Current treatment of Graves' disease

Safety and efficacy of surgical management of hyperthyroidism: 15-year experience from a tertiary care center in a developing country

BACKGROUND

Ideal management of toxic goiter still remains elusive. Though surgical management of toxic multinodular goiter (MNG) is well accepted, surgical treatment of Graves' disease (GD) is still controversial in view of the presumed increased incidence of complications. In this paper, we discuss the experience of the surgical management of hyperthyroidism at a specialized tertiary care endocrine center in a developing country, highlighting the minimal morbidity and satisfactory outcome in experienced hands.

MATERIALS AND METHODS

We retrospectively reviewed 325 consecutive patients with hyperthyroidism managed surgically from 1990 to 2005. The etiologic diagnoses were Graves' disease (185), toxic MNG (105), and autonomously functioning thyroid nodules (AFTN) (n = 35). The indications for surgery in Graves' patients were large goiter, relapse after antithyroid drug therapy (ATD), Graves' ophthalmopathy, and presence of nodule. The indications for surgery in toxic MNG were retrosternal extension (n = 15), compressive symptoms (n = 20), and large size (grade II). Among the AFTN nodule size, those greater than 4 cm (85%) formed the major indication for surgery. Subjects with GD and toxic MNG were subjected to subtotal thyroidectomy (n = 93 prior to 1995) or total thyroidectomy (n = 205 post-1995). Hemithyroidectomy was the procedure of choice in patients with AFTN.

RESULTS

Patients with Graves' disease were younger in age, with shorter mean duration of goiter when compared with the other 2 groups. Eight percent of patients with Graves' disease without a clinically palpable nodule and 25% of those with nodules had associated differentiated carcinoma, including papillary, follicular, and medullary thyroid cancer. Four percent of patients with toxic MNG had malignancy. Complications included temporary hypocalcemia (24%), permanent hypocalcemia (3%), and permanent vocal-cord palsy (1%).

CONCLUSIONS

Surgery for hyperthyroidism has negligible mortality and acceptable morbidity in experienced hands. It is a definite option in selected cases. Immediate and permanent cure of hyperthyroidism is achieved, with no recurrences, after total thyroidectomy. The cosmetic outcome is good, with excellent patient satisfaction and acceptance.

Factors affecting thyroid function after subtotal thyroidectomy for Graves' disease: case control study by remnant-weight matched-pair analysis

In order to determine whether there are any predictive factors, other than the amount of remnant thyroid tissue, for subsequent thyroid function after subtotal thyroidectomy for Graves' disease, thyroid function was assessed in 329 patients 3 years after surgery, and a case control study was carried out in euthyroid, hyperthyroid, and hypothyroid groups by remnant-weight matched-pair analysis. Factors that affected thyroid function 3 years after surgery were thyroid gland infiltration by lymphocytes and the thyrotropin binding inhibiting immunoglobulin (TBII) value in the hyperthyroid and euthyroid groups, and the free triiodothyronine (FT3) value at the time of surgery and lymph follicle formation in the thyroid gland in the hypothyroid and euthyroid groups. It is concluded that no single factor studied at surgery, other than the amount of remnant tissue, can predict thyroid function after subtotal thyroidectomy for Graves' disease.

The incidence of recurrence and hypothyroidism following treatment with antithyroid drugs, surgery or radioiodine in all patients with thyrotoxicosis in Malmö during the period 1970-1974

The incidence of recurrence and of hypothyroidism was determined in all new patients treated for thyrotoxicosis during the period 1970-1974 in an unselected, well-defined urban population. A total of 309 patients were followed up for a median time period of 108 (1-192) months. There was a cumulative incidence of 51% recurrence in patients who were treated with antithyroid drugs for Graves' thyrotoxicosis, whereas after surgery or radioiodine treatment there were few recurrences, but 32% and 78% cumulative incidences of hypothyroidism. There were no recurrences after surgery or radioiodine treatment in patients with toxic multinodular goitre or solitary toxic adenoma, but 29% and 40% cumulative incidences of hypothyroidism following radioiodine treatment. Late hypothyroidism occurred after surgery for Graves' thyrotoxicosis, and in all groups treated with radioiodine. Thus it is advisable that all patients with Graves' thyrotoxicosis, regardless of treatment, and all patients with toxic multinodular goitre or solitary toxic adenoma treated with radioiodine, should be followed up for many years, and probably for life.

Clinical and immunological studies on patients with Graves' disease preoperatively treated with corticosteroids and iodides

The purpose of this study was to evaluate the acute effects of corticosteroid and iodide preoperative therapy in patients with Graves' disease in terms of thyroid function and immunological parameters. The above combination was prescribed for 4 patients who had experienced severe side effects from antithyroid drugs (ATD) in order to reduce the possibility of post-thyroidectomy thyroid storm. Corticosteroids were employed daily for four days, and iodides were given daily for two weeks prior to thyroidectomy. The free T3 values decreased rapidly to euthyroid levels following the administration of both drugs, although the free T4 values were still much higher than normal in 3 of the 4 patients at the time of surgery. By comparison, 3 of 8 patients treated with ATD also had thyroid hormone levels above normal. Studies of lymphocyte subsets revealed that the percentage of helper T cells was significantly less in the corticosteroid-iodide treatment group than in the control and ATD groups. It is thus possible that postoperative thyroid storm might be prevented through corticosteroid-iodide therapy by virtue of the reduction of free T3 values to within the normal range by the time of surgery. The acute suppression of helper T cells was another results of this form of therapy observed.

Growth regulation of normal thyroids and thyroid tumors in man

Our studies using thyrocyte membranes from different human thyroid tissues, monolayer cultures of human thyrocytes, and the permanant cell line FTC-133 demonstrate the stimulatory effect of TSH on metabolism, DNA synthesis, and cell growth in human thyrocytes. Up- and down-regulation of cAMP cell content fails to show direct effects on DNA synthesis and cell growth in primary thyrocyte cultures in man. Increased AC responsiveness to TSH in adenomatous human thyroid tissues, when compared to normal thyroids of the same patient (p less than 0.005), is thus of only questionable importance for thyroid tumor growth. The permanant cell line FTC-133 was established from differentiated follicular human thyroid cancer cells. FTC-133 cells proved to be of particular usefulness in assessing growth regulation of human thyroid tissue. These cells could be propagated in serum free medium, showed thyroglobulin immunoreactivity and EGF receptors, lacked any fibroblast contamination, and responded to TSH and local active growth factors such as EGF and IGF with a stimulated [3H]thymidine incorporation. The latter could be shown in primary cell cultures of normal and pathological human thyrocytes as well. Additional to the stimulatory effect of TSH and IGF on [3H]thymidine incorporation, these substances show an additive effect when incubated simultaneously. Locally active growth factors and endocrine growth stimulation by TSH therefore act synergistically on thyrocyte growth in human thyrocyte cultures. Whether the TSH effect on cell growth is related to its stimulation of AC remains as yet questionable.

A comparative evaluation of the surgical and radioiodine treatments for Graves' disease

Radioactive iodine treatment is currently the most popular treatment modality for hyperthyroidism in many patients of the world. In Japan, however, a considerable number of patients with hyperthyroidism have undergone successful surgery. To elucidate the advantages and disadvantages of surgical and 131I treatment, the thyroid function of 66 patients from each group was compared, 5 to 8 years after treatment. None of the surgically treated patients had been reoperated upon on, whereas 12 (18 per cent) of the patients treated with 131I required 2 or more doses. The number of patients with normal ranges of serum T3, T4 and TSH values was almost identical: 33 (50 per cent) of the postoperative patients and 31 (47 per cent) of the post-irradiated patients. In the surgically treated group, there was no tendency for hypothyroidism to develop with the passage of the time. However, although the distribution of T3 and T4 in the normal control and postoperative groups showed a normal bell-shaped distribution, the post-irradiated group did not exhibit this distribution. The normal control group and the postoperative group showed positive correlations of T3 and T4 but the post-irradiated group did not (p less than 0.05). When the titers of antithyroglobulin and antimicrosomal antibodies prior to therapy were compared with those following therapy, they had decreased in 41 per cent and 76.8 per cent, respectively, of the postoperative cases, but in only 24.2 per cent and 45.5 per cent of the post-irradiated cases.