Abstract
Two cases of anaplstic carcinoma of the thyroid gland with high blood levels of thyroglobulin are reported, together with an immunohistochemical study of thyroglobulin, vimentin and keratin. The patients were a 75-year-old woman and 69-year-old man. Both of them had largeanterior neck tumors, hoarseness and multiple lung metastases. Reduction surgery, local irradiation and chemotherapy with adriamycin were performed. In the former patient, lung metastases were reduced by the single administration of adriamycin. After the operation, the blood level of thyroglobulin fell down within normal range in each case. Immunohistochemically, anaplastic carcinoma cells showed no reaction to thyroglobulin but did positive reactions to keratin and vimentin in each tumor. However, coexisting differentiated thyroid cardinoma cells and normal thyroid tissues showed positive reactions to thyroglobulin. Therefore, it was suggested that the blood thyroglobulin was secreted by the differentiated thyroid carcinoma cells or fiew out from thyroid follicles destroyed by the tumor cells. Immunohistochemical staining of anaplastic carcinoma of the thyroid gland for the differentiation markers is thought to be important to explore the pathogenesis.
