Total Versus Subtotal Thyroidectomy

Trends and Outcomes of Surgical Management of Primary Papillary Carcinoma in the Pediatric Population

BACKGROUND

Childhood papillary thyroid cancer is more aggressive than carcinomas in adults. Current American Thyroid Association pediatric guidelines recommend a total or near-total thyroidectomy for all pediatric patients without gross evidence of lymph node metastases. Our objective is to analyze trends in the surgical management of pediatric papillary thyroid cancer and assess how well the guidelines are implemented.

METHODS

A retrospective cohort study of pediatric patients (ages 19 y and under) who underwent a thyroidectomy was conducted using the Surveillance, Epidemiology, and End Results database 2006-2017. Procedure type was classified as lobectomy or less and subtotal or total thyroidectomy. Descriptive statistics to illustrate patient and tumor characteristics as well as chi-square analysis to evaluate frequency of treatment with total thyroidectomies versus lobectomy or less were performed. Logistic regression analysis controlling for age, sex, size of tumor, rural versus urban institutions, and surgery year was conducted to identify factors predictive of procedure type.

RESULTS

A total of 2271 children underwent surgical management of papillary thyroid cancer between 2006 and 2017. Most patients received a subtotal or total thyroidectomy as surgical management (n = 2,085, 91.8%). One hundred eighty-six patients (8.2%) received a lobectomy or less. The number of lobectomies or less increased with time, with 41 (6.6%) patients between 2006 and 2009, 98 (8.0%) between 2009 and 2015, and 47 (11.1%) between 2016 and 2017 (P = 0.03). Mortality rates were low (n = 15, 0.7%). On logistic regression analysis, later stages, larger sizes, and earlier operative years were predictive of a near-total or total thyroidectomy.

CONCLUSIONS

Despite the American Thyroid Association Guidelines recommending a total thyroidectomy for pediatric well-differentiated thyroid cancer, the results of this study demonstrate that thyroid lobectomies are being performed in increasing frequency for smaller tumors in earlier stages of disease. Further investigation of whether this trend actually affects the outcomes in this patient cohort is needed.

Effectiveness of hemi-thyroidectomy in relieving compressive symptoms in cases with large multi nodular goiter

Introduction and importance

This case series describe the efficacy of hemi-thyroidectomy to relieve the compressive symptoms of cases having large multi-nodular goiter with preservation of the thyroid gland function. It's considered as an education tool for surgeons to perform safe hemi thyroidectomy to patients indicated for total removal of the gland. Compressive symptoms like mild/severe dysphagia or dyspnea associated with both benign and malignant thyroid disease. Although total thyroidectomy is currently considered the standard of care, hemi thyroidectomy is another surgical option with more benefits.

Case presentation

This case series was performed in a tertiary university hospital in Riyadh, Saudi Arabia. It included 35 females and 3 males above the age of 18 (mean age 42 years). All the operations were elective hemi-thyroidectomies performed by one surgeon, during 2019. Patients were complaining of; Voice Change, Neck Swelling, Dysphagia, Chocking, SOB, and Orthopnea. 20 of them were medically free and 18 patients had multiple associated comorbidities.

Clinical findings and investigations

Demographic data, baseline co-morbidities, TSH levels prior to surgery, thyroid gland size, FNA results and pre-operative symptoms were recorded. In addition, compressive symptomatology outcomes from two weeks to two years were recorded. Thirty-two of them (84%) had their symptoms resolve completely and did not need a completion surgery. Out of the 6 who had persistent symptoms, only two needed a completion surgery. Furthermore, only 34.2% required thyroid hormone replacement, 31.6% were euthyroid and 2.6% were hypothyroid preoperatively.

Interventions and outcome

Hemi thyroidectomy was chosen to avoid the risk of hormone replacement, and hypocalcemia. Our results revealed that compressive symptoms were effectively relieved in the majority of our patients. Only 2 patients had to undergo completion thyroidectomy due to compressive symptoms with no perioperative or postoperative complications.

Relevance and impact

We would recommend hemi thyroidectomy for cases of large multi nodular goiter due to its positive implication on patient outcome particularly if the patient refuse hormonal replacement.

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Compressive symptoms were effectively relieved in the majority of our patients.

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Only 2 patients had to undergo completion thyroidectomy due to compressive symptoms.

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No perioperative or postoperative complications were witnessed during the primary or completion surgery.

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The main drawback with hemithyroidectomy is recurrence.

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Nevertheless, most recurrences post thyroid surgery are asymptomatic and are diagnosed on ultrasonography.

Surgical management of primary thyroid tumours

The majority of patients who present with well differentiated thyroid cancer will require surgery, but decisions on the appropriate primary procedure will depend on information relating to patient, tumour and surgical factors. As the incidence of thyroid cancer continues to rise, it is critical that clinicians involved in the management of these cases understand the factors which underpin surgical decision making for individual patients. Reporting outcomes in well differentiated thyroid cancer (WDTC) has always been challenging due to the low recurrence and mortality rate of the disease. Although early data supported total thyroidectomy for all patients with >1 cm WDTC, more recent evidence has supported lobectomy in selected, low risk patients. As a result we have seen a change in the approach of international guidelines from a blanket statement that total thyroidectomy should be the treatment for all patients towards a more selective approach to therapy. When selecting the most appropriate surgical approach to WDTC, the primary aim is to minimize the chance of death from disease or further recurrence. Additionally the impact of potential side effects of treatment (laryngeal nerve injury and hypocalcaemia) must also be weighed in the balance. In this review of surgical management of WDTC we aim to present a historical perspective on this subject and explore the arguments for and against total thyroidectomy and thyroid lobectomy in the low-risk patient group.

DO ALL THYROID NODULES >4 CM NEED TO BE REMOVED? AN EVALUATION OF THYROID FINE-NEEDLE ASPIRATION BIOPSY IN LARGE THYROID NODULES

OBJECTIVE

Controversy exists regarding the ability of fine-needle aspiration (FNA) biopsy to rule out malignancy when thyroid nodules exceed 4 cm in diameter. The goal of this study was to provide data regarding FNA accuracy in a clinical setting for detecting/ruling out malignancy in large thyroid nodules (≥4 cm) and discuss FNA utility in guiding surgical decisions.

METHODS

All thyroid FNA cases performed at Marshfield Clinic from 1/1/2000 to 12/31/2010 followed by complete or partial thyroidectomy on nodules of at least 4 cm were identified. Demographics, medical history, nodule biopsy characteristics, surgical procedures, and diagnosis data were abstracted. FNA was compared to histologic evaluation of surgical specimens.

RESULTS

A total of 198 patients with large thyroid nodules were identified. Most had a single large nodule, but ~40% were multinodular, and 206 total nodules were assessed. Females outnumbered males, and the mean age was ~50 years. After surgery, cancer was histologically identified in 49/206 (23.8%) nodules, including 9/123 nodules that had been categorized as benign by FNA, corresponding to a false-negative rate of 7.3%. Sensitivity/specificity for detecting malignancy by FNA was ~80%. The positive predictive value (PPV) was just below 60%, and the negative predictive value (NPV) was 93% but rose to 96% when papillary microcarcinomas were excluded.

CONCLUSION

While FNA sensitivity in large nodules was relatively low, NPV was high, especially if incidental papillary microcarcinomas were excluded. When cancer prevalence and NPV are known, FNA can be a reliable "rule out" test in nodules ≥4 cm. This information is critical and can help guide the surgery decision, especially in high-risk patients. The decision for surgery should not be solely based on nodule size but should consider additional factors including cancer prevalence, clinical history, ultrasound features, surgical risk, and life expectancy.

ABBREVIATIONS

FNA = fine-needle aspiration NPV = negative predictive value PPV = positive predictive value.

Predictive factors for recurrence of differentiated thyroid cancer in patients under 21 years of age and a meta-analysis of the current literature

The influence of predictors for recurrence in relation to recurrence-free survival was analyzed retrospectively in differentiated thyroid cancer (DTC) patients under 21 years of age who underwent primary surgical treatment and who had a pathological diagnosis of DTC between 1983 and 2012 at Fudan University Cancer Hospital. Recurrences were retrospectively analyzed using a Cox regression model for the hazard ratio (HR) according to the clinicopathological features. A meta-analysis was performed with respect to the potential predictors for recurrence from current related studies. In the present study, there were 146 young patients aged from 7 to 20 years, with a female/male ratio of 2.65/1. Female gender was the only factor significantly associated with recurrence according to univariate (HR = 2.812, P = 0.037) and multivariate (HR = 4.107, P = 0.024) Cox regression analyses. Meta-analyses revealed that multifocality (HR = 1.91, P < 0.05) and presentation at diagnosis (HR = 1.39, P < 0.05) were highly associated with recurrence in young DTC patients. However, female gender and other factors, such as age (≤10 vs. 11-20 years), PTC (PTC vs. FTC), extrathyroidal extension, lymph node metastasis, total thyroidectomy (total vs. less than total), radioiodine therapy, and radiation history, were not associated with recurrence in young DTC patients. In conclusion, multifocality and presentation at diagnosis are strong predictive factors of recurrence in relation to recurrence-free survival. We recommend studies with larger sample sizes and longer follow-up to verify the influence of predictors for disease recurrence in young patients.

Total versus hemithyroidectomy for small unilateral papillary thyroid carcinoma

The correct approach to treat low-risk intrathyroidal papillary thyroid carcinoma (PTC) is controversial. Specific authors advocate unilateral thyroidectomy to minimize perioperative morbidity. The purpose of the present study was to determine an effective treatment strategy for patients with small unilateral papillary thyroid. This was a retrospective comparative analysis of 161 patients with PTC treated between 2001–2010; 60 consecutive patients following hemithyroidectomy and 101 patients following total thyroidectomy. Only patients with preoperatively-predicted localized unilateral disease were included. No between-group difference was identified in the rate of permanent surgical complications. In total, 36 hemithyroidectomy patients (60%) exhibited benign thyroid nodules in the contralateral lobe on preoperative ultrasound; this factor was found to positively correlate with the performance of ≥1 fine needle aspirations (FNAs) during follow-up. In addition, 47 hemithyroidectomy patients (78.3%) were prescribed thyroxine postoperatively. The hemithyroidectomy patients visited the endocrine clinic significantly less frequently than the total thyroidectomy patients (P=0.01), but were referred more often for neck ultrasound (P=0.03) and FNA (P<0.001). In addition, an increased number of patients in the hemithyroidectomy group were reoperated for suspected recurrent/persistent disease (P=0.06). Results of this retrospective study indicate that hemithyroidectomy for small unilateral PTC is associated with a significant follow-up burden and provides no clear patient benefit.

Lobectomy in follicular thyroid neoplasms' treatment

BACKGROUND

The purpose of this study is to evaluate the suitability of lobectomy with isthmectomy (LwI) in treatment of Follicular Thyroid Neoplasms (FTN), considering malignancy incidence and postoperative complications.

METHODS

192 patients (165 females; 27 males) who underwent LwI for FTN from 01/2005 to 12/2007 were retrospectively evaluated: clinical and pathological features, surgical complications and five year outcome. Inclusion criteria were cytological Bethesda category III and IV or histological follicular adenoma/carcinoma or follicular variant of papillary carcinoma). Metastatic disease or previous thyroidal surgery patients were excluded.

RESULTS

Mean age was 48.68 ± 14.93 yrs. Overall malignancy occurred in 88 patients (45.83%) and 80 (41.67%) underwent thyroidectomy completion (TC), mainly by index lesion's malignancy. Forty-one (21.35%) in LwI and 31 (38.75%) in TC specimens had associated malignancy, mainly papillary microcarcinomas. High preoperative Thyroid-Stimulating Hormone (TSH), histological multinodularity and, in cytology category IV, younger age, were significantly associated to malignancy. Permanent recurrent laryngeal nerve lesion occurred in 0.58% in Lwl and 1.52% in TC, and temporary dysphonia occurred in 9.25% and 6.06% (LwI and TC respectively). No LwI patients presented hypoparathyroidism whereas 3.03% in TC had temporary symptoms. In LwI, 36.70% developed hypothyroidism. Higher preoperative TSH was associated with hypothyroidism development.

CONCLUSIONS

LwI was inappropriate in 40.10% patients with malignancy who required TC and 23.12% had no functional benefit because post-LwI hypothyroidism. Nodular relapse was reported in at least 23/113 LwI patients (20.35%). We propose total thyroidectomy for patients with FTN preoperative TSH higher than 2.16 mU/L and, in Bethesda category IV, less than 39.5yrs.

Thyroid cancer: surgery for the primary tumor

Surgery is the mainstay of therapy for most patients who present with thyroid cancer. The surgeon must select an appropriate procedure based upon pre operative factors such as tumor histology, extent of primary disease, the presence of regional or distant metastases, associated disease in the contralateral thyroid lobe and the potential for post operative adjuvant therapy. Preservation of the vital structures in the central neck, including the recurrent and superior laryngeal nerves and the parathyroid glands is critical as is the maintenance of absolute hemostasis. In this review article we describe the management of Well Differentiated Thyroid Cancer (WDTC) presenting as a solitary nodule, WDTC in a background of multinodular disease and the management of WDTC presenting as advanced local disease. We go onto discuss the impact that regional and distant metastases have on the choice of surgical approach. The focus of this article is WDTC, however the principles of management of the primary in medullary and anaplastic carcinoma are also discussed.

Revised American Thyroid Association management guidelines for patients with thyroid nodules and differentiated thyroid cancer

BACKGROUND

Thyroid nodules are a common clinical problem, and differentiated thyroid cancer is becoming increasingly prevalent. Since the publication of the American Thyroid Association's guidelines for the management of these disorders was published in 2006, a large amount of new information has become available, prompting a revision of the guidelines.

METHODS

Relevant articles through December 2008 were reviewed by the task force and categorized by topic and level of evidence according to a modified schema used by the United States Preventative Services Task Force.

RESULTS

The revised guidelines for the management of thyroid nodules include recommendations regarding initial evaluation, clinical and ultrasound criteria for fine-needle aspiration biopsy, interpretation of fine-needle aspiration biopsy results, and management of benign thyroid nodules. Recommendations regarding the initial management of thyroid cancer include those relating to optimal surgical management, radioiodine remnant ablation, and suppression therapy using levothyroxine. Recommendations related to long-term management of differentiated thyroid cancer include those related to surveillance for recurrent disease using ultrasound and serum thyroglobulin as well as those related to management of recurrent and metastatic disease.

CONCLUSIONS

We created evidence-based recommendations in response to our appointment as an independent task force by the American Thyroid Association to assist in the clinical management of patients with thyroid nodules and differentiated thyroid cancer. They represent, in our opinion, contemporary optimal care for patients with these disorders.

SAFETY OF TOTAL THYROIDECTOMY

BACKGROUND

Total thyroidectomy is the preferred operation for multinodular goitre, Graves' disease and thyroid cancer. This study reviewed prospectively collected data on a personal consecutive series of 336 total thyroidectomies to assess whether results reported in world centres of excellence could also be achieved elsewhere.

METHODS

Between 1991 and 2004, 336 total thyroidectomies (85% over the last 6 years) of median age 53 years (13-86 years) and male : female ratio of 1:4.3 were undertaken for multinodular goitre 232 (69%), Graves' disease 26 (7.7%), thyroid cancer 60 (17.9%) and other benign conditions 17 (5.4%). Thirty-nine patients had 2-stage procedures. No patient required median sternotomy. Parathyroid autotransplantation was carried out in 43 (12.8%).

RESULTS

Permanent unilateral recurrent laryngeal nerve palsy occurred in 0.3% and permanent hypoparathyroidism in 1.8%. Significant temporary hypocalcaemia occurred in 13.4%. Non-significant temporary hypocalcaemia occurred in 23.8%, resulting in an overall rate of hypocalcaemia of 38.9% for the total series. Hypocalcaemia was more common after 1-stage compared with 2-stage surgeries (P < 0.001). Temporary hypocalcaemia was commoner after surgery for Graves' disease than surgery for other conditions. The rate of postoperative haemorrhage was 0.9% and wound infection, 1.5%. There was no postoperative mortality.

CONCLUSION

Total thyroidectomy removes the disease process completely, lowers local recurrence rates and avoids the substantial risks of reoperative surgery. Total thyroidectomy is safe and can be carried out with low complication rates that are equal to world centres of excellence.

Total thyroidectomy for clinically benign disease of the thyroid gland

Background

The role of total thyroidectomy in the treatment of patients with benign thyroid disease remains controversial. However, this procedure may be appropriate when both thyroid lobes are involved and when the risk of recurrence is significant. This study is a review of a 15-year experience of total thyroidectomy for benign disease.

Methods

Between 1988 and 2002, 834 patients underwent total thyroidectomy for clinically benign disease at the Sydney Head and Neck Cancer Institute, Royal Prince Alfred Hospital. There were 128 men and 706 women with a mean age of 52 (range 16–91) years. Indications for surgery were euthyroid multinodular goitre (MNG), toxic MNG and Graves' disease in 730 (87·5 per cent), 57 (6·8 per cent) and 47 (5·6 per cent) respectively. A total of 74 patients had previously undergone partial thyroidectomy.

Results

The incidence of temporary recurrent laryngeal nerve palsy was 2·3 per cent and that of temporary hypoparathyroidism 14·4 per cent. Permanent recurrent laryngeal nerve palsy occurred in 1·1 per cent, and 2·4 per cent of patients had permanent hypoparathyroidism. Neither the initial clinical diagnosis nor a history of previous treatment significantly influenced the rate of complications. The incidence of malignancy, other than incidental microscopic papillary carcinoma, was 4·6 per cent.

Conclusion

Total thyroidectomy has an important role in the management of patients with benign disease when both lobes of the thyroid gland are involved. This approach avoids disease recurrence and the increased risk of morbidity associated with secondary operation.

Current controversies in the management of pediatric patients with well-differentiated nonmedullary thyroid cancer: a review

Current treatment strategies for pediatric patients with nonmedullary, well-differentiated thyroid carcinoma (WDTC) are derived from single-institution clinical cohorts, reports of extensive personal experience, and extrapolation of several common therapeutic practices for this tumor in adults. Because pediatric WDTC is an uncommon malignancy, the issues of its optimal initial and subsequent long-term treatment and follow-up remain controversial. Pediatric patients with WDTC can be divided into two groups: children younger than 10 years of age and teenagers/adolescents between 10 and 18 years of age because these groups have different recurrence and mortality rates. We hereby present our views and interpret them in the light of the pertinent literature. Our recommendations on treatment strategies are more relevant for younger children. After midpuberty, optimal treatment is adequately addressed in the relevant literature on adults. For the majority of patients, total/near-total thyroidectomy is currently recommended as the standard initial therapy for WDTC. This is commonly followed by administration of radioiodine (RAI; (131)I) therapy to destroy residual normal thyroid tissue (remnant). Routine (131)I remnant ablation has been shown to: (1). decrease the risk of local recurrences, (2) increase the sensitivity of subsequent diagnostic RAI whole-body scanning (WBS), and (3) render serum thyroglobulin (Tg) a highly sensitive marker for recurrent/residual disease during long-term follow-up. We recognize that the above practices are not universally adhered to in children and adolescents, because the risk stratification and intensity of applied therapeutic measures are influenced by institutional traditions and personal experience. In our view, aggressive initial management, followed by evaluations at regular intervals after thyroidectomy and (131)I remnant ablation, in conjunction with long-term thyroid hormone suppressive therapy (THST), result in decreased recurrence rates in pediatric patients with WDTC. Follow-up examinations should include a diagnostic RAI ((131)I or (123)I) WBS and measurement of serum Tg, both performed under conditions of TSH stimulation, as well as neck ultrasonography (US). Our strategy is corroborated by data from retrospective clinical cohort studies. In this malignancy, no evidence of disease (NED) status can be defined as the combination of a negative diagnostic WBS and the presence of undetectable or low serum Tg levels, both tested under TSH stimulation. These findings should be accompanied by the absence of anatomically definable disease by standard imaging modalities, e.g., neck US or chest computed tomography (CT). Although the long-term survival rates are good overall in this disease, selected patients may require further surgery or (131)I therapy for the eradication or clinical control of metastases. Finally, and importantly, because the duration of follow-up is lifelong, the care of children with prior diagnosis of WDTC should be transferred to an adult endocrinologist after they reach adulthood, even if they have achieved NED status by that time.

Surgical considerations and approach to thyroid cancer

Patients with thyroid cancer can be safely treated by an experienced endocrine surgeon. More extensive initial surgery such as total or near-total thyroidectomy seems to decrease tumor recurrence and prolong life. When such operations can be done with minimal complications, we believe it is the treatment of choice because even low-risk patients have a 4% or 5% risk of eventually dying of thyroid cancer. If this risk of death from thyroid cancer can be decreased to 1% or 2% and the rate of serious complications is 1% or 2%, the authors believe total thyroidectomy is indicated. Most patients can be discharged within 1 day of total thyroidectomy.

Complications of thyroid surgery

BACKGROUND

The morbidity of thyroid surgery is low. Despite this, some authors advocate a subtotal thyroidectomy instead of a total thyroidectomy, to avoid the higher morbidity associated with a total thyroidectomy.

METHODS

We retrospectively evaluated the complications of thyroid surgery in Leiden between January 1, 1982 and October 1, 1990. Three hundred forty-one patients--261 women and 80 men--had 356 operations; 15 patients were operated on twice; there were 152 total hemithyroidectomies, 3 subtotal hemithyroidectomies, 33 total thyroidectomies, 122 bilateral subtotal hemithyroidectomies, 12 combinations of total and subtotal hemithyroidectomies, and 34 other operations.

RESULTS

Calculated for the nerves at risk (n = 489), the percentage of permanent recurrent nerve lesions was 3.1 (in the 5 most recent years it was 1.2%). There was no significant difference between total or subtotal (hemi)thyroidectomies. Initial symptomatic hypocalcemia necessitating supplementation was encountered 42 times (12.5%). The occurrence of permanent symptomatic hypocalcemia (6%) was not significantly different between total and subtotal (hemi)thyroidectomies (p = 0.06). The duration of surgery was 137.8 min for bilateral subtotal thyroidectomies and 182.9 min for bilateral total thyroidectomies (p < 0.0001). There was no difference in blood loss between total and subtotal (hemi)thyroidectomies.

CONCLUSIONS

Because total thyroidectomy carries a risk of complications similar to that for subtotal thyroidectomy, it is not logical to avoid total resections. If the number of total resections were increased, it is anticipated that fewer reoperations, which involve a relatively high morbidity rate, would have to be performed.

Identification of the external branch of the superior laryngeal nerve during thyroidectomy

Seventy-six patients underwent preoperative vocal evaluation and were randomized into 3 groups: (1) those with the superior thyroid pole dissected by the first author, with the external branch of the superior laryngeal nerve (EBSLN) identified by means of a nerve stimulator; (2) those patients whose dissection was executed by a resident, with no nerve search; and (3) those whose dissection was undertaken by the first author, without any nerve search. Postoperative analysis consisted of voice evaluation and electromyography of the cricothyroid muscle. No lesion occurred in patients in group 1. Twenty-eight percent of patients in group 2 and 12% in group 3 experienced a complete lesion of the EBSLN (p = 0.0123). When the patients in group 1 were compared with the patients with 62 nerves corresponding to nonoperated thyroid lobes, patients in group 1 exhibited no increased risk, whereas a significantly increased hazard was evident in both groups 2 (p = 0.0002776) and 3 (p = 0.0346393). In this study, effective prevention of iatrogenic EBSLN lesions during thyroidectomies was achieved only by the intraoperative identification of the nerve with the nerve stimulator.

The incidence of bilateral well-differentiated thyroid cancer found at completion thyroidectomy

The purpose of this study was to evaluate the surgical outcome of completion thyroidectomy in patients with presumed unilateral well-differentiated thyroid cancer (WDTC). The medical records of all patients having had unilateral thyroid lobectomy for WDTC, who subsequently underwent completion thyroidectomy, were reviewed. From 1980 to 1991, 60 patients with WDTC underwent completion thyroidectomy. Forty-seven patients had presumed unilateral WDTC, with no evidence of residual disease prior to their completion thyroidectomy. Twenty-five (53%) of these patients were found to have residual neoplastic disease in the neck. In 20 (43%) of 47 patients, a focus of cancer was found in the remaining thyroid lobe and in 5 additional patients no cancer was found in the contralateral lobe, however, unsuspected nodal disease was found. The remaining 13 of the 60 patients presented with either regional recurrence (n = 12) or distant metastases (n = 1) at the time of their completion thyroidectomy. All (92%) but 1 of these 13 patients had cancer in the remaining thyroid lobe. Multifocal disease in the primary lobe was associated with bilateral thyroid cancer (p less than 0.01). Complications were infrequent; transient hypocalcemia occurred in 5 (8%) patients, permanent hypoparathyroidism occurred in 1 (1.7%) patient, and transient recurrent laryngeal nerve palsy occurred in 3 (5%) patients. Residual WDTC was found in 37 (62%) of 60 patients undergoing completion thyroidectomy. Multifocal disease in the primary resected lobe was associated with a high incidence of contralateral thyroid cancer. Completion thyroidectomy is a safe procedure and may prevent the development of regional recurrence by eliminating an unsuspected focus of cancer.