISTOCHEMISTRY: USES
 Categorization of undifferentiated malignant tumor
 Specific typing of leukemias/lymphomas.
 Determination of site of origin of a metastatic tumor.
 Detection of molecules that have prognostic & therapeutic
significance, e.g.,ER-PR receptors in carcinoma breast.
 Expression of protein products of oncogenes.
 Differentiating benign from malignant lesions.