Association of clinicopathological type in carcinoma of the neck showing thymus-like elements

Objective To study the clinicopathological type, histogenesis and differential diagnosis of carcinoma of the neck showing thymus-like elements (CASTLE) . Methods With clinical and pathological data of benign and malignant thymus-like differentiation of thyroid cancer cases occur in the soft tissues of the neck, thyroid tissue, immunohistochemical detection applications, combined with literature data, analysis of benign and malignant thymus-like differentiation of thyroid cancer clinical pathological type relationship with histopathological diagnosis. Results Three cases of thymuslike differentiation of thyroid cancer, thyroid tissue, respectively, outside. The clinical symptoms of anterior neck mass, hoarseness. Tumor size, for example 1: 4.0 cm×2.5 cm×1.5 cm, capsule, solid, encapsulated. Example 2: 1.0 cm×1.0 cm×0.8 cm, less clear boundaries. Example 3: 7.0 cm×5.0 cm×4.5 cm, gray cut fish-like. Microscopy: benign thymus-like organization performance cyst-like structures, see remnants of branchial sac blastocyst-like tissue between the wall, the thymus like tissue and papillary hyperplasia tissue, the shape of tiny thyroid papillary cancer. Island shape vicious thymus-like tissue in the thyroid gland, nested distribution, inter-island fiber separated tumor cells spindle, fit, the part see see thymuslike structures, interstitial infiltration of lymphocytes, the shape of medullary thyroid carcinoma. Part of the vicious thymuslike tissue invasive growth inside and outside the thyroid tissue, the shape of the thyroid squamous cell carcinoma. Immunohistochemistry: CD5, CD117, CK19,TTF-1 positive, P63, CK18, CK7, CK, Syn, some positive, CEA, the EMA, the Tg, S-100, CgA, Vim, negative, Ki67 (<5%) . Conclusions Thymus-like differentiation of thyroid cancer, a class can occur in the thyroid tissue, can be seen in the extrathyroidal soft tissue around the rare, the morphological features of mediastinal thymic carcinoma of thyroid malignancies. Histological structure more performance for thyroid squamous cell carcinoma, medullary thyroid carcinoma and thyroid carcinoma lymph on. Thymic cyst structure for a small part of the morphological appearance of the tumor tissue, accompanied by a small papillary structures, the shape of the thyroid micro papillary carcinoma, tumor adjacent tissues visible remnants of thymuslike tissue and the branchial cleft blastocystlike tissue, mostly relicts of these organizations, the epitheliallike tissue differentiation and the formation of papillary structures, and then developed into a "tiny thyroid papillary carcinoma. May be suggestive of a "thymus-like differentiation of thyroid micro papillary carcinoma". Binding site, histopathological features, immunohistochemical CD5, CD117, TTF-1, CK19 detection useful in differential diagnosis. Key words: Neck thyroid thymuslike tissue differentiation; Clinicopathological type; Immunohistochemistry; Differential diagnosis