Metastatic Papillary Thyroid Carcinoma with Multifocal Synchronous Transformation to Anaplastic Thyroid Carcinoma

Figure 4

(a) 20x: Napsin-A immunohistochemical stain depicting a focus of diffuse cytoplasmic staining. (b) 20x: thyroglobulin immunohistochemical stain which is negative in the tumor.

(a)

(b)