title: Follicular carcinoma of the thyroid with extensive clear-cell differentiation: a potential diagnostic pitfall.
abstract: Clear-cell features have been recognized in several different thyroid neoplasms. A case of thyroid follicular carcinoma with extensive clear- and Hurthle-cell features is described in a 37-yr-old white female, with cytochemical and immunohistochemical analysis. The tumor of the thyroid gland, with anterior neck soft-tissue extension, displayed clear cells on fine-needle aspiration, which were negative for thyroglobulin. The surgical specimen displayed predominately clear cells (80%), and only the nonclear-cell areas stained for thyroblobulin. Proper categorization of clear-cell lesions of the thyroid and soft tissues requires a multimodality approach, involving clinical/pathological correlation, morphological analysis, and ancillary tissue studies. Immunohistochemical stains for thyroglobulin are quite definitive in making the distinction between primary clear-cell thyroid tumors vs. metastatic clear-cell tumors. Cytologists should be aware, however, that the clear-cell areas of thyroid tumors might not stain for thyroglobulin.
authors.affiliation: Department of Pathology, Anatomy, and Cell Biology, Thomas Jefferson University Hospital, Philadelphia, Pennsylvania 19107, USA. ropp@martnet.com
authors.forename: B G
authors.initials: BG
authors.lastname: Ropp
authors.forename: C
authors.initials: C
authors.lastname: Solomides
authors.forename: J
authors.initials: J
authors.lastname: Palazzo
authors.forename: M
authors.initials: M
authors.lastname: Bibbo
mesh_terms: D018262:Adenocarcinoma, Clear Cell / Q000175:diagnosis / Q000556:secondary; D018263:Adenocarcinoma, Follicular / Q000737:chemistry / Q000175:diagnosis* / Q000532:radiotherapy / Q000601:surgery; D018249:Adenoma, Oxyphilic / Q000737:chemistry / Q000175:diagnosis* / Q000532:radiotherapy / Q000601:surgery; D000328:Adult; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D013954:Thyroglobulin / Q000032:analysis; D013964:Thyroid Neoplasms / Q000737:chemistry / Q000175:diagnosis* / Q000532:radiotherapy / Q000601:surgery
chemical_list: D013954:Thyroglobulin