The association between integrin β4 overexpression and lymphovascular invasion in papillary thyroid cancer.

Introduction: Lymphovascular invasion is an independent prognostic marker in papillary thyroid carcinomas. In addition, integrin β4 is associated with advanced progression and metastasis in many malignancies. We aimed to investigate the relationship between integrin β4 and lymphovascular invasion in papillary thyroid carcinoma.

Material and methods: 73 patients with papillary thyroid cancer (48 patients with lymphovascular invasion and 25 patients without) were included in our study. The immunohistochemical staining score for integrin b4 was evaluated according to the percentage and intensity of staining. The staining intensity was scored as 0 (no staining), 1 (weak staining - light yellow), 2 (medium staining - yellow-brown), and 3 (strong staining - brown). The staining was scored by multiplying the percentage and intensity of staining.

Results: The mean percentage of integrin b4 staining was 63.54 ± 22.26% in the group with lymphovascular invasion and 10.2 ± 22.48% in the group without lymphovascular invasion (p < 0.001). When evaluated in terms of staining score, it was found to be 107.08 ± 45.29 in the group with lymphovascular invasion and 16.2 ± 40.03 in the group without lymphovascular invasion (p < 0.001). There was a linear relationship between the percentage of integrin β4 and the staining scores (r² = 0.881; p < 0.001). In the by receiver-operating characteristic (ROC) curve analysis for the cut-off value of the percentage of integrin b4 staining, the area under the curve was found to be 0.916. The cut-off value for the percentage of integrin b4 was found to be 35 (sensitivity 91.7% and specificity 88%) (odds 80.66%).

Conclusions: A significant relationship was found between integrin b4 expression and lymphovascular invasion in papillary thyroid carcinomas. Integrin b4 expression level can be used as a marker to predict the presence of lymphovascular invasion in papillary thyroid carcinomas, especially in large tumours where it may not be possible to sample the entire tumour.