Immunohistochemistry and fluorescent in situ hybridization are techniques that help identify the primary site of metastatic cancers and define disease subtypes through detection of protein markers and genetic translocations. Both techniques guide therapy decisions and provide prognostic information. Immunohistochemistry works similarly to ELISA by detecting antibodies bound to tumor cell antigens, while fluorescent in situ hybridization uses fluorescent DNA probes to detect genetic abnormalities. Flow cytometry also analyzes cellular markers like CD34, CD10 and CD19 to diagnose cancers such as acute lymphoblastic leukemia and monitor minimal residual disease following treatment.

1. Newer techniques

2. Immunohistochemistry

3. Case Scenario
Metastatic disease …. Where is the
primary malignancy ?

4. IHC on Lymph node … metastatic
cells positive for CDX2
Primary is in the colon

5. How is immunohistochemistry done ?

6. Principle is similar to ELISA

7. IHC guides therapy

8. IHC helps grade a tumor
Good ….….. Bad …….…Ugly

9. Help pick up organisms

10. Fluorescent in situ hybridisation

11. Case scenario

12. FISH helps identify disease
defining translocations

13. Principle of FISH

14. FISH also guides therapy

15. Flow cytometry

16. Case scenario

17. CD34, CD10, CD19
Acute lymphoblastic leukemia

18. Principle of flow cytometry

19. Technical part

20. Sort stem cells for transplantation

21. Assess minimal residual
disease in acute leukemia

22. Summarise

23. Questions ?