A New MEN2 Syndrome with Clinical Features of Both MEN2A and MEN2B Associated with a New RET Germline Deletion

Figure 2

Histology of MTC and other lesions. Panels A and A₁: MTC hematoxylin/eosin staining, magnification 2X and 10X, respectively. Panels A₂ and A₃: positive anticalcitonin immunostaining (10X) and negative antithyroglobulin immunostaining (10X) confirming the diagnosis of MTC. Panels B and B₁: MTC infiltrating the perithyroid gangliar tissue, as indicated by the arrows (panel B, 2X, panel B1, 4X). Panel C: MTC vascular invasion with a neoplastic embolus (4X). Panel D: central compartment lymph node metastasis (2X). Panel E: hematoxylin/eosin staining of ganglioneuromatosis in the mucosal neuromas of the mouth excised during surgery (2X). Panel F₁: low-power view of the pelvic plexiform neurofibroma. Panel F₂: at higher power, the neurofibroma component consists of a uniform population of bland spindle cells with wavy elongated nuclei set in a fibrillary matrix. Panel F₃: the ganglioneuromatosis elements, which consist of large ganglion-like neurons.