Thyroid Research and Practice

ORIGINAL ARTICLE
Year
: 2015  |  Volume : 12  |  Issue : 3  |  Page : 107--109

Hypothyroidism after hemithyroidectomy for colloid goiter: Is it a reality


Karan Gupta, Naresh K Panda, Prachi Jain, Jaimanti Bakshi, Roshan Verma 
 Department of Otolaryngology and Head-Neck Surgery, Postgraduate Institute of Medical Education and Research, Chandigarh, India

Correspondence Address:
Dr. Karan Gupta
Department of Otolaryngology and Head-Neck Surgery, Postgraduate Institute of Medical Education and Research, Chandigarh
India

Abstract

Objective: The objective was to determine the overall risk of hypothyroidism (clinical and subclinical) after hemithyroidectomy for colloid goiter. Materials and Methods: Prospective review of 54 patients who underwent hemithyroidectomy for colloid goiter at a tertiary care center from January, 2010 to December, 2012 with regular follow-up. Results: A total of 54 patients were included in the study with 38 females and 16 males (M:F = 1:3). Mean age was 38 years (range: 23-59 years). All underwent hemithyroidectomy for preoperative diagnosis of colloid goiter, which was confirmed on postoperative histopathological examination. Patients were kept on regular follow-up with repeat thyroid function tests after every 6 months. Mean follow-up was 30.7 months. Subclinical hypothyroidism was found in 8 patients (14.8% prevalence) at a mean follow-up of 16.7 months postsurgery. T3 and T4 levels were within normal limits in all patients with no clinical hypothyroidism detected. No patient was on thyroid hormone supplementation. Conclusion: Our study shows a 14.8% prevalence of subclinical hypothyroidism following hemithyroidectomy for colloid goiter. Patients with subclinical hypothyroidism are at an increased risk of developing clinical hypothyroidism. The risk of hypothyroidism after hemithyroidectomy is an important element in decision making for individual patient and health care provider.



How to cite this article:
Gupta K, Panda NK, Jain P, Bakshi J, Verma R. Hypothyroidism after hemithyroidectomy for colloid goiter: Is it a reality.Thyroid Res Pract 2015;12:107-109


How to cite this URL:
Gupta K, Panda NK, Jain P, Bakshi J, Verma R. Hypothyroidism after hemithyroidectomy for colloid goiter: Is it a reality. Thyroid Res Pract [serial online] 2015 [cited 2022 Aug 9 ];12:107-109
Available from: https://www.thetrp.net/text.asp?2015/12/3/107/159527


Full Text

 INTRODUCTION



Hemithyroidectomy is a frequently performed surgical operation. Indications for hemithyroidectomy include symptomatic unilateral goiter or toxic adenoma. Usually, its aim wass to exclude malignancy in patients with solitary thyroid nodules with suspicious or indeterminate characteristics at fine-needle aspiration cytology. [1] The majority of nodules are found to be histologically benign. [1],[2] The price that is paid for the additional certainty provided by surgery is not negligible; postoperative bleeding, laryngeal nerve injury, wound infection, and hypothyroidism are well-known side effects of hemithyroidectomy. [3]

Hypothyroidism can be accompanied by a range of clinical manifestations, negatively impacting health status. [3] Apart from the need for regular doctor visits and blood check-ups, long-term thyroid hormone therapy may be associated with accelerated loss of bone mineral density, atrial fibrillation, changes in left ventricular function, and impairment in psychological well-being. [4],[5],[6],[7],[8] The reported risk of hypothyroidism after hemithyroidectomy varies greatly in the literature.

The aim of the present study was to determine the overall risk of hypothyroidism after hemithyroidectomy for benign colloid goiter in preoperatively euthyroid patients, as well as the risk of clinically relevant hypothyroidism.

 Materials and Methods



After getting the ethical clearance from the Institutional Ethics Board, 54 patients (38 females and 16 males) with preoperative diagnosis of colloid goiter who underwent hemithyroidectomy at a tertiary care center from January, 2010 to December, 2012 were included in the study. The diagnosis of colloid goiter was confirmed on histopathology postoperatively.

Before taking up the patients for surgery, every patient underwent a preoperative ultrasound (USG) neck, fine needle aspiration cytology (FNAC) of the nodule in the thyroid and a baseline thyroid function test (TFTs) (T3, T4 and thyroid stimulating hormone [TSH]). Patients with no evidence of features of malignancy on USG neck with FNAC suggestive of benign colloid goiter who were euthyroid were only included in the study. Patients were kept on regular follow-up and along with a complete clinical examination; TFTs (T3, T4, and TSH) were done first after 1-month of the surgery and then every 6 months and recorded. The normal range of serum T3 (S. T3) was 0.9-2.7 nmol/L; S. T4 was 4-12.3 μg/dL; and S. TSH was 0.3-5.0 μIU/mL.

 RESULTS



A total of 54 patients (38 females and 16 males, F:M = 3:1) of benign colloid goiter who underwent hemithyroidectomy were included in the study. The diagnosis was confirmed on histopathology postoperatively. The mean age of patients was 38 years (range: 23-59 years). The patients were kept on regular follow-up with a mean follow-up of 30.7 months (range from 42 to 24 months). The TFTs were initially repeated 1-month after the surgery and then was done every 6 months. Of the 54 patients included in the study, 8 patients (14.8%) developed sub-clinical hypothyroidism with S. TSH value above 5.0 μIU/mL, usually seen at a mean follow-up of 16.7 months after surgery [Figure 1]. None of the patients developed clinical hypothyroidism till the end of the study, with normal S. T3 and S. T4 in all patients.{Figure 1}

None of the patients developed any overt signs of hypothyroidism on clinical examination.

Of the 8 patients who developed sub-clinical hypothyroidism after hemithyroidectomy for colloid goiter, 5 (62.5%) patients had a preoperative S. TSH value above 1 μIU/mL.

 DISCUSSION



The risk of hypothyroidism following hemithyroidectomy in the present study was 14.8%, with the risk of hypothyroidism in the literature ranges from 0% to 43%. [9],[10],[11],[12],[13] A meta-analysis from Verloop et al. puts the risk of hypothyroidism after hemithyroidectomy at 21%. [14] However, the problem with most of these studies is that they have included all thyroid pathologies ranging from benign goiters to malignant nodules in the study. The risk of hypothyroidism might vary between the various pathologies of the thyroid and thus can't be generalized for all cases of hemi-thyroidectomies. [15]

All the patients in our study developed sub-clinical hypothyroidism (elevated S. TSH >5 μIU/mL with normal S. T3 and S. T4) with no patients developing clinical hypothyroidism on long-term follow-up. Although subclinical hypothyroidism could have beneficial effects in the elderly, [16] most patients undergoing hemithyroidectomy are under the age of 65 years, and potential adverse consequences of subclinical hypothyroidism in middle-aged populations have been shown. [17],[18],[19],[20] Furthermore, patients with subclinical hypothyroidism are at increased risk of developing clinical hypothyroidism. [21] The clinical implications of sub-clinical hypothyroidism in patients who have undergone hemithyroidectomy is still not clear and further work is required to clarify this issue.

The majority of the patients develop hypothyroidism within first 6-12 months of the surgery, [15] but few might even develop hypothyroidism after 18-24 months after the surgery as seen in our study. Hence, a long-term follow-up is required in these patients to detect hypothyroidism after hemithyroidectomy and to manage the same.

In the literature concomitant thyroiditis in the excised thyroid lobe, preoperative TSH levels in the higher-normal range, and positive anti-thyroid peroxidase antibody levels are risk factors for the development of hypothyroidism after hemithyroidectomy. [15] The most significant predictor is the preoperative TSH level, with an approximate doubling of risk for each 1 unit of TSH increase over 1 μIU/ml. [22] In our study, 62.5% of the patients who developed hypothyroidism had preoperative S. TSH >1 μIU/mL.

 CONCLUSION



Our study shows a 14.8% prevalence of subclinical hypothyroidism following hemithyroidectomy for colloid goiter. Many potential adverse consequences of subclinical hypothyroidism can be seen in the middle-aged population. Furthermore, patients with subclinical hypothyroidism are at an increased risk of developing clinical hypothyroidism. The risk of hypothyroidism after hemithyroidectomy is an important element in decision making for individual patient and health care provider.

References

1American Thyroid Association (ATA) Guidelines Taskforce on Thyroid Nodules and Differentiated Thyroid Cancer, Cooper DS, Doherty GM, Haugen BR, Kloos RT, Lee SL, et al. Revised American Thyroid Association management guidelines for patients with thyroid nodules and differentiated thyroid cancer. Thyroid 2009;19:1167-214.
2Traugott AL, Dehdashti F, Trinkaus K, Cohen M, Fialkowski E, Quayle F, et al. Exclusion of malignancy in thyroid nodules with indeterminate fine-needle aspiration cytology after negative 18F-fluorodeoxyglucose positron emission tomography: Interim analysis. World J Surg 2010;34:1247-53.
3Stoll SJ, Pitt SC, Liu J, Schaefer S, Sippel RS, Chen H. Thyroid hormone replacement after thyroid lobectomy. Surgery 2009;146:554-8.
4Biondi B, Fazio S, Cuocolo A, Sabatini D, Nicolai E, Lombardi G, et al. Impaired cardiac reserve and exercise capacity in patients receiving long-term thyrotropin suppressive therapy with levothyroxine. J Clin Endocrinol Metab 1996;81:4224-8.
5Heemstra KA, Hamdy NA, Romijn JA, Smit JW. The effects of thyrotropin-suppressive therapy on bone metabolism in patients with well-differentiated thyroid carcinoma. Thyroid 2006;16:583-91.
6Sawin CT, Geller A, Wolf PA, Belanger AJ, Baker E, Bacharach P, et al. Low serum thyrotropin concentrations as a risk factor for atrial fibrillation in older persons. N Engl J Med 1994;331:1249-52.
7Schlote B, Nowotny B, Schaaf L, Kleinböhl D, Schmidt R, Teuber J, et al. Subclinical hyperthyroidism: Physical and mental state of patients. Eur Arch Psychiatry Clin Neurosci 1992;241:357-64.
8Saravanan P, Chau WF, Roberts N, Vedhara K, Greenwood R, Dayan CM. Psychological well-being in patients on 'adequate' doses of l-thyroxine: Results of a large, controlled community-based questionnaire study. Clin Endocrinol (Oxf) 2002;57:577-85.
9Berglund J, Aspelin P, Bondeson AG, Bondeson L, Christensen SB, Ekberg O, et al. Rapid increase in volume of the remnant after hemithyroidectomy does not correlate with serum concentration of thyroid stimulating hormone. Eur J Surg 1998;164:257-62.
10Lee JK, Wu CW, Tai FT, Lin HD, Ching KN. Changes in serum thyroid hormone and thyroglobulin levels after surgical treatments for toxic and non-toxic goiter. Thyroidology 1989;1:131-6.
11Lindblom P, Valdemarsson S, Lindergård B, Westerdahl J, Bergenfelz A. Decreased levels of ionized calcium one year after hemithyroidectomy: Importance of reduced thyroid hormones. Horm Res 2001;55:81-7.
12De Carlucci D Jr, Tavares MR, Obara MT, Martins LA, Hojaij FC, Cernea CR. Thyroid function after unilateral total lobectomy: Risk factors for postoperative hypothyroidism. Arch Otolaryngol Head Neck Surg 2008;134:1076-9.
13Koh YW, Lee SW, Choi EC, Lee JD, Mok JO, Kim HK, et al. Prediction of hypothyroidism after hemithyroidectomy: A biochemical and pathological analysis. Eur Arch Otorhinolaryngol 2008;265:453-7.
14Verloop H, Louwerens M, Schoones JW, Kievit J, Smit JW, Dekkers OM. Risk of hypothyroidism following hemithyroidectomy: Systematic review and meta-analysis of prognostic studies. J Clin Endocrinol Metab 2012;97:2243-55.
15Miller FR, Paulson D, Prihoda TJ, Otto RA. Risk factors for the development of hypothyroidism after hemithyroidectomy. Arch Otolaryngol Head Neck Surg 2006;132:36-8.
16Gussekloo J, van Exel E, de Craen AJ, Meinders AE, Frölich M, Westendorp RG. Thyroid status, disability and cognitive function, and survival in old age. JAMA 2004;292:2591-9.
17Biondi B, Cooper DS. The clinical significance of subclinical thyroid dysfunction. Endocr Rev 2008;29:76-131.
18Biondi B. Should we treat all subjects with subclinical thyroid disease the same way? Eur J Endocrinol 2008;159:343-5.
19Duntas LH, Biondi B. New insights into subclinical hypothyroidism and cardiovascular risk. Semin Thromb Hemost 2011;37:27-34.
20Razvi S, Shakoor A, Vanderpump M, Weaver JU, Pearce SH. The influence of age on the relationship between subclinical hypothyroidism and ischemic heart disease: A metaanalysis. J Clin Endocrinol Metab 2008;93:2998-3007.
21Dayan CM, Saravanan P, Bayly G. Whose normal thyroid function is better - Yours or mine? Lancet 2002;360:353.
22Said M, Chiu V, Haigh PI. Hypothyroidism after hemithyroidectomy. World J Surg 2013;37:2839-44.