Fig. 2
From: Primary thyroid gland myxofibrosarcoma: a case report and review of the literature
Histomorphology and immunohistochemistry of high-grade MFS of the thyroid gland. a MFS of the thyroid gland presenting as multi-nodular tumor composed of pleomorphic spindle-shaped cells infiltrating the normal thyroid parenchyma with vascular invasion (hematoxylin–eosin staining (HE), ×25). b Higher magnification demonstrates a myxoid stroma arranged along curvilinear blood vessels (HE, ×50). c Immunohistochemical staining showing strong expression of CD99 in myxoid (left) and more densely packed (right) tumor areas, while remnant thyroid follicles (arrows) stain negative for CD99 (×50). d Remnant thyroid follicles (upper right) exhibit a strong nuclear expression of TTF-1, while surrounding tumor cells remain negative (50x)