A moot thyroid neoplasm: carcinoma or sarcoma

Poorly Differentiated Thyroid Carcinoma

Poorly differentiated thyroid carcinoma (PDTC) has been recognized for the past 30 years as an entity showing intermediate differentiation and clinical behavior between well-differentiated thyroid carcinomas (ie, papillary thyroid carcinoma and follicular thyroid carcinoma) and anaplastic thyroid carcinoma; however, there has been considerable controversy around the definition of PDTC. In this review, the evolution in the definition of PDTC, current diagnostic criteria, differential diagnoses, potentially helpful immunohistochemical studies, and molecular alterations are discussed with the aim of highlighting where the diagnosis of PDTC currently stands.

Ultrastructure of a primary fibrosarcoma of the human thyroid gland

A primary fibrosarcoma of the thyroid occurring in a patient with a nodular goiter is described. Light microscopy showed interwoven bundles of spindle cells admixed with plump ovoid cells, and foci of multinucleated giant cells. Remnants of distorted thyroid follicles were found only at the periphery of the tumor. "Transitional" epithelial elements were not discernible but the tumor resembled an anaplastic giant cell carcinoma. Multiple blocks studied by electron microscopy, however, revealed that the tumor cells, including the giant cells, have the ultrastructure features of a fibroblast.

Fibrosarcoma in the thyroid gland: recurrence treated with radiotherapy

A CASE of sarcoma of the thyroid gland in a 38-year-old woman is presented. The patient developed a large tumour in the neck within a year after an uncomplicated thyroidectomy. Biopsy from the tumour showed fibrosarcoma. The patient received irradiation to the neck given in two series and is alive 30 years after radiotherapy and without progression of the disease.