Carcinoma of the thyroid showing thymoma-like features

Abstract

A new case of thyroid carcinoma with thymoma-like features, occurring in a 45-year-old lady, is reported. In order to establish the incidence of residual thymic tissue, 2575 consecutive surgically removed thyroid glands were also examined. Thymic tissue was found to be present in up to 1.4% of the cases. The clinicopathological and immunohistochemical features of the case together with its possible relationship with the persistence of aberrant nodules of thymic tissue in the neck are discussed.

Carcinoma showing thymic-like elements—a rare malignancy of the thyroid gland

“…Twenty-one patients were treated by total thyroidectomy and one by irradiation only 8 . Cervical lymph node dissection was performed in 14 patients and five received postoperative irradiation.…”

Intrathyroidal epithelial thymoma (ITET)/carcinoma showing thymus‐like differentiation (CASTLE) exhibits CD5 immunoreactivity: new evidence for thymic differentiation

“…The neoplasm exhibits slow growth, with a favourable prognosis and tendency for late, local recurrence 1,2 . Histologically, ITET/CASTLE is lobulated and expansive, with fibrous septa, indistinct cell borders, and large vesicular nuclei with prominent nucleoli, a low mitotic count, and an associated lymphoplasmacytic infiltrate, resembling squamous cell or lymphoepithelioma-like carcinoma (LELC) of thymus, rather than typical benign thymoma [1][2][3][4][5] . Foci of typical papillary or follicular thyroid carcinoma are not seen [1][2][3][4][5] .…”

“…Histologically, ITET/CASTLE is lobulated and expansive, with fibrous septa, indistinct cell borders, and large vesicular nuclei with prominent nucleoli, a low mitotic count, and an associated lymphoplasmacytic infiltrate, resembling squamous cell or lymphoepithelioma-like carcinoma (LELC) of thymus, rather than typical benign thymoma [1][2][3][4][5] . Foci of typical papillary or follicular thyroid carcinoma are not seen [1][2][3][4][5] . Although ITET/CASTLE may have foci of squamous differentiation, it should be distinguished from squamous cell carcinoma of thyroid, which is a high-grade malignant neoplasm that is usually fatal [1][2][3] .…”

Ectopic Intrathyroidal Thymoma: A Case Report and Review

“…Thymomas account for approximately 20% of tumors in the anterior mediastinum, and less commonly present as primary tumors in the submandibular region, cervical region, pleural surface, pulmonary hilar regions, or inferior mediastinum close to the diaphragm. In such ectopic cases, thymomas likely either arise within vestigial remnants along the thymopharyngeal duct or follow early or late arrest of the descent of embryologic thymic tissue (2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14).…”