Primary leiomyosarcoma of the thyroid gland with prior malignancy and radiotherapy: A case report and review of literature

Figure 1 The tumor cells tested positive for alpha smooth muscle actin, calponin, H-caldesmon, but were negative for CD34, p53, estrogen receptor, progesterone receptor, and Epstein-Barr virus. In approximately 25% of all the tumor cells, the Ki67 proliferative index was positive. A: Pathological finding of thyroid gland stained (10 ×); B: Positive immunohistochemical staining for α-smooth muscle actin (10 ×); C: Negative immunohistochemical staining for P53 (20 ×); D: Pathological finding of 25% positive Ki67 index in tumor cells (20 ×); E: Negative immunohistochemical staining for CD34 (10 ×); F: Positive immunohistochemical staining for calponin (20 ×).