Short- and long-term results of total vs subtotal thyroidectomies in the surgical treatment of Graves' disease

Terminal or truncal ligation of the inferior thyroid artery during thyroidectomy? A prospective randomized trial

INTRODUCTION

Thyroidectomy is a common procedure in general and endocrine surgery. The technique of ligation of inferior thyroid artery (ITA) has been invoked as a possible cause of appearance of postoperative hypocalcemia.

METHODS

We performed a prospective randomized study involving 184 patients undergoing total thyroidectomy to evaluate the differences of truncal ligation versus distal ligation of ITA in terms of postoperative hypocalcemia, vocal fold palsy, voice and swallowing impairment. The patients were divided into group A (trunk ligation of ITA) and group B (terminal branches ligation of ITA).

RESULTS

We evaluated postoperative PTH and calcemia (immediate, 6 and 12 months after thyroidectomy), postoperative day of discontinuation of calcium and vitamin D supplementation, voice and swallowing complaints, evaluated by mean of two specific tests available in literature, day of hospital discharge.

CONCLUSION

The only significant differences between the two groups were a higher immediate postoperative calcemia and a greater number of patients discharged without calcium and vitamin-D supplementation in the group B. In conclusion, no substantial differences were found between the two groups. The choice depends on the experience of the surgeon.

Thyroid surgery for Graves' disease and Graves' ophthalmopathy

BACKGROUND

Graves' disease is an autoimmune disease caused by the production of auto-antibodies against the thyroid-stimulating hormone receptor, which stimulates follicular cell production of thyroid hormone. It is the commonest cause of hyperthyroidism and may cause considerable morbidity with increased risk of cardiovascular and respiratory adverse events. Five per cent of people with Graves' disease develop moderate to severe Graves' ophthalmopathy. Thyroid surgery for Graves' disease commonly falls into one of three categories: 1) total thyroidectomy, which aims to achieve complete macroscopic removal of thyroid tissue; 2) bilateral subtotal thyroidectomy, in which bilateral thyroid remnants are left; and 3) unilateral total and contralateral subtotal thyroidectomy, or the Dunhill procedure. Recent American Thyroid Association guidelines on treatment of Graves' hyperthyroidism emphasised the role of surgery as one of the first-line treatments. Total thyroidectomy removes target tissue for the thyroid-stimulating hormone receptor antibody. It controls hyperthyroidism at the cost of lifelong thyroxine replacement. Subtotal thyroidectomy leaves a thyroid remnant and may be less likely to lead to complications, however a higher rate of recurrent hyperthyroidism is expected and revision surgery would be challenging. The choice of the thyroidectomy technique is currently largely a matter of surgeon preference, and a systematic review of the evidence base is required to determine which option offers the best outcomes for patients.

OBJECTIVES

To assess the optimal surgical technique for Graves' disease and Graves' ophthalmopathy.

SEARCH METHODS

We searched the Cochrane Library, MEDLINE and PubMed, EMBASE, ClinicalTrials.gov, and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP). The date of the last search was June 2015 for all databases. We did not apply any language restrictions.

SELECTION CRITERIA

Only randomised controlled trials (RCTs) involving participants with a diagnosis of Graves' disease based on clinical features and biochemical findings of hyperthyroidism were eligible for inclusion. Trials had to directly compare at least two surgical techniques of thyroidectomy. There was no age limit to study inclusion.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted and cross-checked the data for analysis, evaluation of risk of bias and establishment of 'Summary of findings' tables using the GRADE instrument. The senior review authors reviewed the data and reconciled disagreements.

MAIN RESULTS

We included five RCTs with a total of 886 participants; 172 were randomised to total thyroidectomy, 383 were randomised to bilateral subtotal thyroidectomy, 309 were randomised to the Dunhill procedure and 22 were randomised to either bilateral subtotal thyroidectomy or the Dunhill procedure. Follow-up ranged between six months and six years. One trial had three comparison arms. All five trials were conducted in university hospitals or tertiary referral centres for thyroid disease. All thyroidectomies were performed by experienced surgeons. The overall quality of the evidence ranged from low to moderate. In all trials, blinding procedures were insufficiently described. Outcome assessment for objective outcomes was blinded in one trial. Surgeons were not blinded in any of the trials. One trial blinded participants. Attrition bias was a substantial problem in one trial, with 35% losses to follow-up. In one trial the analysis was not carried out on an intention-to-treat basis.Total thyroidectomy was more effective than subtotal thyroidectomy techniques (both bilateral subtotal thyroidectomy and the Dunhill procedure) at preventing recurrent hyperthyroidism in 0/150 versus 11/200 participants (OR 0.14 (95% CI 0.04 to 0.46); P = 0.001; 2 trials; moderate quality evidence). Total thyroidectomy was also more effective than bilateral subtotal thyroidectomy at preventing recurrent hyperthyroidism in 0/150 versus 10/150 participants (odds ratio (OR) 0.13 (95% confidence interval (CI) 0.04 to 0.44); P = 0.001; 2 trials; moderate quality evidence). Compared to bilateral subtotal thyroidectomy, the Dunhill procedure was more likely to prevent recurrent hyperthyroidism in 20/283 versus 8/309 participants (OR 2.73 (95% CI 1.28 to 5.85); P = 0.01; 3 trials; low quality evidence). Total thyroidectomy compared with subtotal thyroidectomy conferred a greater risk of permanent hypocalcaemia/hypoparathyroidism in 8/172 versus 3/221 participants (OR 4.79 (95% CI 1.36 to 16.83); P = 0.01; 3 trials; low quality evidence). Effects of the various surgical techniques on permanent recurrent laryngeal nerve palsy and regression of Graves' ophthalmopathy were neutral. One death was reported in one study in year three of follow-up. No study investigated health-related quality of life or socioeconomic effects.

AUTHORS' CONCLUSIONS

Total thyroidectomy is more effective than subtotal thyroidectomy (both bilateral subtotal thyroidectomy and the Dunhill procedure) at preventing recurrent hyperthyroidism in Graves' disease. The type of surgery performed does not affect regression of Graves' ophthalmopathy. There was some evidence that total thyroidectomy compared with subtotal thyroidectomy conferred a greater risk of permanent hypocalcaemia/hypoparathyroidism, which however, was not seen in comparison with bilateral subtotal thyroidectomy. Permanent recurrent laryngeal nerve palsy did not seem to be affected by type of thyroidectomy. Health-related quality of life as a patient-important outcome measure should form a core determinant of any future trial on the effects of thyroid surgery for Graves' disease.

What is the best definitive treatment for Graves' disease? A systematic review of the existing literature

BACKGROUND

The management guidelines of the American Thyroid Association and American Association of Clinical Endocrinologists for Graves' disease (GD) include any of the following modalities: (131)I therapy, antithyroid medication, or thyroidectomy. No in-depth analysis has been performed comparing the treatment options, even though a single treatment option seems to be universally accepted.

METHODS

A systematic review of the literature was performed to examine contemporary literature between 2001 and 2011 evaluating the management options of GD. We compiled retrospective and prospective studies analyzing surgery and radioactive iodine. Outcomes of interest included postoperative hypothyroidism, euthyroidism, and persistent or recurrent hyperthyroidism without supplementation. Success was defined as postoperative euthyroidism or hypothyroidism. Failure was defined as persistent or recurrent hyperthyroidism.

RESULTS

Of the 14,245 patients, 4,546 underwent surgery [3,158 patients had subtotal thyroidectomy (STT) and 1,388 had total thyroidectomy (TT)] and 9,699 had radioactive iodine. The radioactive iodine group consisted of 2,383 patients receiving 1-10 mCi, 1,558 patients receiving 11-15 mCi, 516 patients receiving >15 mCi, and 5,242 patients receiving an unspecified amount. Surgery was found to be 3.44 times more likely to be successful than radioactive iodine (p < 0.001). STT and TT were found to be 2.33 and 94.45 times more likely to be successful than radioactive iodine (p < 0.001), respectively.

CONCLUSIONS

On the basis of the outcomes analyzed, surgery appears to be the most successful in the management of GD, with TT being the preferred surgical option.

Thyroid function after subtotal thyroidectomy in patients with Graves' hyperthyroidism

Background. Subtotal thyroidectomy is a surgical procedure, in which the surgeon leaves a small thyroid remnant in situ to preserve thyroid function, thereby preventing lifelong thyroid hormone supplementation therapy. Aim. To evaluate thyroid function after subtotal thyroidectomy for Graves' hyperthyroidism. Subjects and Methods. We retrospectively reviewed the medical records of all patients (n = 62) who underwent subtotal thyroidectomy for recurrent Graves' hyperthyroidism between 1992 and 2008 in our hospital. Thyroid function was defined according to plasma TSH and free T4 values. Results. Median followup after operation was 54.6 months (range 2.1–204.2 months). Only 6% of patients were euthyroid after surgery. The majority of patients (84%) became hypothyroid, whereas 10% of patients had persistent or recurrent hyperthyroidism. Permanent recurrent laryngeal nerve palsy and permanent hypocalcaemia were noted in 1.6% and 3.2% of patients, respectively. Conclusion. In our series, subtotal thyroidectomy for Graves' hyperthyroidism was associated with a high risk of postoperative hypothyroidism and a smaller, but significant, risk of persistent hyperthyroidism. Our data suggest that subtotal thyroidectomy seems to provide very little advantage over total thyroidectomy in terms of postoperative thyroid function.

Terminal ligature of inferior thyroid artery branches during total thyroidectomy for multinodular goiter is associated with higher postoperative calcium and PTH levels

PURPOSE

To evaluate the impact of truncal versus terminal branch ligature of the inferior thyroid artery (ITA) on postoperative calcium and PTH plasma levels in patients undergoing total thyroidectomy for multinodular goiter.

METHODS

A prospective randomized study was performed comparing a group of patients that underwent either truncal ligature of the ITA (group 1) or terminal ligature of ITA branches (group 2).

RESULTS

A series of 126 consecutive patients with non-toxic euthyroid multinodular goiter underwent total thyroidectomy. Truncal ligature of the ITA was performed in 63 patients (group 1) and terminal branch ITA ligature in 63 patients (group 2). Postoperative ionized serum calcium (mmol/L) at 24 hours was significantly lower in group 1 than in group 2 patients (1.22 ± 0.06 vs. 1.25 ± 0.05, P<0.05) and at 48 hours (1.20 ± 0.05 vs. 1.23 ± 0.05, P<0.05). Mean postoperative PTH levels (pg/mL) at 4 hours after thyroidectomy were significantly lower in group 1 than in group 2 patients (22.32 ± 11.64 vs. 25.82 ± 12.87, P=0.044). Mean hospital stay (hours) was higher in group 1 than in group 2 patients (87.47 ± 41.04 vs. 70.34 ± 24.82, P<0.05).

CONCLUSION

This study shows that terminal ligature of ITA branches during total thyroidectomy for multinodular goiter is associated with higher mean postoperative calcium and PTH levels, and shorter hospital stay. However, no significant difference in terms of permanent hypoparathyroidism was observed between the two groups.