Reemergence of thyroidectomy as treatment for Graves' disease

Total thyroidectomy as a method of choice in the treatment of Graves' disease - analysis of 1432 patients

Background

Graves’ disease represents an autoimmune disease of the thyroid gland where surgery has an important role in its treatment. The aim of our paper was to analyze the results of surgical treatment, the frequency of microcarcinoma and carcinoma, as well as to compare surgical complications in relation to the various types of operations performed for Graves’ disease.

Methods

We analysed 1432 patients (221 male and 1211 female) who underwent surgery for Graves’ disease at the Centre for Endocrine Surgery in Belgrade during 15 years (1996–2010). Average age was 34.8 years. Frequency of surgical complications within the groups was analyzed with nonparametric Fisher’s test.

Results

Total thyroidectomy (TT) was performed in 974 (68%) patients, and Dunhill operation (D) in 221 (15.4). Carcinoma of thyroid gland was found in 146 patients (10.2%), of which 129 (9%) were a microcarcinoma. Complication rates were higher in the TT group, where there were 31 (3.2%) patients with permanent hypoparathyroidism, 9 (0.9%) patients with unilateral recurrent nerve paralysis and 10 (1.0%) patients with postoperative bleeding. Combined complications, such as permanent hypoparathyroidism with bleeding were more common in the D group where there were 2 patients (0,9%), while unilateral recurrent nerve paralysis with bleeding was more common in the TT group where there were 3 cases (0,3%).

Conclusions

Frequency of complications were not significantly statistically different in relation to the type of surgical procedure. Total thyroidectomy represents a safe and efficient method for treating patients with Graves’ disease, and it is not followed by a greater frequency of complications in relation to less extensive procedures.

Cardiovascular morbidity and mortality in surgically treated hyperthyroidism - a nation-wide cohort study with a long-term follow-up

OBJECTIVE

Previous studies suggest that patients with hyperthyroidism remain at an increased risk of cardiovascular morbidity even after restoring euthyroidism. The mechanisms of the increased risk and its dependency on the different treatment modalities of hyperthyroidism remain unclear. The aim of this long-term follow-up study was to compare the rate of hospitalizations for cardiovascular causes and the mortality in hyperthyroid patients treated surgically with an age- and gender-matched reference population.

PATIENTS AND MEASUREMENTS

A population-based cohort study was conducted among 4334 hyperthyroid patients (median age 46 years) treated with thyroidectomy in 1986-2007 in Finland and among 12,991 reference subjects. Firstly, the hospitalizations due to cardiovascular diseases (CVD) were analysed until thyroidectomy. Secondly, the hazard ratios for any new hospitalization due to CVDs after the thyroidectomy were calculated in Cox regression analysis adjusted with the prevalent CVDs at the time of thyroidectomy.

RESULTS

The risk of hospitalization due to all CVDs started to increase already 5 years before the thyroidectomy, and by the time of the operation, it was 50% higher in the hyperthyroid patients compared to the controls (P < 0·001). After the thyroidectomy, the hospitalizations due to all CVDs (HR 1·15), hypertension (HR 1·23), heart failure (HR 1·17) and valvular diseases or cardiomyopathies (HR 1·55) remained more frequent among the patients than among the controls for 20 years after thyroidectomy. The increased morbidity was not clearly related to the aetiology of hyperthyroidism. Despite the increased CVD morbidity among the patients, there was no difference in cardiovascular mortality.

CONCLUSIONS

The present study shows that hyperthyroidism increases the risk of hospitalization due to CVDs and the risk is sustained up to two decades after effective surgical treatment. However, there was no excess CVD mortality in the middle-aged patient cohort studied.

The efficacy of thyroidectomy for Graves' disease: A meta-analysis

BACKGROUND

Surgery for Graves' disease was largely replaced in the mid-1900s by radioiodine and antithyroid drugs, due to the belief that they were more safe and effective. Since then, thyroid surgery has improved with preoperative drug therapy and modern operative techniques. Recent clinical studies of thyroidectomy for Graves' disease may not reflect outcomes accurately because of small sample size, especially when estimating ideal thyroid remnant size. The purpose of this study was to combine modern clinical trials and use meta-analysis to determine the overall efficacy of both total (TT) and subtotal thyroidectomy (ST) for Graves' disease, compare thyroid function and complications rates of TT and ST, and determine ideal thyroid remnant size.

METHODS

Meta-analysis was performed on published studies in which patients underwent either TT or ST for Graves' disease. Meta-analysis was performed by weighted least-squares linear regression. P < 0.05 was considered significant.

RESULTS

There were 35 studies comprising 7241 patients. Mean follow-up was 5.6 years. Overall, persistent or recurrent hyperthyroidism occurred in 7.2% of patients. TT was performed on 538 patients and hypothyroidism occurred in all cases. ST was performed in 6703 patients, 59.7% of whom achieved euthyroidism, 25. 6% became hypothyroid, and 7.9% had either persistent or recurrent hyperthyroidism. Permanent recurrent laryngeal nerve injury occurred in 0.9% of TT patients and 0.7% of ST patients (P = NS). Permanent hypoparathyroidism occurred in 1.6% of TT patients and 1.0% of ST patients (P = NS). There was an 8.9% decrease in hypothyroidism and 6.9% increase in euthyroidism for each gram of thyroid remnant (P < 0.0001 each).

CONCLUSIONS

Overall, thyroidectomy successfully treated hyperthyroidism in 92% of patients with Graves' disease. There were no cases of hyperthyroidism following TT. ST achieved a euthyroid state in almost 60% of patients with an 8% rate of persistent or recurrent hyperthyroidism. There was no significant difference in complication rates between TT and ST.

Antithyroid drugs for the treatment of hyperthyroidism caused by Graves' disease

Therapy for Graves' disease is not straightforward and often involves complex decision making. Long-term antithyroid drug therapy is appealing because it is nonablative, but it is not for everyone. The physician must weigh the advantages and disadvantages of antithyroid drug treatment and help the patient arrive at an individualized therapeutic strategy that is appropriate and cost-effective.

The aetiology, investigation and management of surgical disorders of the thyroid gland

There have been many recent advances in our understanding of thyroid disease, including thyroid physiology, the molecular biology of thyroid neoplasms, guidelines for the management of surgical thyroid disease and the operative approach to thyroidectomy. The control of thyroid growth and function is better understood now that the thyroid stimulating hormone (TSH) receptor has been characterized as a G-protein coupled transmembrane receptor. The peripheral action of thyroid hormones is also better understood in terms of their interaction with nuclear thyroid hormone receptors. An adenoma-carcinoma sequence for the development of thyroid neoplasms has been proposed based on the characterization of a number of proto-oncogenes and tumour suppressor genes, and different pathways for the development of papillary and follicular thyroid carcinoma have been demonstrated. Fine needle biopsy has become, over the past few years, the principal diagnostic technique for evaluation of thyroid nodules, and has resulted in a significant reduction in the need for surgery for benign thyroid nodules. The approach to the management of thyroid carcinoma can now be based on comprehensive scoring systems for assigning patients to a particular risk group, the most recent of which is the MACIS system based on distant metastases (M), age (A), completeness of resection (C), invasion (I) and size (S). The capsular technique of thyroidectomy as described has now been shown to be the best method to preserve parathyroid blood supply, protect the recurrent laryngeal nerve and minimize the complications of thyroid surgery.

Surgical treatment of Graves' disease

Seven men and 81 women were operated on for Graves' disease. Their median age was 33 years. Eleven patients underwent a bilateral subtotal lobectomy; 77 patients underwent a complete lobectomy with contralateral partial lobectomy. Forty-seven patients were treated before 1981. In these patients, the weight of the thyroid remnant was estimated empirically between 5 and 12 g. In the 41 patients treated since 1981, the remnant weight was estimated at 5 g by comparative weighing. There were no postoperative deaths. Functional results were established in 83 patients with an average follow-up of 50 months (range 12 to 156 months), with control of vocal cord mobility demonstrated by indirect laryngoscopy in 66 patients. Hormonal determinations were carried out in 74 patients. There were no cases of permanent hypoparathyroidism. Three patients (4.5 percent) had unilateral vocal cord dysfunction. Twelve patients (14.5 percent) had clinical and biologic hypothyroidism, which occurred within 1 year postoperatively in 11 cases. Seven patients (8.3 percent) had latent hypothyroidism only discovered by hormonal determinations. Fifteen patients (17.8 percent) had recurrent hyperthyroidism, 6 of whom were diagnosed by hormonal determinations. The actuarial recurrence rate increased progressively up to the sixth postoperative year. The only predictive factor for recurrence was the type of operation. Patients who underwent a bilateral subtotal lobectomy had more recurrences than patients who underwent a complete lobectomy with partial contralateral lobectomy (p less than 0.01). These results suggest that patients should be followed closely for many years and should undergo hormonal determinations regularly, as some recurrences can occur 5 years or more after operation with very few symptoms.

Psychiatric morbidity following total and partial thyroidectomy

Thirty subjects were screened for psychiatric morbidity approximately 7 years after they had undergone a thyroid operation. Thirteen were identified as "cases" by the General Health Questionnaire. Total and partial thyroidectomy subjects were compared. The total thyroidectomy patients identified as "cases" showed lower values of plasma calcium and higher values of inorganic phosphate than the partial thyroidectomy "cases", but the difference failed to reach statistical significance. No clinical or biochemical differences were found between cases and non-cases, irrespective of the type of operation.

Clinical management of patients with hyperthyroidism

The clinical management of the hyperthyroid patient is controversial, because there is no perfect treatment. Factors that influence the choice of therapy include the patient's age, sex, and type of hyperthyroidism, as well as patient and physician preference.

Hypocalcaemia after subtotal thyroidectomy for thyrotoxicosis

Eighty-one patients who underwent subtotal thyroidectomy for thyrotoxicosis had a 10 per cent incidence of symptomatic hypocalcaemia (corrected calcium less than 2.0 mmol/l) but only a 1.2 per cent incidence of prolonged hypocalcaemia. In the same patients only one had a transient right sided recurrent laryngeal nerve palsy. These results would seem to confirm the wisdom of lateral ligation of the inferior thyroid arteries to protect the recurrent laryngeal nerve. They lend no support to the suggestion that in order to protect parathyroid function this teaching be abandoned in favour of a policy of ligation of the arteries on the surface of the gland. Nevertheless, injury, devascularization or inadvertent removal of parathyroid tissue must still be the first practical consideration.

Beta-adrenoceptor blockade and anaesthesia for thyroidectomy

The administration of beta-adrenoceptor blocking drugs in the pre-operative preparation and operative management of thyrotoxic patients undergoing subtotal thyroidectomy is reviewed. Particular reference is made to some of the recent advances and it is emphasised that there has been a considerable reduction in the incidence of problems following judicious use of these drugs. The choice of anaesthetic technique employed for thyroidectomy is less important than the degree of control of thyrotoxicosis by the beta-adrenoceptor blocking drug. Propranolol has proved safe and effective for the majority of patients. The longer acting agent nadolol is easier to administer, particularly in the peri-operative period. Patients are rendered less thyrotoxic and safety thereby enhanced by adding potassium iodide for 10 days preoperatively. The combination of nadolol and potassium iodide offers real advantages in the preparation of the thyrotoxic patient for surgery.

Nadolol and potassium iodide in combination in the surgical treatment of thyrotoxicosis

With the two aims of rapidly reducing circulating thyroid hormone levels and controlling the symptoms of thyrotoxicosis, we have prepared 17 thyrotoxic patients for subtotal thyroidectomy, using a combination of potassium iodide administered for 10 days and the long acting beta-adrenoceptor antagonist nadolol. All 17 patients had normal serum thyroxine levels after 10 days of such treatment although 10 still showed elevation of serum tri-iodothyronine and considerable elevation in the most severely toxic patient. All patients were, however, clinically euthyroid preoperatively. Nadolol was administered once daily, hence avoiding the problems of drug administration in the immediate postoperative period, and plasma nadolol concentrations were high throughout the perioperative period. Serum thyroxine and tri-iodothyronine levels were significantly lower and reverse tri-iodothyronine levels higher 24 h postoperatively than before operation. All patients remained stable throughout the perioperative period. We conclude that this regimen has a number of advantages in the preparation of patients for thyroidectomy, in reducing the degree of thyrotoxicosis, in convenience of drug administration and in ensuring adequate circulating concentrations of beta-adrenoceptor antagonist whilst still retaining a relatively short preoperative phase of drug treatment.

Propranolol in the surgical treatment of hyperthyroidism, including severely thyrotoxic patients

The perioperative course of 44 hyperthyroid patients prepared for surgery with propranolol alone, including 11 with severe thyrotoxicosis was compared to that of 20 euthyroid patients prepared for surgery with carbimazole. Conventional propranolol at a dosage of 160 mg/day was frequently insufficient to produce a high degree of beta-adrenergic blockade, particularly in severely thyrotoxic patients. A greater than 25 per cent reduction in sitting pulse rate was associated with a high degree of beta-blockade. The clinical course of patients with mild or moderate thyrotoxicosis was similar to that of the patients prepared with carbimazole. In contrast, the course of severely thyrotoxic patients was complicated and, in addition to a higher preoperative propranolol dosage, these patients commonly required supplemental propranolol after operation. Although thyroid crisis did not occur in any patient, we cannot recommend the use of propranolol alone for the severely thyrotoxic patient.