1. The Interaction of Mutant B-RAF Protein and Expression of VEGF-C as Risk Factor for Regional Lymph Node Metastasis in Papillary Thyroid Carcinoma Dimyati Achmad, Johan S. Masjhur, Muchlis Ramli, Bethy S. Hernowo INDONESIA

2. Papillary Thyroid Carcinoma (PTC) Is one of the least morbid solid carcinoma Slow growing tumor Favorable long-term survival But Approximately 33% to 61% of PTC will have involvement of cervical lymph nodes at the time of diagnosis

3. The regional lymph node metastasis in PTC appear no correlation with overall survival but consistenly correlate with local or regional reccurence. Until now, molecular pathogenesis of lymph node metastasis in PTC is still controversial.

4. Under this circumstances, we would like to emphasis on the risk factor that plays an important role in the migration and invasion of PTC cells to extra thyroidal structure, which is related to mutant B-RAF protein and also VEGF-C expression in lymphangiogenesis process.

5. The aim of this study is to prove the existence of interaction between mutant B-RAF protein and VEGF-C expression, as the risk factor of lymph node metastasis in PTC.

6. This study is: Case – control study Comparative observation between: – 38 subjects PTC with LN. metastases – 38 subjects PTC without LN. metastases as a control group, selected by matching process.

7. The Independent Variable – Mutant B-RAF protein – VEGF-C expression The Dependent Variable – Regional lymph node metastasis

8. The mutant B-RAF protein and VEGF-C expression were identified by immunohistochemistry examination. And the result define by histoscore: based on McCarty Criteria (1995). Highest intensity50 – 80% distribution

9. The Analysis: We analyzed data by : The McNemar bivariant analysis test For compare each independent variable with dependent variable The double logistic regression multivariant analysis test and the stratification analysis test For compare two independent variable with dependent variable

10. The Associaton Between Mutant B-RAF Protein and LN. Metastasis in PTC The result showed an evidence significant association (p < 0.05) Mutant B-RAF Protein Case n = 38 Control n = 38 p. Value Positive 32 (84.2%)18 (47.4%) 0.023 Negative 6 (15.8%)20 (52.6%) Mc Nemar test OR: 5.92 (95% CI: 2.01 – 17.45)Results:

11. The Associaton Between VEGF-C Expression and LN. Metastasis in PTC The result showed unrelated association (p > 0.05) VEGF-C Expression Case n = 38 Control n = 38 p. Value Positive 33 (86.8%)30 (78.9%) 0.272 Negative 5 (13.2%)8 (21.1%) Mc Nemar test OR: 1.76 (95% CI: 0.51 – 5.97)

12. An Interaction Between Mutant B-RAF Protein and VEGF-C Expression as Risk Factor of LN Metastasis in PTC The multivariant analysis test Showed: a significant result p = 0.001, OR 5.92 (95% CI: 2.01 – 17.44) The stratification analysis test Showed: a significant result p = 0.004, OR 6.44 (95% CI: 1.23 – 33.80)

13. Summary MAPK Mutant B-RAF Protein PTC Cell

14. Conclusions : Molecular Pathogenesis Lymph node metastesis in PTC occurs due to interaction between two processes: Invasion of PTC cell to Extrathyroidal Structure and Lymphangiogenesis process. The interaction between mutant B-RAF protein and VEGF-C expression, has a role as a dominant risk factor of lymph node metastasis in PTC.

15. Thank You

18. Summary of Significant Differences Mutant B-raf Initiation of MAPK pathway occur through Central Protein Activation HIF1α occur through two mechanisms Hypoxia Condition and Crosstalk between ERK and HIF1α Shorter Process Non-Mutant B-raf Initiation of MAPK pathway occur through Thyrocinekinase receptor Activation HIF1α occur through hypoxia condition Longer Process No crosstalk

19. Summary