Calcification and Expression of Bone Morphogenetic Protein-4 in Papillary Thyroid Carcinoma

Background/Aim: The purpose of this study was to investigate whether bone morphogenetic protein (BMP)-4 expression differs according to the presence of calcification in papillary thyroid carcinoma and to investigate if calcification and BMP-4 expression are associated with metastasis of papillary carcinoma.Methods: We performed the study using paraffin-embedded tissues of 55 patients who underwent thyroidectomy in Kosin University Gospel Hospital. Of those 55 cases, 36 were papillary thyroid carcinomas, and 19 were benign tumors. Immunohistochemical staining with BMP4 antibody was performed on the paraffin-embedded tissues.Results: Among the 36 papillary thyroid carcinomas, 20 (55.6%) of extrathyroidal invasion and 21 (58.3%) of lymph node metastasis were observed. The presence of calcification was significantly different according to incidence of extranodal invasion (p = 0.02), lymphovascular invasion (p < 0.001), and lymph node metastasis (p = 0.04). BMP-4 expression was weakly positive in benign tumors and strongly positive in papillary thyroid carcinoma (p < 0.001). BMP-4 expression was significantly different by TNM stage (p < 0.001).Conclusion: In the present study, the presence of calcification in thyroid papillary carcinoma was associated with tumor metastasis. BMP-4 was strongly expressed in papillary thyroid carcinoma and was associated with the stage of papillary thyroid carcinoma.