Poor differentiated "Insular" carcinoma of the thyroid

Abstract

Insular carcinoma of the thyroid (ICT) is an uncommon malignancy with intermediate morphology and behaviour between well-differentiated and anaplastic thyroid carcinoma. 70 year old woman with insular type of thyroid carcinoma is presented in this study. The patient with thyroid mass attended to Cerrahpasa Medical Faculty was operated as nodular guatr. 10 cm yellow-gray well defined tumor mass was observed in her thyroid specimen. In microscopic examination tumor cells with uniform small nucleus were in insular, trabecullar or solid pattern. They expressed thyroglobulin and NSE but not thyrocalcitonin positivity in immunohistochemical study. Tumor cells showed extended necrosis and vascular invasion. She applied with local recurrence in her neck and underwent radiation-therapy, one month later following her initial surgery. Postoperative 5th month she died. Pathologists have to know that insular carcinoma is a special type of thyroid cancer, and the prognosis is poorer than for the classic differentiated thyroid carcinoma.