Hyperthyroidism and thyroid carcinoma

Abstract

Twenty-two of 251 patients with differentiated thyroid carcinoma suffered from or had a history of hyperthyroidism. They were hyperthyroid with a diffuse goitre (N=4), a diffuse goitre with a cold nodule (N= 10), a multinodular goitre (N=6), and an autonomous adenoma (N=2). Among the 22 patients, more than one fourth had an occult thyroid carcinoma with a diameter of 1 cm or less, those with the papillary tumour types, less frequently had lymph node metastases than the total group of patients with papillary carcinomas (13.3 vs 35.6%). The clinical courses of the 22 patients resembled those of the other thyroid carcinoma patients whose age and initial findings were comparable. In 643 patients who underwent surgery for hyperthyroidism the incidence of thyroid carcinoma was 2.3%. The increase in coincidence of hyperthyroidism and thyroid carcinoma repeatedly reported in recent years is probably ascribable primarily to extensive and improved diagnostics and not to a direct connection between hyperthyroidism and development of thyroid carcinoma. On the other hand, our findings do confirm that, even in the presence of hyperthyroidism, all thyroid nodules require careful diagnostics for exclusion of malignancy.Opinions differ as to whether a connection exists between hyperthyroidism and thyroid carcinoma. In 1937, Means (1) still considered hyperthyroid¬ ism to be an "insurance against cancer of the thy¬ roid". This assumption was questioned in the early fifties (2,3), and, by the mid-sixties, a connection was even seen between hyperthyroidism and thy¬ roid carcinoma (4). The carcinoma incidence was between 0.2 and 0.5% in the large investigation series of Beahrs et al. (2;3029 patients with Graves' disease), Sokal (3; 13621 patients with hyperthy¬ roidism) and the prospective study of Dobyns et al.

Contribution of scintigraphy and ultrasonography to the prediction of malignancy in thyroid nodules with indeterminate cytology

“…Uptake in the nodule indicates its benign nature and spares patients from surgery due to the argument of malignancy suspicion. In fact, hot nodules are rarely malignant (9)(10)(11)(12) and in the present study only 1/40 hot nodules (with indeterminate cytology) was a carcinoma.…”

Mortality from thyroid cancer in patients with hyperthyroidism: the Theagenion Cancer Hospital experience

“…Although there is insufficient evidence to base recommendations for any change in practice, clinicians managing patients with hyperthyroidism need to be aware of the possible increased risk of thyroid cancer in this patient group. In particular, the proposition that hot nodules are associated with exceedingly low probability of malignancy (6)(7)(8), needs to be re-evaluated in prospective studies.…”

“…The reported incidence of thyroid cancer found at surgery for hyperthyroidism ranges from 0.21 to 9.0% (1,3,4). The incidence of thyroid cancer may be increased in patients with Graves' disease presenting with a palpable nodule (5), while the probability of a hot nodule being malignant is low, ranging from 1 to 6% (6)(7)(8), but may be as high as 11% in children (9). Occasionally, some advanced thyroid cancers can cause hyperthyroidism due to autonomously functioning metastases (10,11).…”

Thyroid Disease in the Elderly

“…However, Tibaldi et al 83 found that, of 25 hyperthyroid patients, 21 had Graves’ disease, three had multinodular goiter, and one had a toxic nodule. Thyrotoxicosis may occasionally be caused by thyroid carcinoma 84 . In very rare cases, thyrotoxicosis may be the result of excess TSH secretion, either due to a pituitary adenoma or due to a selective pituitary resistance to thyroid hormone 85 .…”