Risk of hypothyroidism following hemithyroidectomy: systematic review and meta-analysis of prognostic studies

Should Contralateral Nodules Be an Indication of Total or Completion Thyroidectomy for Patients With Unilateral Papillary Thyroid Carcinoma?

OBJECTIVE

To determine whether papillary thyroid carcinoma (PTC) patients with benign or nonsuspicious nodules in the contralateral lobe have a higher rate of recurrence or worse survival after lobectomy compared to those without nodules in the contralateral lobe.

METHODS

Adult patients who underwent lobectomy and were diagnosed with unilateral PTC (2013-2015), were identified from an institutional database. Patients who previously had cytologically benign nodules or nonsuspicious nodules in the contralateral lobe comprised the contralateral nodule (CN) group. Patients who did not have nodules in the contralateral lobe comprised the unilateral nodule (UN) group.

RESULTS

370 patients were included: 242 in the UN group and 128 in the CN group. After a median follow-up of 62 months (range, 16-85 months), recurrence was confirmed in 4.1% patients in the UN group and 5.5% patients in the CN group (p = 0.559). Clinical contralateral lobe PTC was detected in 2.9% (7/242) of patients from the UN group and 3.9% (5/128) of patients from the CN group (p = 0.601). The 5-year contralateral lobe recurrence-free survival (RFS) rates were 96.8% in the UN group and 97.4% in the CN group (p = 0.396). The 5-year loco-regional RFS rates were 98.4% in the UN group and 97.8% in the CN group (p = 0.690). The 5-year disease-specific survival rates were both 100%.

CONCLUSION

PTC patients with benign or nonsuspicious CNs have similar recurrence and survival rates after lobectomy compared to those without CNs. CNs alone should not be an indication for total or completion thyroidectomy.

Comparison of the Incidence of Postoperative Hypothyroidism in Patients Undergoing Conventional Thyroid Lobectomy and Pyramid- and Isthmus-Preserving Lobectomy

Hypothyroidism is a recognized sequela of conventional thyroid lobectomy. However, there have been no studies on the incidence of hypothyroidism following the preservation of the isthmus and pyramid during lobectomy. Therefore, in the present study, we compared the incidence of hypothyroidism following conventional lobectomy and lobectomy during which the isthmus and pyramidal lobe were preserved. Data for a total of 65 patients collected between September 2018 and April 2019 were reviewed retrospectively. Circulating thyroid-stimulating hormone (TSH) concentration was measured before and after surgery in a group who underwent conventional thyroid lobectomy (n = 29) and in a group in which the isthmus and pyramid were preserved (n = 36). We found no significant difference in TSH concentration between the two groups before surgery, or 3 months or 1 year after surgery. Thus, there might be no difference in the incidence of postoperative hypothyroidism between patients who undergo conventional thyroid lobectomy and those in which the isthmus and pyramid are preserved.

Does thyroid-sparing total laryngectomy decrease the risk of hypothyroidism?

BACKGROUND

Thyroid lobectomy is recommended with total laryngectomy for laryngeal cancer in the National Comprehensive Cancer Network ('NCCN') guidelines. However, it is associated with a 32-89 per cent risk of hypothyroidism, with or without adjuvant radiotherapy.

OBJECTIVE

The study aimed to determine whether preserving the whole thyroid, compared to a single lobe, does indeed significantly lower the incidence of hypothyroidism in the setting of total laryngectomy.

METHOD

A retrospective study was conducted at Groote Schuur Hospital in Cape Town, South Africa.

RESULTS

Eighty-four patients met the inclusion criteria. The overall incidence of hypothyroidism was 45.2 per cent. The incidence of hypothyroidism was significantly reduced in patients who underwent thyroid-sparing total laryngectomy compared to hemithyroidectomy (p = 0.037). Adjuvant radiotherapy was associated with a higher incidence of hypothyroidism (p = 0.001).

CONCLUSION

Thyroid-preserving laryngectomy should be advocated in carefully selected patients with advanced laryngeal carcinoma, as it reduces the incidence of hypothyroidism.

Selective use of Molecular Testing Based on Sonographic Features of Cytologically Indeterminate Thyroid Nodules: A Decision Analysis

BACKGROUND

Molecular diagnostics can allow some patients with indeterminate thyroid nodule cytopathology to avoid diagnostic hemithyroidectomy; however, the testing is costly. We hypothesized that molecular testing with the intention of preventing unnecessary diagnostic hemithyroidectomy would be cost-effective if this test was applied selectively based on sonographic risk of malignancy.

METHODS

A Markov model was constructed depicting a 40-year-old patient with a cytologically indeterminate thyroid nodule. Molecular testing of fine needle aspiration material was compared to a strategy of immediate diagnostic hemithyroidectomy. Data from a single tertiary-referral health system were reviewed to estimate the outcomes of molecular testing of indeterminate nodules stratified by the American Thyroid Association sonographic classification system. Other outcome probabilities and their utilities were derived from literature review. Costs were estimated with Medicare reimbursement data. A $100,000/QALY threshold for cost-effectiveness was applied. Sensitivity analysis was employed to examine uncertainty in the model's assumptions.

RESULTS

Of 123 patients who underwent molecular testing for indeterminate cytology, 12 (9.8%) were classified as high sonographic suspicion, 49 (40%) were intermediate suspicion, and 62 (50%) were low or very low suspicion. Molecular testing was only cost-effective when the pretest probability of a negative test was greater than 31%. The model was most sensitive to the cost of molecular testing and the quality adjustment factor for hypothyroidism.

CONCLUSIONS

In hypothetical modeling, molecular testing is only cost-effective for cytologically indeterminate thyroid nodules with sonographic features that are intermediate or low suspicion for malignancy. In nodules with high sonographic suspicion, molecular testing is rarely negative and appears to add minimal value.

Thyroid Lobectomy for Low to Intermediate Risk Differentiated Thyroid Cancer

Simple Summary

Total thyroidectomy used to be recommended for all thyroid cancers. We now know that some thyroid cancers have a relatively low risk of recurrence. Today, for some of these cancers, depending on the type of tumor, its’ size and other tumor characteristics, a thyroid lobectomy (or hemithyroidectomy) can be performed without increasing the patient’s risk of cancer recurrence. Thyroid lobectomy has the advantages of having less risk of surgical complications and a less frequent need for thyroid hormone replacement therapy. This approach is not optimal for all thyroid cancers, however, and careful tumor and patient selection are necessary. This review explains the rationale and criteria for patient selection for thyroid lobectomy for selected thyroid cancers.

Abstract

Many recent publications and guidelines have promoted a “more is less” approach in terms of treatment for low to intermediate risk differentiated thyroid cancer (DTC), which comprise the vast majority of thyroid cancers: less extensive surgery, less radioactive iodine, less or no thyroid hormone suppression, and less frequent or stringent follow-up. Following this approach, thyroid lobectomy has been proposed as a means of decreasing short- and long-term postoperative morbidity while maintaining an excellent prognosis for tumors meeting specific macroscopic and microscopic criteria. This article will examine the pros and cons of thyroid lobectomy for low to intermediate risk cancers and discuss, in detail, criteria for patient selection and oncological outcomes.

Hormonal Outcomes Following Hemithyroidectomy

OBJECTIVE

To assess hormonal outcomes and thyroid hormone (TH) replacement after hemithyroidectomy (HT).

STUDY DESIGN

Retrospective chart review.

SETTING

Quaternary care hospital system.

METHODS

A retrospective analysis was performed on patients who had an HT at Cleveland Clinic between 2000 and 2010 with outcomes assessed up to 5 years post-HT. Patients with overt hypothyroidism (OH; thyroid-stimulating hormone [TSH] >10 mIU/L, TSH >4.2 mIU/L on thyroid hormone [TH]), subclinical hypothyroidism (SH; TSH >4.2-10 mIU/L, no TH), or euthyroidism (EU; TSH 0.4-4.2 mIU/L, no TH) were compared. Patients with SH who returned to EU were compared to those who continued to have SH. For immediate start on TH, a receiver operating characteristic analysis was performed to determine dosage of TH above which suppression of TSH <0.4 mIU/L was predicted.

RESULTS

We identified 335 patients (average age 51 years, 78% female, median follow-up of 50 months). Of the 210 not immediately started on TH, 32.4% were OH, 13.3% were SH, and 54.3% were EU. EU patients were younger (48 years), had more remaining gland, were less likely to have lymphocytic infiltrate, and had a lower preoperative TSH (1.2 mIU/L). In the SH group, 58.3% of patients normalized their TSH. With immediate TH start, 45% developed suppressed TSH. Those on LT4 >1.05 mcg/kg/d were more likely to suppress (sensitivity 89%).

CONCLUSION

Most patients post-HT will remain EU, and immediate start of TH may lead to TSH suppression. Those with SH may ultimately normalize TSH. These findings together suggest that observation may be a better option than TH replacement after HT.

Predicting non-small-volume central lymph node metastases (>5 or ≥2 mm) preoperatively in cN0 papillary thyroid microcarcinoma without extrathyroidal extension

The ability to identify patients with aggressive papillary thyroid microcarcinoma (PTMC) from the low-risk patients is critical to planning proper management of PTMC. Lymph node metastases showed association with recurrence and low survival rate, especially in patients with >5 or ≥2 mm metastatic lymph nodes. Therefore, this study aimed to investigate the preoperatively predictive factors of non-small-volume (metastatic lymph nodes >5 or ≥2 mm in size) central lymph node metastases (NSVCLNM) in PTMC patients. A total of 420 patients with clinically node-negative (cN0) PTMC without extrathyroidal extension underwent thyroidectomy plus central neck dissection (CND) between January 2013 and December 2015, were retrospectively analyzed. Of the 420 patients, 33 (7.9%) had NSVCLNM. The 5-year recurrence-free survival was significantly less in cN0 PTMC patients with NSVCLNM, when compared with patients without NSVCLNM (80.8% vs 100%, P < .001). Multivariate logistic regression revealed age ≤36 years (P < .001), male sex (P = .002), ultrasonic tumor sizes of >0.65 cm (P < .001), and ultrasonic multifocality (P = .039) were independent predictive factors of NSVCLNM. A prediction equation (Y = 1.714 × age + 1.361 × sex + 1.639 × tumor size + 0.842 × multifocality -5.196) was developed, with a sensitivity (69.7%) and a specificity (84.0%), respectively, at an optimal cutoff point of -2.418. In conclusion, if the predictive value was >-2.418 according to the equation, immediate surgery including CND rather than active surveillance might be considered for cN0 PTMC patients.

High rate incidence of post-surgical adverse events in patients with low-risk papillary thyroid cancer who did not accept active surveillance

PURPOSE

To describe the outcomes and the incidence of adverse events following active surveillance (AS) versus immediate surgery in patients with low-risk papillary thyroid carcinoma (PTC).

METHODS

We prospectively evaluated 286 patients who attended the Hospital de Clínicas, with a single thyroid nodule <1.5 cm classified as Bethesda category V or VI (PTC). Those patients with no aggressive features were considered as harboring a low-risk PTC and were offered AS or immediate surgery. For patients who opted for AS, surgery was recommended if tumor progression was observed. Post-operative adverse events were recorded for those patients treated with surgery (after AS or immediate surgery).

RESULTS

From 286 eligible patients, 164 harbored a low-risk PTC. Among these, 75% (n = 123) underwent immediate surgery and 25% (n = 41) opted for AS. Within the last group, increase in tumor size more than 3 mm was observed in 14.6 and 4.8% was diagnosed with lymph-node metastases after a median of 37.5 months (range, 12-65) of follow-up. One hundred and thirty five patients underwent surgery: in 123, it was immediate after diagnosis and in 12 after a median of 35 months (range, 12-65) of AS. Both groups had excellent oncological outcomes. The frequency of postoperative adverse events was 24.4%, which was permanent in 9.6% of cases. The immediate-surgery group presented higher incidence of permanent vocal cord paralysis (2.4 vs. 0%); permanent hypoparathyroidism (5.7 vs. 0%) and local complications (4 vs. 2.4%) compared with the AS group, all non-statistically significant.

CONCLUSIONS

The high incidence of postoperative complications observed in our media could be avoided if AS was performed as the initial approach in patients with low-risk PTCs. The frequency of tumor growth and LN metastases during AS was similar to other series.

Postoperative thyroid hormone supplementation rates following thyroid lobectomy

BACKGROUND

Thyroid lobectomy is performed for symptomatic benign nodules, indeterminate nodules, or low-risk well differentiated thyroid cancer. We aimed to determine factors associated with thyroid stimulating hormone over goal (TH) following lobectomy.

METHODS

We performed a retrospective single-institution cohort study of patients undergoing thyroid lobectomy from January 2016 to December 2017. TH was defined as need for thyroid hormone in accordance with guidelines. Univariate and multivariate logistic regression analysis was performed.

RESULTS

One hundred patients were included and 47% developed. TH: 73% of those with cancer, 38% with benign pathology (p = 0.002). Patients with TH were more likely to have thyroiditis 26% versus 3.8% (p = 0.002); higher preoperative TSH: mean 1.88mIU/L (SD 1.17) versus 1.16mIU/L (SD 0.77) (p = 0.0002), and smaller remnant thyroid lobe adjusted for body surface area 2.99ml/m2 versus 3.72ml/m2 (p = 0.003).

CONCLUSIONS

After thyroid lobectomy, TH is associated with preoperative TSH level, thyroiditis, remnant thyroid volume, and malignancy. The majority of patients with final pathology of carcinoma will require thyroid hormone supplementation to achieve TSH goal.

Management and follow-up of differentiated thyroid cancer not submitted to radioiodine treatment: a systematic review

INTRODUCTION

The treatment of differentiated thyroid cancer (DTC) has been changing. In low (LR) and intermediate (IR) risk DTC, surgery is becoming more conservative and the usefulness of radioiodine (¹³¹I) has been questioned. An increasing number of patients are treated with lobectomy or total thyroidectomy (TTx), but without ¹³¹I. Consequently, the management and the follow-up of these patients need to be revised.

EVIDENCE ACQUISITION

We reviewed the available data about the management of these growing categories of patients. We focused on the emerging roles of the conventional tools in the follow-up [thyroglobulin (Tg), thyroglobulin antibodies (TgAb) and neck ultrasound (US)]. Moreover, we evaluated the changes in the use of levothyroxine (L-T4) therapy, and the role of the ongoing risk re-stratification.

EVIDENCE SYNTHESIS

Tg, TgAb and neck US continue to represent the cornerstone of the follow-up, however, a change in their interpretation is needed. In particular, the absolute value of Tg and TgAb lost their clinical meaning, while their trend over time acquired a greater value. At variance, the diagnostic role of neck US is becoming very relevant for the early identification of the local recurrences. In addition, L-T4 therapy should be personalized according with the type of surgery, the age of patients and their comorbidities.

CONCLUSIONS

Management of DTC treated with lobectomy or TTx but without ¹³¹I is worldwide changing. The evidences suggest that in this setting of patients with LR or IR of recurrences, a relaxed surveillance could represent the most reasonable choice.

Postoperative thyroid hormone supplementation rates following thyroid lobectomy

BACKGROUND

Thyroid lobectomy is performed for symptomatic benign nodules, indeterminate nodules, or low-risk well-differentiated thyroid cancer. We aimed to determine factors associated with need for thyroid hormone supplementation following thyroid lobectomy.

METHODS

We performed a retrospective single-institution cohort study of patients undergoing thyroid lobectomy from January 2016 to December 2017. Thyroid hormone supplementation was assessed postoperatively based on guidelines for thyroid stimulating hormone (TSH) level goal for benign (0.5-4.5mIU/L) or malignant (<2mIU/L) final pathology. Univariate and multivariate logistic regression analysis was performed.

RESULTS

One hundred patients were included and overall 47% required thyroid hormone supplementation after thyroid lobectomy: 73% of those with cancer, 38% with benign pathology (p = 0.002). Patients requiring thyroid hormone supplementation were more likely to have thyroiditis 26% versus 3.8% of those who remained euthyroid (p = 0.002); have a higher preoperative TSH: mean 1.88mIU/L (SD 1.17) versus 1.16mIU/L (SD 0.77) (p = 0.0002), and have a smaller remnant thyroid lobe adjusted for body surface area 2.99ml/m2 versus 3.72ml/m2 (p = 0.003).

CONCLUSIONS

After thyroid lobectomy, the need for thyroid hormone supplementation is associated with higher preoperative TSH level, thyroiditis, remnant thyroid volume, and malignancy on final pathology. The majority of patients with final pathology of carcinoma will require thyroid hormone supplementation to achieve TSH goal. For patients with benign pathology after thyroid lobectomy the majority will not require thyroid hormone supplementation to achieve TSH goal.

Active surveillance in low risk papillary thyroid carcinoma

In recent decades, while the incidence of thyroid cancer has increased exponentially around the world, mortality has remained stable. The vast majority of this increase is attributable to the identification of intrathyroidal papillary microcarcinomas, which exhibit slow growth rates with indolent courses. A diagnosis of thyroid cancer based upon the presence of these small tumors could be considered as an overdiagnosis, as the majority of these tumors would not likely result in death if left untreated. Although surgical resection was the classical standard therapy for papillary microcarcinomas, active surveillance (AS) has emerged over the last three decades as an alternative approach that is aimed to recognize a minority group of patients who will clinically progress and would likely benefit from rescue surgery. Despite the encouraging results of AS, its implementation in clinical practice is strongly influenced by psychosocial factors. The aim of this review is to describe the epidemiology, clinical evolution, prognostic factors, and mortality of papillary thyroid microcarcinomas. We also summarize the AS strategy according to published evidence, characterize the criteria for selecting patients for AS according to risk factors and environmental characteristics, as well as analyze the current limitations for AS implementation.

[The thyroid gland in old age : Physiology and pathology]

In healthy older people the metabolism of thyroid hormones is physiologically altered and can possibly even actively contribute to longevity. This should also be taken into consideration in the treatment of diseases of the thyroid and principally also for younger patients. For example, with progressing age comorbidities become more prevalent and especially in cardiovascular diseases, hyperthyroidism is less well tolerated, and should be treated more aggressively. Benign multinodular goiter also becomes more prevalent in old age and should be surgically treated when causing mechanical symptoms. The treatment concept for malignant diseases should be adapted to the holistic situation of the patient but principally in the same manner as in younger patients. Old and very old patients also benefit from adequate, risk-adapted treatment of thyroid gland diseases so that appropriate diagnostics and clarification are meaningful, regardless of age.

US-guided Microwave Ablation of Low-Risk Papillary Thyroid Microcarcinoma: Longer-Term Results of a Prospective Study

BACKGROUND

Papillary thyroid microcarcinoma (PTMC) has become a main cause of the extremely high incidence of thyroid carcinoma. This study aimed to evaluate the longer-term effectiveness of ultrasound (US)-guided microwave ablation (MWA) for treatment of low-risk PTMC with a large population.

METHODS

This prospective study was approved by ethics committee of our institution. MWA was performed under US-guidance for 119 unifocal PTMC patients without clinically cervical or distant metastasis. The target ablation zone exceeded the tumor edge judged by contrast-enhanced US to avoid marginal residue and recurrence. US and thyroid function evaluation were followed at 1, 3, 6, and 12 months after treatment and every 6 to 12 months thereafter. Any adverse event associated with MWA was evaluated.

RESULTS

The follow-up duration after MWA was 37.2 ± 20.9 months (range 12-101 months). Tumor volume decreased significantly from 1.87 ± 1.03 mL immediately after MWA to 0.01 ± 0.04 mL at the final evaluation (P < 0.001), with a mean volume reduction ratio of 99.4 ± 2.2% and 107 cases (93.9%) got complete remission. A patient was detected with cervical lymph node metastasis at 26-month follow-up and underwent 1 additional MWA treatment successfully. No distant metastasis was observed. All the acquired histological pathology results confirmed the absence of residual or recurrent tumor cells after MWA. No delayed complications associated with MWA were encountered for all patients.

CONCLUSIONS

Percutaneous MWA is technically feasible for complete PTMC destruction and showed well longer-term effectiveness; thus, it seems to be an effective nonsurgical therapy to complement the current recommendation for selected low-risk PTMC patients.

Thyroid isthmus agenesis and its clinical significance in a large-scale multidetector CT-based study

OBJECTIVE

The purpose of this study was to estimate the incidence and clinical significance of thyroid isthmus agenesis based on multi-detector CT imaging in a large-scale study.

METHODS

Data from 1601 patients who underwent neck multi-detector CT at our institution from January 2015 to March 2016 were included in this retrospective study. The morphology of each patient's thyroid gland was evaluated. We classified thyroid isthmus agenesis into two subgroups according to the thickness of the medial margin: clear-cut type (>4 mm) or tapering-edge type (≤4 mm). Associated thyroid pathologies were also evaluated.

RESULTS

Thyroid isthmus agenesis was present in 69 patients (41 males, 28 females), and its incidence was 4.77%. Eleven patients (0.76%) had the clear-cut type and 58 patients (4.01%) had the tapering-edge type. Papillary thyroid carcinoma was diagnosed in 4 patients (5.7% of isthmus agenesis patients). A total of 7 patients underwent thyroid function testing during the course of this study; 1 of these patients presented with borderline hyperthyroidism, and the remaining 6 were in a euthyroid state. The clear-cut type showed a statistically significant narrow gap and a high incidence of pyramidal lobes compared to the tapering-edge type.

CONCLUSION

Thyroid isthmus agenesis is not a rare developmental anomaly of the thyroid gland on multi-detector CT. Based on the metastatic pathophysiology of differentiated thyroid cancer, more extended indications for lobectomy are expected in differentiated thyroid cancer patients with thyroid isthmus agenesis.

Performance of a dual-component molecular assay in cytologically indeterminate thyroid nodules

PURPOSE

Deciding whether patients with a cytologically indeterminate thyroid nodule should be referred for surgery or for active surveillance is an important challenge for clinicians. The aim of this study was to evaluate the performance of a novel dual-component molecular assay as an ancillary molecular method for resolving indeterminate thyroid nodule cytology.

METHODS

We selected 156 thyroid nodules from those that had undergone fine-needle aspiration processed by liquid-based cytology and surgical resection between June 2016 and December 2017. The sample set included 63 nodules cytologically classified as indeterminate, and 93 other nodules randomly selected from those with non-diagnostic, benign, suspicious, or malignant cytology. Nucleic acids from each nodule were subjected to next-generation sequencing analysis for mutation detection in 23 genes and to digital polymerase chain reaction (PCR) evaluation for miR-146b-5p expression levels.

RESULTS

Used alone, mutation analysis in the indeterminate subset (cancer prevalence: 22.5%) displayed high sensitivity (89%) and NPV (96%). In contrast, the miR-146b-5p assay offered high specificity (93%) and PPV (93%). Combined use of both analyses improved panel performance by eliminating false-negative results.

CONCLUSIONS

These preliminary data suggest that a dual-component molecular test can increase the diagnostic accuracy of thyroid cytology alone by reducing the number of nodules that will be classified as indeterminate and increasing those that can be reliably classified as benign. If these findings are confirmed, this test can be considered for use in clinical practice and is expected to reduce diagnostic surgery and health care costs, and to improve patient quality of life.

Surgical Complications and Referral Patterns in 567 Patients with Differentiated Thyroid Cancer in the Northern Region of the Netherlands: A Population-Based Study Towards Clinical Management Implementation

BACKGROUND

In the Netherlands, differentiated thyroid cancer (DTC) is treated surgically in three different hospital types, including university, teaching, and non- teaching peripheral hospitals. This study evaluates postoperative complications and referral patterns in patients with DTC in the northern region of the Netherlands to gain an understanding on how to improve management implementation.

METHODS

Data from 567 patients diagnosed between 1989 and 2009 were obtained from the Netherlands Cancer Registry and were supplemented with information from hospital digital information systems and patient records from 15 hospitals: 1 university, 3 teaching, and 11 peripheral hospitals. Surgically treated patients with a histologically proven DTC derived from the original pathology reports were included.

RESULTS

Surgical treatment could be performed in a single procedure in 234 patients (41.3%), but several surgeries were needed in the remaining 333 patients (58.7%). Recurrent laryngeal nerve (RLN) palsy occurred after all types of thyroid surgical procedures, but mostly after initial (hemi)thyroidectomy and reoperations. RLN was temporary in 3.2% of the nerves at risk and persistent in 1.8%. Temporary hypocalcemia developed in 13.7% of patients, and persistent hypocalcemia occurred in 4.8%. Patients were mainly referred to the university hospital from a non-teaching (40.7%, 48/118) or teaching hospital (11.1%, 16/144); however, 80% of patients were not referred.

CONCLUSIONS

The complication rate and number of multiple surgeries support the efforts in optimizing clinical management in thyroid cancer. Careful considerations prior to initial surgical treatment by early discussion in telemedicine-based regional tumor boards could possibly prevent reoperations and potentially diminish complications.

Preventing blind thyroid lobectomy in patients with intrathyroidal hyperfunctioning parathyroid glands with radioguided enucleation

Aim: Hyperfunctioning intrathyroidal parathyroid glands are rare and often result in thyroid lobectomy. This study examines the utility of radioguided surgery to guide enucleation of intrathyroidal parathyroids. Methods: Between December 2002 and March 2018, 2291 patients underwent parathyroidectomy by one surgeon for primary hyperparathyroidism. A total of 74 (3%) patients had an ectopic intrathyroidal parathyroid gland and underwent radioguided. Results: All of intrathyroidal parathyroid glands were localized with the gamma probe. In vivo radionuclide counts were above 120% of the background in all but three patients. All intrathyroidal parathyroids were enucleated with the guidance of the gamma probe. Conclusion: Radioguided surgery is useful for intraoperative identification of hyperfunctioning, intrathyroidal parathyroid glands. This technique allows for enucleation of the abnormal parathyroid gland, avoiding thyroid lobectomy and preserving healthy thyroid parenchyma.

Parallels Between Low-Risk Prostate Cancer and Thyroid Cancer: A Review

Importance

Across many countries, a rapid escalation of the incidence of thyroid cancer has been observed, a surge that nonetheless underestimates the true extent of the disease. Most thyroid cancers now diagnosed comprise small, low-risk cancers that are incidentally found and are unlikely to cause harm. In many ways, prostate cancer similarly harbors a well-behaved subclinical reservoir, a long natural history, and superlative outcomes that have made active surveillance the de facto guideline recommendation for low-risk disease. This review highlights the parallels and differences between prostate cancer and thyroid cancer regarding screening, diagnosis, risk stratification, and considerations for active surveillance.

Observations

Prostate cancer and thyroid cancer have undergone recalibrated, de-escalatory shifts to counter changing epidemiologic landscapes. The US Preventive Services Task Force has issued cautionary recommendations on screening via prostate-specific antigen testing or neck ultrasonography, while the thresholds to performing biopsy have increased. Comparable changes to cancer terminology and staging have also helped alleviate patient anxiety and minimize pressure for overtreatment. Long-term, randomized prospective clinical trials for prostate cancer have established active surveillance as a first-line treatment approach for properly stratified low-risk patients, while observational trials for thyroid cancer have also made strides in defining risk and eligibility for surgery. Caveats requiring deeper investigation include aggressive disease in older patients, underestimation of the extent of the disease, and patient-physician bias in shared decision making. For prostate cancer, survival may not improve and function will likely worsen after intervention; for thyroid cancer, patients are younger, surgery is safer, and the bar for surveillance will likely be higher.

Conclusions and Relevance

Despite similarities in biological indolence between low-risk prostate and thyroid malignant neoplasms, key distinctions in life expectancy and treatment sequelae may ultimately confer somewhat disparate management paradigms for the 2 diseases. Nevertheless, the experience forged by prostate cancer trials serves as a model for thyroid cancer management, potentially reshaping the perception of active surveillance into a credible, valuable treatment modality.

Systematic Review of Recurrence Rate after Hemithyroidectomy for Low-Risk Well-Differentiated Thyroid Cancer

BACKGROUND

Surgical extent in the management of well-differentiated thyroid cancer (DTC) remains a recurrent subject of debate. This is especially relevant in low-risk DTC of 1-4 cm, which represent the majority of new thyroid cancer diagnoses. With trends towards treatment de-escalation and recent guidelines from the American Thyroid Association and British Thyroid Association endorsing hemithyroidectomy (HT) alone for low-risk DTC of 1-4 cm, we sought to systematically appraise the literature to examine recurrence rate outcomes after HT in this low-risk group.

SUMMARY

Searching PubMed, Cochrane Library, and Ovid MEDLINE, we conducted a systematic review to assess the survival and recurrence rate data presented in all published studies that had a cohort of patients treated with HT for the treatment of DTC. Pooled 10-year survival and recurrence rates, odds ratios, and 95% confidence intervals were calculated for meta-analysis. We identified 31 studies (with a total of 228,746 patients (HT: 36,129, total thyroidectomy, TT: 192,617), which had published recurrence and/or survival data for patients having had HT for DTC. We discovered a pooled recurrence rate of 9.0% for HT, which is significantly higher than in previously published reports. Further, this rate is maintained when examining patients within low-risk cohorts established with recognised risk classifications. We also discovered that of those patients who develop recurrent disease, 48% recur outside the central neck.

KEY MESSAGES

Our study provides a comprehensive systematic review of evidence aimed primarily at defining the recurrence rate in DTC after HT, and more specifically within the low-risk subgroup. We describe pooled recurrence and 10-year survival rates from a larger, broader, and more contemporary patient population than has been previously reported. Our findings indicate that there is a small but significantly higher recurrence rate after HT than TT, but the evidence base is heterogenous and subject to confounding factors and would ultimately benefit from prospective randomised trials to overcome these deficiencies.

Oncological impact of hypothyroidism and levothyroxine supplementation following hemithyroidectomy in patients with papillary thyroid carcinoma

BACKGROUND

We aimed to evaluate the oncological impact of hypothyroidism and levothyroxine (LT) supplementation after hemithyroidectomy in patients with papillary thyroid carcinoma (PTC).

METHODS

We retrospectively examined 401 patients who underwent hemithyroidectomy for classic PTC and who were postoperatively followed-up with ≥3 thyroid function measurements for ≥24 months.

RESULTS

During 77.4 months of follow-up, 268/401 patients (66.8%) developed hypothyroidism and 19/401 patients (4.7%) showed recurrence. Recurrence rates did not differ between the euthyroidism and hypothyroidism development groups. Recurrence rates were significantly lower in the LT group than in the no-LT group, although mean postoperative thyroid-stimulating hormone (TSH) levels were not different between the two groups. Univariate and multivariate analysis showed that tumors sized >1 cm and lack of LT supplementation were significantly associated with recurrence.

CONCLUSIONS

Postoperative hypothyroidism development was not a risk factor for PTC recurrence after hemithyroidectomy. Nevertheless, LT supplementation reduced recurrence risk without suppressing TSH.

Usefulness of 1-year of thyroid stimulating hormone suppression on additional levothyroxine in patients who underwent hemithyroidectomy with papillary thyroid microcarcinoma

Background

The purpose of this study was to identify usefulness of 1-year of thyroid stimulating hormone (TSH) suppression, on additional levothyroxine in patients who underwent hemithyroidectomy with papillary thyroid microcarcinoma (PTMC).

Methods

Two-hundred consecutive patients who had received hemithyroidectomy February 2011 to March 2013, were enrolled, retrospectively. Group 1, only, was taking levothyroxine for a year, postoperatively. We evaluated postoperative hypothyroidism through serum TSH level, measured periodically.

Results

Postoperative TSH >10 was significantly different, at 13% and 25%, between two groups (P=0.036). Twenty patients in group 1, and 32 patients in group 2, received additional levothyroxine. Multivariate analysis showed that 1-year suppression, clinical thyroiditis, and preoperative TSH >2, were significantly associated with additional levothyroxine (OR 2.17, P=0.025 and OR 2.00, P=0.046 and OR 2.64, P=0.006). Too, 1-year TSH suppression, preoperative TSH >2, were also significantly associated with postoperative TSH >10 (OR 2.55, P=0.022 and OR 2.22, P=0.048).

Conclusions

We suggest 1-year TSH suppression after hemithyroidectomy, for PTMC in patients with preoperative TSH >2 mU/L and clinical thyroiditis, to reduce additional levothyroxine.

Thyroid and Parathyroid Functions After Pharyngo-Laryngo-Esophagectomy for Cervical Esophageal Cancer

BACKGROUND

Cervical esophageal cancer (CEC) patients whose larynx function cannot be preserved often undergo chemoradiotherapy, whereas those with residual or recurrent lesions undergo a pharyngo-laryngo-esophagectomy (PLE); however, some need to undergo a pharyngolaryngectomy with total esophagectomy (PLTE) for synchronous or metachronous esophageal cancer. We retrospectively evaluated the relationship between preoperative irradiation (or the extent of esophageal resection) and postoperative endocrine complications in CEC, including hypothyroidism and hypoparathyroidism.

METHODS

The cancers of 35 (5.4%) of 678 esophageal cancer patients with esophagectomy treated in 2000-2017 were CECs. We also analyzed the 17 cases of CEC patients who underwent PLE with thyroid lobectomy-11 with irradiation before PLE and 6 without irradiation. Seven patients underwent a PLTE.

RESULTS

Hypothyroidism and hypoparathyroidism occurred in 14 and 12 patients, respectively. The hypothyroidism rate was significantly higher in patients with irradiation versus those without irradiation (100% vs. 50%; p = 0.010), and the hypoparathyroidism rate was significantly higher in the PLTE versus non-PLTE patients (100% vs. 50%; p = 0.026). The mean levothyroxine dosage was 1.60 μg/kg/day in the PLE patients post-irradiation.

CONCLUSIONS

Irradiation appears to be a risk factor for hypothyroidism after PLE with thyroid lobectomy, while PLTE might have some effect on hypoparathyroidism. Due to vocal function loss, PLE patients may experience symptoms from endocrine complications. Levothyroxine treatment soon after PLE for post-irradiation patients and patients requiring as-needed calcium or vitamin D supplementation based on biochemical hypocalcemia for PLE (especially PLTE), may be effective in preventing symptomatic endocrine complications.

Levothyroxine Supplementation Following Hemithyroidectomy: Incidence, Risk Factors, and Characteristics

BACKGROUND

The goal of the present study was to determine the actual incidence, predictive risk factors, and clinical characteristics of levothyroxine supplementation (LT4S) used for the management of hypothyroidism after hemithyroidectomy.

METHODS

From 2008 to 2015, we included 535 patients who underwent hemithyroidectomy. LT4S was initiated based on three major criteria: the development of overt hypothyroidism, subclinical hypothyroidism with thyroid-stimulating hormone (TSH) levels > 10 mIU/L, or subclinical hypothyroidism with TSH levels of 4.5-10 mIU/L with associated signs/symptoms.

RESULTS

During the 69-month follow-up period, 321 patients (60%) developed overall hypothyroidism following hemithyroidectomy, and 141 ultimately required LT4S, with an overall LT4S incidence of 26.4%. The most common cause of LT4S initiation was subclinical hypothyroidism with TSH levels > 10 mIU/L. In 141 patients with LT4S, the mean maintenance dose of levothyroxine was 1.34 μg/kg, and only 6 patients (4.3%) discontinued LT4S during the follow-up. The 1-, 3-, 5-, and 7-year LT4S-free survival rates of 535 patients were 88.6%, 80.2%, 73.8%, and 69.1%, respectively. Preoperative TSH levels > 2.12 mIU/L and coexistence of Hashimoto's thyroiditis were significantly associated with LT4S following hemithyroidectomy. The risk of LT4S increased by 1.401 times, as preoperative TSH levels increased by 1 mIU/L.

DISCUSSION

A quarter of patients required LT4S after hemithyroidectomy for the management of hypothyroidism, with a mean maintenance levothyroxine dose of 1.34 μg/kg. The preoperative TSH level and coexistence of Hashimoto's thyroiditis were significant predictive factors of LT4S following hemithyroidectomy.

Optimal Thyrotropin Suppression Therapy in Low-Risk Thyroid Cancer Patients after Lobectomy

Background: This study aimed to identify the clinical results after thyrotropin suppression therapy (TST) cessation and evaluated clinical factors associated with successful TST cessation. Methods: Patients who underwent lobectomy due to low-risk papillary thyroid carcinoma (PTC) were included in this study. We compared clinical characteristics and outcomes between patients who succeeded to stop TST and failed to stop TST. Results: A total of 363 patients were included in the study. One hundred and ninety-three patients (53.2%, 193/363) succeeded to stop TST. The independent associated factors for successful TST cessation were the preoperative thyroid-stimulating hormone (TSH) level and the maintenance period of TST. Patients with low TSH level showed a higher success rate for levothyroxine (LT4) cessation than patients with high TSH level (1.79 ± 1.08 and 2.76 ± 1.82 mU/L, p < 0.001). Patients who failed to discontinue TST showed a longer maintenance period of TST than patients who succeeded to discontinue TST (54.09 ± 17.44 and 37.58 ± 17.68 months, p < 0.001). Conclusions: Preoperative TSH level and maintenance period of TST are important factors for successful cessation of TST. If TST cessation is planned for patients who are taking LT4 after lobectomy, a higher success rate of TST cessation is expected with low preoperative TSH level and early cessation of LT4.

Graves' disease, multinodular goiter and subclinical hyperthyroidism

Subclinical hyperthyroidism is a common clinical entity, defined by serum TSH below the reference range, with normal FT4 and FT3 levels in an asymptomatic patient. Whether or not subclinical hyperthyroidism should be treated remains a matter of debate. Cross-sectional and longitudinal population-based studies demonstrate association of subclinical hyperthyroidism with risk of atrial fibrillation and osteoporosis, and with cardiovascular and all-cause mortality. However, there are no randomized clinical trials addressing whether long-term health outcomes are improved by treating subclinical hyperthyroidism; in the absence of evidence one way or the other, it seems appropriate to use decision trees taking account of TSH concentration and presence of risk factors (age>65 years or post-menopause, osteoporosis and cardiac disease).

Hemithyroidectomy for benign euthyroid asymmetric nodular goitre

BACKGROUND

There is no consensus on the optimal surgery extent for patients with benign euthyroid asymmetric nodular goitre (AMNG).

METHODS

We reviewed medical literature using the PubMed engine to address the following issues: definition and prevalence, rationale for hemithyroidectomy, long-term outcomes, follow-up, revision surgery and image-guided thermal ablation of contralateral benign thyroid nodules following hemithyroidectomy for AMNG.

RESULTS

In total, 102 articles were found in MEDLINE using a keyword search strategy; subsequently, we selected 36 articles with clinical pertinence.

CONCLUSIONS

AMNG is a common clinical and surgical problem. Depending on the extent of the disease and individual surgeon preferences, either unilateral or bilateral thyroidectomy can be performed. Hemithyroidecomy can be considered for some patients with AMNG and the low risk of recurrent disease as a safer alternative to total thyroidectomy but it requires life-long follow-up, is associated with a higher recurrence risk and a need for revision thyroidectomy in selected subjects.

FACTORS INFLUENCING THE SUCCESSFUL MAINTENANCE OF EUTHYROIDISM AFTER LOBECTOMY IN PATIENTS WITH PAPILLARY THYROID MICROCARCINOMA: A SINGLE-CENTER STUDY

Objective: This study aimed to evaluate factors influencing the successful maintenance of postoperative euthyroidism in patients who did not undergo immediate thyroid hormone replacement after lobectomy for papillary thyroid microcarcinoma (PTMC). Methods: From September 2015 to June 2017, 186 patients underwent lobectomy for PTMC in our hospital. Patients taking medications for hypothyroidism and hyperthyroidism before and after lobectomy were excluded. Multiple parameters, including sex, age, pre-operative free thyroxine (T4), thyroid-stimulating hormone (TSH), thyroglobulin (TG), and thyroid autoantibody levels, body mass index (BMI), postoperative histopathology of the thyroid gland, remnant thyroid gland volume, and session number of levothyroxine discontinuation were retrospectively evaluated. These factors were compared between groups based on the maintenance of postoperative euthyroidism. Results: In 88 of the 175 patients (50.3%), postoperative euthyroidism was successfully maintained without thyroid hormone replacement during the first year after lobectomy. There were significant differences in sex (P = .003), pre-operative TSH levels (P = .002), and histopathology of the thyroid gland (P = .035) between the groups showing maintenance success and failure. The group showing successful maintenance had a higher percentage of male patients, lower levels of pre-operative TSH, and normal parenchymal histology of the thyroid gland. However, there were no significant between-group differences in age, pre-operative free T4, TG, and thyroid autoantibody levels, BMI, remnant thyroid gland volume, and session number of levothyroxine discontinuation. Conclusion: Patient sex, pre-operative TSH levels, and histopathology of the thyroid gland may influence the maintenance of postoperative euthyroidism after lobectomy. Abbreviations: BMI = body mass index; PTMC = papillary thyroid microcarcinoma; RR = reference range; T4 = thyroxine; TFT = thyroid function test; TG = thyroglobulin; TSH = thyroid-stimulating hormone.

Thyrotoxicosis: Diagnosis and Management

Thyrotoxicosis is the clinical manifestation of excess thyroid hormone action at the tissue level due to inappropriately high circulating thyroid hormone concentrations. Hyperthyroidism, a subset of thyrotoxicosis, refers specifically to excess thyroid hormone synthesis and secretion by the thyroid gland. We performed a review of the literature on these topics utilizing published data in PubMed and MEDLINE. In this review, we discuss the more common etiologies of thyrotoxicosis, focusing on the current approach to diagnosis and management, new trends in those directions, and potential upcoming changes in the field.

Post-hemithyroidectomy hypothyroidism in non autoimmune thyroiditis patients: Incidence, risk factors and duration of follow up

BACKGROUND

Hemithyroidectomy has a known but less predictable sequelae of hypothyroidism. Presence of anti-thyroid antibody is known, well studied risk factor. Other postulated risk factors include higher pre-operative TSH level and lower ratio of post-operative thyroid remnant to the patient's weight. We reviewed our data to address the above mentioned risk factors.

METHOD

This was a retrospective study done in National Cheng Kung University Hospital, Taiwan from 2015 to 2017. 125 patients underwent hemithyroidectomy, but 24 patients were excluded due to autoimmune thyroiditis, which was determined as the exclusion criteria. Standard panel of blood investigations were taken in each clinic visit before and after operation. A neck ultrasound was done 2 months post-operatively to assess the thyroid remnant. Chi-square test was used for categorical data analysis. Independent student t-test was used for continuous data with parametric distribution and Mann-Whitney U test for non parametric data. p < 0.05 was taken as statistically significant.

RESULT

The mean duration of follow up was 29.3 months. 4 out of 101 patients had clinical hypothyroidism; 23 patients developed subclinical hypothyroidism post-hemithyroidectomy. 6 patients of subclinical hypothyroidism had spontaneously recovered within 1 year. Pre-operative TSH >2.0 uIU/mL was a risk factor as Chi square test showed p < 0.001. However, thyroid remnants were found not to be a risk factor with the Mann-Whitney U test of p = 0.928.

CONCLUSION

Minimum 1 year of follow up for hemithyroidectomy patients was suggested in order not to miss patients developing hypothyroidism post-operatively.

Treatment of thyroid nodules with radiofrequency: a 1-year follow-up experience

PURPOSE

The aim of this study is to assess the effectiveness and safety of radiofrequency ablation (RFA) in debulking benign solid thyroid nodules.

MATERIALS AND METHODS

This is a retrospective review of 77 patients with predominantly solid thyroid nodules treated with RFA in a single center between 2013 and 2016. All patients declined or were not eligible for surgery. Benign proven thyroid nodules causing compressive symptoms and cosmetic concerns were considered for treatment. Nodule volume, thyroid nodule related compressive symptoms, cosmetic concerns and thyroid function were evaluated.

RESULTS

All patients underwent a single treatment session. Mean nodule volume decreased from 17.9 ± 15.6 mL at baseline to 5.2 ± 7.4 after 12 months with a volume reduction ratio (VRR) of 70.9% ± 20.8%. There were no identifiable factors predictive of response to RFA. Median cosmetic and symptom scores of the entire population decreased from 3 [2-4] and 3 [0-10] to 1 [1-3] (p < 0.001) and 0 [0-5] (p < 0.001), respectively. No major complications occurred and RFA did not affect thyroid function when normal.

CONCLUSION

RFA induces substantial volume reduction of predominantly solid thyroid nodules and improves compressive symptoms and cosmetic concerns. RFA does not impact normal thyroid function and has an acceptable safety profile.

Management of Subclinical and Overt Hypothyroidism Following Hemithyroidectomy in Children and Adolescents: A Pilot Study

Background: To reduce surgical complications and avoid lifelong thyroid hormone replacement, hemithyroidectomy is preferred in children and adolescents with benign nodular thyroid disease. However, hypothyroidism following hemithyroidectomy may occur, and postoperative thyroid hormone replacement for hypothyroidism following hemithyroidectomy is usually administered without a full understanding of the clinical characteristics of hypothyroidism. Methods: To investigate the incidence and risk factors of hypothyroidism after hemithyroidectomy in children and adolescents, and to identify whether postoperative thyroid hormone replacement is necessary, a retrospective review of 43 patients under 18 years of age who underwent hemithyroidectomy from January 2009 to October 2016 was conducted. All hypothyroid patients were retrospectively analyzed to determine the incidence and predisposing factor(s) of postoperative hypothyroidism. All patients were measured regarding age, sex, serum thyrotropin (TSH), anti-thyroid antibody, and histological evidence of lymphocytic infiltration. Hypothyroid patients were measured for symptoms, timing of diagnosis, and thyroid hormone replacement. Results: The mean age at the time of surgery was 13.65 ± 3.04 years. Of the cohort, 34 patients were female (79.07%), and the mean follow-up time was 28 ± 9 months. Hypothyroidism was diagnosed in 11 of the 43 patients. The mean postoperative TSH level was 7.17 ± 2.13 μIU/ml. The mean preoperative TSH level was 3.11 ± 0.59 μIU/ml in hypothyroid patients compared with 1.92 ± 0.72 μIU/ml in euthyroid patients (P < 0.05). A preoperative TSH level >2.2 μIU/l and lymphocytic infiltration graded 3 or 4 were found to be independent risk factors for the development of hypothyroidism. There were no significant differences between groups in terms of patient age or sex. Conclusions: In the pediatric and adolescent population, patients with elevated preoperative TSH levels or the presence of lymphocytic infiltration may increase the risk of risk of hypothyroidism. In our study, postoperative levothyroxine (L-T4) treatment was necessary in 16.28% of cases after hemithyroidectomy. Patients with mild postoperative hypothyroidism should be followed up, without the need for immediate L-T4 replacement, so as to expect patients to recover spontaneously.

European Perspective on 2015 American Thyroid Association Management Guidelines for Adult Patients with Thyroid Nodules and Differentiated Thyroid Cancer: Proceedings of an Interactive International Symposium

BACKGROUND

The American Thyroid Association (ATA) management guidelines for patients with thyroid nodules and differentiated thyroid cancer (DTC) are highly influential practice recommendations. The latest revision appeared in 2015 ("ATA 2015"). These guidelines were developed predominantly by North American experts. European experts frequently have different perspectives, given epidemiological, technological/methodological, practice organization, and medicolegal differences between the respective regions.

SUMMARY

Divergent viewpoints were the focus of an invited symposium organized by the European Association of Nuclear Medicine involving 17 European thyroidologists, four ATA Guidelines Taskforce members, and an audience of 200 international experts. The group discussed the preoperative assessment of thyroid nodules, surgery and the role of pathology, radioiodine (RAI) therapy (RAIT), the assessment of initial therapy and dynamic risk stratification, and the treatment of persistent disease, recurrences, and advanced thyroid cancer. The dialogue resulted in this position paper contrasting European and ATA 2015 perspectives on key issues. One difference pertains to the permissiveness of ATA 2015 regarding lobectomy for primary tumors ≤4 cm. European panelists cited preclusion of RAIT, potential need for completion thyroidectomy, frequent inability to avoid chronic thyroid hormone replacement, and limitations of supportive evidence as arguments against widely applying lobectomy. Significant divergence involved ATA 2015's guidance regarding RAIT. European panelists favored wider use of postoperative RAIT than does ATA 2015. Rationales included the modality's association with favorable patient outcomes and generally limited toxicity, and lack of high-quality evidence supporting withholding RAIT. Additionally, European panelists favored recombinant human thyrotropin (rhTSH) in more settings than does ATA 2015, citing avoidance of hypothyroid morbidity and quality-of-life impairment, without apparent sacrifice in oncologic outcomes. Based on clinical evidence plus theoretical advantages, European experts advocated dosimetric versus fixed-activity RAIT approaches for advanced DTC. European panelists noted that the ATA 2015 risk-stratification system requires information sometimes unavailable in everyday practice. ATA 2015 recommendations regarding RAI-refractory DTC should consider potential palliative benefits of RAIT in patients who also have RAI-susceptible lesions.

CONCLUSIONS

European panelists suggested modifications to approximately one-third of ATA 2015 recommendations. Varying European and ATA 2015 perspectives can stimulate analysis and discussion of the literature and performance of primary research to resolve discrepant recommendations and potentially improve patient outcomes.

Predictors of thyroxine replacement following hemithyroidectomy in a south east Asian cohort

BACKGROUND

Thyroxine replacement following a hemithyroidectomy is not commonly discussed during consent for the procedure as the risk of hypothyroidism is perceived to be low.

METHODS

Retrospective review of 901 patients who underwent hemithyroidectomy at a tertiary referral institution during the period January 2000 to December 2015. The main outcome studied was the overall incidence of hypothyroidism and the associated risk factors.

RESULTS

Hypothyroidism developed in 123 (13%) patients and 94 patients (10%) required hormone supplementation over a mean follow up of 21 months (range 1-168 months). Preoperative TSH of more than 2.5 was seen in 38 of 123 (31%) of patients. Presence of diffuse thyroiditis was the only independent risk factor on multivariate analysis (P = 0.002) found to be associated with the development of hypothyroidism.

CONCLUSION

After thyroid lobectomy, approximately one in 10 patients requiring thyroid hormone treatment for hypothyroidism. Presence of diffuse thyroiditis is a significant risk factor for hypothyroidism.

Thyroid nodule recurrence following lobo-isthmectomy: incidence, patient's characteristics, and risk factors

PURPOSE

This study was aimed at assessing the incidence and timing of thyroid nodules recurrence, defined as appearance of new benign or malignant nodules in contralateral lobe in patients with benign thyroid nodules or thyroid microcarcinoma treated with lobo-isthmectomy. Patient's characteristics and risk factors associated with this phenomenon were also investigated.

METHODS

A retrospective study was performed by evaluating 413 patients undergoing lobo-isthmectomy with a minimum follow-up of 1 year. Clinical characteristics, surgical interventions and complications, histological diagnosis, and thyroid function at last follow-up were collected.

RESULTS

Single or multiple thyroid nodule recurrence equally occurred in 80 patients (23%) with a median time to relapse of ~ 5 years (range 0.3-34.5 years) after lobo-isthmectomy. Recurrence was significantly associated with younger age (< 46 years) and number of pregnancies in women. Development of hypothyroidism was not rare either (~ 10%) and appeared in 3-19 months; a preoperative TSH level > 2.43 mIU/L was associated with the need of l-thyroxin replacement therapy after surgery. The most frequent surgical complication was transient hypoparathyroidism (4.6%), while the rate of permanent hypoparathyroidism significantly increased in patients submitted to completion thyroidectomy (5.3%).

CONCLUSIONS

Thyroid nodules recurrence following lobo-isthmectomy is not a rare event and occurs within 5 years after surgery, more frequently in younger patients with family history of nodular goiter and in women with multiple pregnancies. Pre-surgical TSH levels may predict the development of post-surgical hypothyroidism, possibly improving the management of patients addressed to surgery.

Outcomes of Radiofrequency Ablation Therapy for Large Benign Thyroid Nodules: A Mayo Clinic Case Series

OBJECTIVE

To assess the effectiveness, tolerability, and complications of radiofrequency ablation (RFA) in patients with benign large thyroid nodules (TNs).

PATIENTS AND METHODS

This is a retrospective review of 14 patients with predominantly solid TNs treated with RFA at Mayo Clinic in Rochester, Minnesota, from December 1, 2013, through October 30, 2016. All the patients declined surgery or were poor surgical candidates. The TNs were benign on fine-needle aspiration, enlarging or causing compressive symptoms, and 3 cm or larger in largest diameter. We evaluated TN volume, compressive symptoms, cosmetic concerns, and thyroid function.

RESULTS

Median TN volume reduction induced by RFA was 44.6% (interquartile range [IQR], 42.1%-59.3%), from 24.2 mL (IQR, 17.7-42.5 mL) to 14.4 mL (IQR, 7.1-19.2 mL) (P<.001). Median follow-up was 8.6 months (IQR, 3.9-13.9 months). Maximum results were achieved by 6 months. Radiofrequency ablation did not affect thyroid function. In 1 patient with subclinical hyperthyroidism due to toxic adenoma, thyroid function normalized 4 months after ablation of the toxic nodule. Compressive symptoms resolved in 8 of 12 patients (67%) and improved in the other 4 (33%). Cosmetic concerns improved in all 8 patients. The procedure had no sustained complications.

CONCLUSION

In this population, RFA of benign large TNs performed similarly to the reports from Europe and Asia. It induces a substantial volume reduction of predominantly solid TNs, improves compressive symptoms and cosmetic concerns, and does not affect normal thyroid function. Radiofrequency ablation has an acceptable safety profile and should be considered as a low-risk alternative to conventional treatment of symptomatic benign TNs.

Comparison of the Efficacy of Three Different Methods of Explaining the Surgical Procedure of Hemithyroidectomy

BACKGROUND

For patients indicated for surgical treatment, adequate information about the procedure and its complications is a prerequisite for consent, reassures the patient, and allows them to make a well-informed decision. This prospective randomized study aimed to compare the outcomes of three different methods of explaining the procedure of hemithyroidectomy to patients' satisfaction.

MATERIAL AND METHODS

The three different methods for explaining the surgical procedure included a conventional diagram, three-dimensional (3D) thyroid model, and 2-minute animated video. A modified Patient Satisfaction Questionnaire was used to evaluate the efficacy of the methods and assess overall patient experience; 20 patients were randomized to each group. An endocrine surgeon performed the operative procedure using a sutureless technique. The procedure was explained to the patient a week before surgery in the outpatient department.

RESULTS

Majority of the patients were female. The most common indication for surgery was a solitary thyroid nodule. Patients who watched the animated video demonstrated significantly higher satisfaction levels and significantly lower anxiety levels than those in the other groups (P < 0.01). Patients who watched the video or who received instructions using the 3D model also reported that their information needs were met. Overall experience with the procedure and hospital stay was not significantly different between the groups.

CONCLUSION

Overall patient satisfaction for the surgical procedure was similar across the three groups. However, the animated video appeared to be a better model to explain the procedure to the patient, resulting in enhanced knowledge acquisition, reduced anxiety, and improved patient satisfaction.

Subclinical hypothyroidism: new trials, old caveats

The indications for levothyroxine replacement therapy for subclinical hypothyroidism (SH) remain a subject of debate, especially when prescribed for older adults. The results of the recent TRUST trial indicate that levothyroxine does not improve clinical symptom scores among elderly patients with SH. While there is much concern regarding the dilemma of introducing or withholding levothyroxine, less attention may be paid to the differential diagnosis of an elevated TSH level, which is the prerequisite for diagnosing SH. Herein, we review these issues facing endocrinologists and internists/generalists either in practice or in training. When a patient presents abnormal thyroid test results compatible with SH, a series of issues need to be addressed before the implementation of replacement therapy is considered: first, an isolated TSH elevation not linked to a primary thyroid pathology should be excluded; second, the persistent nature of the patient's TSH elevation and SH profile should be verified; third, SH symptoms and potential complications relevant for the specific patient should be documented; fourth, expectations from levothyroxine substitution therapy for SH in the specific patient should be clarified. Only then can the decision be made whether levothyroxine substitution should be introduced or not.

Quality of Life in Patients Treated with Percutaneous Laser Ablation for Non-Functioning Benign Thyroid Nodules: A Prospective Single-Center Study

Objective

While many studies have reported that laser ablation (LA) for benign non-fuctioning thyroid nodules is efficacious in reducing nodular volume and neck symptoms, none have described changes in quality of life (QoL). The purpose of this study was to report post-LA changes in QoL in our cohort of patients.

Materials and Methods

Fourteen patients with benign thyroid nodules were involved in a prospective, single-center study and underwent a single session of LA. We evaluated the following: changes in nodule volume, thyroid function, and autoimmunity; adverse events during and after LA; changes in neck discomfort by means of a visual analogic scale (VAS) at one week and 1, 3, 6, and 12 months; and changes in QoL through the 13-scale Thyroid-specific Patient Reported Outcome (ThyPRO) questionnaire at 1, 3, 6, and 12 months. ThyPRO is a validated questionnaire for thyroid diseases, which consists of 13 scales with multiple-choice answers. They investigate several aspects of life that may be impaired by goiter-related compression symptoms, by esthetic alterations and by hypo- or hyperthyroidism.

Results

Nodule volume decrease was −37 ± 23%, −55 ± 22%, −53 ± 25%, −58 ± 25% (p < 0.01 vs. baseline) at the first, third, sixth, and twelfth month, respectively. No hypothyroidism or positivization of autoimmunity was observed. There were no major complications during or after LA. After LA, VAS scores improved significantly from 1 week onwards in 100% of patients, while a significant improvement was seen in the goiter symptoms score after one month, and in the general score and mean values of ThyPRO after six months. Scores on the other ThyPRO scales did not change significantly.

Conclusion

Laser ablation is safe and effective in reducing nodule volume and neck symptoms; this is confirmed by improvements in the goiter scale, general score, and mean values of ThyPRO and in the VAS score.

Hypothyroidism

Hypothyroidism is a common condition of thyroid hormone deficiency, which is readily diagnosed and managed but potentially fatal in severe cases if untreated. The definition of hypothyroidism is based on statistical reference ranges of the relevant biochemical parameters and is increasingly a matter of debate. Clinical manifestations of hypothyroidism range from life threatening to no signs or symptoms. The most common symptoms in adults are fatigue, lethargy, cold intolerance, weight gain, constipation, change in voice, and dry skin, but clinical presentation can differ with age and sex, among other factors. The standard treatment is thyroid hormone replacement therapy with levothyroxine. However, a substantial proportion of patients who reach biochemical treatment targets have persistent complaints. In this Seminar, we discuss the epidemiology, causes, and symptoms of hypothyroidism; summarise evidence on diagnosis, long-term risk, treatment, and management; and highlight future directions for research.

Controversies in the Management of Low-Risk Differentiated Thyroid Cancer

Controversy exists over optimal management of low-risk differentiated thyroid cancer. This controversy occurs in all aspects of management, including surgery, use of radioactive iodine for remnant ablation, thyroid hormone supplementation, and long-term surveillance. Limited and conflicting data, treatment paradigm shifts, and differences in physician perceptions contribute to the controversy. This lack of physician consensus results in wide variation in patient care, with some patients at risk for over- or undertreatment. To reduce patient harm and unnecessary worry, there is a need to design and implement studies to address current knowledge gaps.

High-intensity focused ablation (HIFU) of single benign thyroid nodule rarely alters underlying thyroid function

BACKGROUND

High intensity focused ultrasound (HIFU) is a promising ablation technique for benign thyroid nodules. However, its effect on underlying thyroid function remains unknown. We aimed to evaluate the 6 months changes in serum thyroid stimulating hormone (TSH) and free thyroxine (FT4) after HIFU treatment.

METHODS

Eighty-three consecutive patients who underwent single HIFU ablation for symptomatic benign thyroid nodule were analysed. Eligible patients had serum TSH and FT4 checked before treatment (baseline), 1 week, 3 and 6 months following HIFU treatment. Primary endpoints were hypothyroidism (FT4 < 12 pmol/L) and hyperthyroidism (FT4 > 23 pmol/L) in the 6 months following treatment. To express extent of nodule ablation relative to the total gland volume, an ablation volume ratio was calculated by [(Ablated nodule volume/total thyroid volume)/(total thyroid volume)] × 100.

RESULTS

Relative to baseline, 1-week serum TSH significantly dropped (from 1.16 to 0.76 mIU/L, p < 0.001) while 1-week serum FT4 significantly rose (from 16.0 to 17.8 pmol/L, p < 0.001). However, 3- and 6-months TSH and FT4 did not changed significantly from baseline (p > 0.05). No patients developed hyperthyroidism while one (1.4%) developed hypothyroidism (FT4 = 11 pmol/L) at 3 months and 6 months. Interestingly, this patient had a previous lobectomy and an ablation volume ratio of 64.00%.

CONCLUSIONS

Hypothyroidism following single HIFU ablation occurred rarely (1.4%) and resulted in little clinical relevance. Given that only one patient developed hypothyroidism following single HIFU ablation, it remains unclear how patients with different amount of parenchyma and relative extent of ablation may affect subsequent thyroid function.

Clinical Features of Early and Late Postoperative Hypothyroidism After Lobectomy

CONTEXT

Lobectomy is preferred in thyroid cancer to decrease surgical complications and avoid lifelong thyroid-hormone replacement. However, postoperative hypothyroidism, requiring thyroid-hormone replacement, may occur.

OBJECTIVE

We aimed to identify the incidence and risk factors of postoperative hypothyroidism to develop a surveillance strategy after lobectomy for papillary thyroid microcarcinoma (PTMC).

METHODS

This historical cohort study involved 335 patients with PTMC treated by lobectomy. Postoperative thyroid functions were measured regularly, and patients were prescribed levothyroxine according to specific criteria. Patients not satisfying hormone-replacement criteria were closely followed up.

RESULTS

Postoperative hypothyroidism occurred in 215 patients (64.2%) including 5 (1.5%) with overt hypothyroidism and 210 (62.7%) with subclinical hypothyroidism. Forty patients (11.9%) were required thyroid hormone replacement. One hundred nineteen patients (33.5%) experienced temporary hypothyroidism and spontaneously recovered to euthyroid state. High preoperative thyroid-stimulating hormone (TSH) was the most important factor predicting postoperative hypothyroidism and failure of recover from hypothyroidism (odds ratio [OR], 2.82 and 1.77; 95% confidence interval [CI], 2.07 to 3.95 and 1.22 to 2.63; P < 0.001 and 0.002, respectively). Of the 215 patients eventually developing postoperative hypothyroidism, 70 (32.6%) developed hypothyroidism after the first postoperative year. Postoperative 1-year TSH levels were able to differentiate patients developing late hypothyroidism or euthyroidism (OR, 2.29; 95% CI, 1.68 to 3.26; P < 0.001).

CONCLUSIONS

Preoperative and postoperative TSH levels might be predictive for patients who develop postlobectomy hypothyroidism and identify those requiring long-term surveillance for hypothyroidism. Additionally, mild postoperative hypothyroidism cases should be followed up without immediate levothyroxine replacement with the expectation of spontaneous recovery.

2017 Guidelines of the American Thyroid Association for the Diagnosis and Management of Thyroid Disease During Pregnancy and the Postpartum

BACKGROUND

Thyroid disease in pregnancy is a common clinical problem. Since the guidelines for the management of these disorders by the American Thyroid Association (ATA) were first published in 2011, significant clinical and scientific advances have occurred in the field. The aim of these guidelines is to inform clinicians, patients, researchers, and health policy makers on published evidence relating to the diagnosis and management of thyroid disease in women during pregnancy, preconception, and the postpartum period.

METHODS

The specific clinical questions addressed in these guidelines were based on prior versions of the guidelines, stakeholder input, and input of task force members. Task force panel members were educated on knowledge synthesis methods, including electronic database searching, review and selection of relevant citations, and critical appraisal of selected studies. Published English language articles were eligible for inclusion. The American College of Physicians Guideline Grading System was used for critical appraisal of evidence and grading strength of recommendations. The guideline task force had complete editorial independence from the ATA. Competing interests of guideline task force members were regularly updated, managed, and communicated to the ATA and task force members.

RESULTS

The revised guidelines for the management of thyroid disease in pregnancy include recommendations regarding the interpretation of thyroid function tests in pregnancy, iodine nutrition, thyroid autoantibodies and pregnancy complications, thyroid considerations in infertile women, hypothyroidism in pregnancy, thyrotoxicosis in pregnancy, thyroid nodules and cancer in pregnant women, fetal and neonatal considerations, thyroid disease and lactation, screening for thyroid dysfunction in pregnancy, and directions for future research.

CONCLUSIONS

We have developed evidence-based recommendations to inform clinical decision-making in the management of thyroid disease in pregnant and postpartum women. While all care must be individualized, such recommendations provide, in our opinion, optimal care paradigms for patients with these disorders.