HURTHLE CELL NEOPLASMS OF THE THYROID-GLAND - REASSESSMENT OF FUNCTIONAL-CAPACITY

We treated a hyperthyroid man and a euthyroid woman who had autonomously functioning Hurthle cell adenomas and demonstrated uptake of radioactive I-131 in a woman with recurrent Hurthle cell carcinoma. Since these tumors are thought to be inactive, we reassessed the functional capacity of Hurthle cell neoplasms by reviewing the medical records of all patients operated upon for these tumors at our medical center from 1950 through November, 1993. We also reviewed series of Hurthle cell neoplasms identified from a MEDLINE search of papers published from 1960 to November, 1993. We identified 92 patients with Hurthle cell neoplasms. Thyroid scintigraphy was performed in 28 of 72 patients with benign adenomas and six of 20 patients with Hurthle cell carcinomas. In addition to the two index cases, four euthyroid patients had hot nodules that partially suppressed the extranodular tissue; seven patients had warm nodules. Thyroid scans performed in patients with Hurthle cell carcinomas revealed five cold nodules and one warm nodule. Our index patient with carcinoma displayed elevated serum thyroglobulin levels when the cancer recurred. This patient and another had uptake of I-131 by recurrent or metastatic cancer that allowed for treatment with this nuclide. Of 539 patients identified in a literature survey, 489 had benign Hurthle cell adenomas and 50 had Hurthle cell carcinoma. Thyroid scans performed in 282 patients revealed 247 cold nodules, 20 warm nodules, and 8 hot nodules. Our results, added to those published in case series of Hurthle cell neoplasms, indicated that 4.4% of thyroid scans were hot and 8.9% were warm. We conclude that Hurthle cell neoplasms of the thyroid gland are functional more frequently than currently appreciated.