Thyroid nodules as a risk factor for thyroid cancer in patients with Graves' disease: A systematic review and meta-analysis of observational studies in surgically treated patients

Using Bedside Spectral Doppler Ultrasound for the Assessment of Patients With Thyrotoxicosis

OBJECTIVE

To assess the bedside utility of Spectral Doppler Ultrasound (SDUS) in the initial evaluation of patients presenting with thyrotoxicosis.

METHODS

This is a retrospective cross-sectional study of patients diagnosed with thyrotoxicosis at an academic outpatient endocrinology clinic from August 2019 to November 2022. The thyroid arteries' peak systolic velocities (PSV) were measured bilaterally using SDUS. PSV ≥40 cm/s in at least a single thyroid artery was considered a reasonable cut-off for Graves' disease and PSV of perinodular artery ≥ 25 cm/s for toxic adenoma.

RESULTS

We identified 73 patients. Mean age ± standard deviation 45.2 ± 16.4 years, 54 (74.0%) were female, 49 (67.1%) were Caucasian, 23 (31.5%) were African American, and 1 (1.4%) was Asian. The confirmed diagnoses were 48 (65.8%) Graves' disease, 13 (17.8%) thyroiditis, four (5.5%) toxic adenoma, four (5.5%) amiodarone-induced thyroiditis type 2, 1 (1.4%) toxic multinodular goiter, 1 (1.4%) had an unremarkable repeat thyroid function testing, and two (2.7%) were unconfirmed. Diagnosis based on the SDUS initial assessment was accurate in 65 (89.0%) of the patients, and it was conclusive and confirmatory during the initial encounter in 55 (75.3%) of the patients before additional testing. A thyroid scan was obtained in nine (12.3%) patients. Incorrectly diagnosed patients were observed in two patients of each of the following categories: Graves' disease, thyroiditis, toxic adenoma, and unconfirmed diagnoses.

CONCLUSIONS

SDUS can be a valuable, efficient, and cost-effective bedside tool in the initial assessment of patients presenting with thyrotoxicosis.

Overweight as a biomarker for concomitant thyroid cancer in patients with Graves' disease

The incidence of concomitant thyroid cancer in Graves' disease varies and Graves' disease can make the diagnosis and management of thyroid nodules more challenging. Since the majority of Graves' disease patients primarily received non-surgical treatment, identifying biomarkers for concomitant thyroid cancer in patients with Graves' disease may facilitate planning the surgery. The aim of this study is to identify the biomarkers for concurrent thyroid cancer in Graves' disease patients and evaluate the impact of being overweight on cancer risk. This retrospective cohort study analyzed 122 patients with Graves' disease who underwent thyroid surgery at Seoul St. Mary's Hospital (Seoul, Korea) from May 2010 to December 2022. Body mass index (BMI), preoperative thyroid function test, and thyroid stimulating hormone receptor antibody (TR-Ab) were measured. Overweight was defined as a BMI of 25 kg/m² or higher according to the World Health Organization (WHO). Most patients (88.5%) underwent total or near-total thyroidectomy. Multivariate analysis revealed that patients who were overweight had a higher risk of malignancy (Odds ratios, 3.108; 95% confidence intervals, 1.196-8.831; p = 0.021). Lower gland weight and lower preoperative TR-Ab were also biomarkers for malignancy in Graves' disease. Overweight patients with Graves' disease had a higher risk of thyroid cancer than non-overweight patients. A comprehensive assessment of overweight patients with Graves' disease is imperative for identifying concomitant thyroid cancer.

Autoimmune Thyroid Disease and Differentiated Thyroid Carcinoma: A Review of the Mechanisms That Explain an Intriguing and Exciting Relationship

Autoimmune thyroid disease is a complex and highly frequent disease, where a wide variety of genetic, epigenetic and environmental factors (among others) come together and interact, and is characterized by the presence of two clinical outcomes: hypothyroidism (in Hashimoto's thyroiditis) and hyperthyroidism (in Graves-Basedow disease). For its part, differentiated thyroid carcinoma (mainly papillary carcinoma) is the most common type of cancer affecting the thyroid (and one of the most prevalent worldwide). An important co-occurrence between autoimmune thyroid disease and differentiated thyroid carcinoma has been documented. In this article, studies that have evaluated possible associations and relationships between autoimmune thyroid disease and differentiated thyroid cancer are systematically described and summarized. To date, the underlying mechanism that explains this association is inflammation; however, the characteristics and designs of the studies evaluated do not yet allow a causal relationship between the two entities to be established. These aspects have made it difficult to establish "causality" in the continuum of the pathogenesis between both conditions.

Characteristics, staging and outcomes of differentiated thyroid cancer in patients with and without Graves' disease

Background

The incidence of thyroid cancer has increased over the last three decades with studies showing incidence of thyroid cancer is higher among patients with Graves' Disease (GD) when compared to Toxic multinodular goiter.1 We conducted a retrospective study to further investigate characteristics and outcomes in patients with thyroid cancer and GD.

Methods

We retrospectively reviewed 62 patients with a diagnosis of Differentiated Thyroid Cancer (DTC). We compared age at diagnosis, type, size of tumor, radioactive iodine (RAI) use, and DTC recurrence amongst patients with GD, non-GD patients. We used Chi-square to test for independence among categorical variables at a nominal level of 0.05; comparison was based on t-test.

Results

Out of 62 patients, 29 patients had GD and DTC (47%). 94% had papillary thyroid cancer. Patients with GD were diagnosed with DTC at a younger age (mean 46 years) in comparison to patients without GD (mean 53 years). There was no difference in the type of DTC. Patients with GD had significantly smaller tumor size (mean size 1.035 cm; p value = 0.002), more Stage 1 and 2 compared to patients without GD (p-value = 0.009). Both groups of patients had similar rates of recurrence on follow up and RAI use.

Conclusion

We found patients with GD had smaller tumor size, early-stage DTC when compared to patients without GD and potentially favorable prognosis. More data is needed to understand whether this is due to pathogenesis like Graves antibodies promoting tumor formation or merely earlier detection of DTC in GD.

Risk and Prognosis of Thyroid Cancer in Patients with Graves' Disease: An Umbrella Review

Graves' disease (GD) is an autoimmune disease considered the most common cause of hyperthyroidism. Some studies have investigated its relationship with the risk and prognosis of developing thyroid cancer. Considering that there is no consensus on the relationship between GD and thyroid cancer risk, this umbrella review aimed to summarize the epidemiologic evidence and evaluate its strength and validity on the associations of GD with thyroid cancer risk and its prognosis. This umbrella review was performed using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. We systematically searched PubMed and Scopus from January 2012 to December 2022. The strength of the epidemiological evidence was graded as high, moderate, or weak by the Measurement Tool to Assess Systematic Reviews (AMSTAR-2). "Strong" evidence was found for the risk of thyroid cancer in GD patients with thyroid nodular disease (OR: 5.30; 95% CI 2.43-12) and for the risk of mortality from thyroid cancer in these patients (OR 2.93, 95% CI 1.17-7.37, p = 0.02), particularly in Europe (OR 4.89; 95% CI 1.52-16). The results of this umbrella review should be interpreted with caution; as the evidence comes mostly from retrospective studies, potential concerns are selection and recall bias, and whether the empirically observed association reflects a causal relationship remains an open question.

Patient outcomes following thyroid surgery for thyrotoxicosis

OBJECTIVE

Total thyroidectomy can be used as a definitive treatment modality for thyrotoxicosis. This study assessed the outcomes of patients treated with surgery at a single secondary care site.

METHOD

A retrospective cohort study was conducted analysing consecutive patients who underwent thyroid surgery for thyrotoxicosis between 24 November 2000 and 26 April 2019 (n = 595).

RESULTS

Total thyroidectomy was performed in 95.4 per cent of patients. Two-thirds of patients had Graves' disease histology. Of patients, 22.8 per cent became transiently hypothyroid whilst on levothyroxine (thyroid hormone replacement therapy). Transient and persistent hypocalcaemia was present in 23.3 per cent and 2.8 per cent of patients respectively. Recurrent laryngeal nerve palsy was transient and persistent in 3.6 per cent and 0.3 per cent respectively. Of patients, 2.5 per cent developed post-operative haematomas that required surgical evacuation in the operating theatre.

CONCLUSION

The overall complication rate for thyroid surgery is higher in thyrotoxic than in euthyroid patients. Compared to other treatment modalities, total thyroidectomy appears to be the most effective, definitive means of managing Graves' disease.

Outcomes of Surgical Treatment for Graves' Disease: A Single-Center Experience of 216 Cases

BACKGROUND

The role of surgery in the treatment of Graves' disease (GD) needs to be revisited. The aims of the present retrospective study were to evaluate the outcomes of the current surgical strategy as a definitive treatment of GD at our center and to explore the clinical association between GD and thyroid cancer.

METHODS

A patient cohort of 216 cases from 2013 to 2020 was involved in this retrospective study. The data of the clinical characteristics and follow-up results were collected and analyzed.

RESULTS

There were 182 female and 34 male patients. The mean age was 43.9 ± 15.0 years old. The mean duration of GD reached 72.2 ± 92.7 months. Of the 216 cases, 211 had been treated with antithyroid drugs (ATDs) and hyperthyroidism had been completely controlled in 198 cases. A total (75%) or near-total (23.6%) thyroidectomy was performed. Intraoperative neural monitoring (IONM) was applied to 37 patients. The failure of ATD therapy (52.3%) was the most common surgical indication, followed by suspicion of a malignant nodule (45.8%). A total of 24 (11.1%) patients had hoarseness after the operation and 15 (6.9%) patients had transient vocal cord paralysis; 3 (1.4%) had this problem permanently. No bilateral RLN paralysis occurred. A total of 45 patients had hypoparathyroidism and 42 of them recovered within 6 months. Sex showed a correlation with hypoparathyroidism through a univariate analysis. A total of 2 (0.9%) patients underwent a reoperation because of hematomas. A total of 104 (48.1%) cases were diagnosed as thyroid cancer. In most cases (72.1%), the malignant nodules were microcarcinomas. A total of 38 patients had a central compartment node metastasis. A lateral lymph node metastasis occurred in 10 patients. Thyroid carcinomas were incidentally discovered in the specimens of 7 cases. The patients with concomitant thyroid cancer had a significant difference in body mass index, duration of GD, gland size, thyrotropin receptor antibodies and nodule(s) detected.

CONCLUSION

Surgical treatments for GD were effective, with a relatively low incidence of complications at this high-volume center. Concomitant thyroid cancer is one of the most important surgical indications for GD patients. Careful ultrasonic screening is necessary to exclude the presence of malignancies and to determine the therapeutic plan.

Long-term management of Graves disease: a narrative review

Graves disease (GD) is the most common cause of hyperthyroidism, accounting for more than 90% of cases in Korea. Patients with GD are treated with any of the following: antithyroid drugs (ATDs), radioactive iodine (RAI) therapy, or thyroidectomy. Most patients begin treatment with ATDs, and clinical guidelines suggest that the appropriate treatment period is 12 to 18 months. While RAI treatment and surgery manage thyrotoxicosis by destroying or removing thyroid tissue, ATDs control thyrotoxicosis by inhibiting thyroid hormone synthesis and preserving the thyroid gland. Although ATDs efficiently control thyrotoxicosis symptoms, they do not correct the main etiology of GD; therefore, frequent relapses can follow. Recently, a large amount of data has been collected on long-term ATDs for GD, and low-dose methimazole (MMZ) is expected to be a good option for remission. For the long-term management of recurrent GD, it is important to induce remission by evaluating the patient's drug response, stopping ATDs at an appropriate time, and actively switching to surgery or RAI therapy, if indicated. Continuing drug treatment for an extended time is now encouraged in patients with a high possibility of remission with low-dose MMZ. It is also important to pay attention to the quality of life of the patients. This review aimed to summarize the appropriate treatment methods and timing of treatment transition in patients who relapsed several times while receiving treatment for GD.

Graves' disease and papillary thyroid carcinoma: case report and literature review of a single academic center

BACKGROUND

Graves' disease (GD) and papillary thyroid cancer (PTC) can be concomitant. The existence of a link between these entities has long been investigated, but a clear correlation hasn't been established. We report a case of GD resistant to medical treatment in which surgery revealed unsuspected PTC and we aim to study the prevalence of PTC in Graves' disease, its clinical characteristics and review of the literature.

CASE PRESENTATION

Report of a 32 yo man who presented with weight loss and was found to be biochemically hyperthyroid. Antibodies were positive. Incremental doses of methimazole provided no improvement in thyroid tests. Hypervascularity and a spongiform nodule were noted on ultrasound. Thyroid uptake and scan showed 70.2% uptake. Thyroidectomy was performed due to inadequate therapeutic response. Pathology revealed PTC with extrathyroidal extension and positive lymph nodes. A retrospective review (2000-2021) and literature review of PTC in GD was performed. Clinical data were reviewed. Statistical analysis was calculated to identify correlations. 243 GD patients had total thyroidectomy at an academic center, 50 (20%) had PTC, 14% were microcarcinomas. 76% of cases were less than 55yo, 82% female, 78% stage 1, PTC diagnosis was incidental in 48%, hyperthyroidism was difficult to treat in 10% and only 2% had recurrence of PTC. There was no correlation between demographic or clinical data.

CONCLUSIONS

Evidence is controversial with some studies showing GD does not affect PTC prognosis. PTC may not be well recognized in GD, pre-operative assessment should consider risk of cancer.

Paediatric thyroidectomy: When and why? A 25-year institutional experience

OBJECTIVE

Thyroidectomy in paediatric patients is relatively uncommon. In this study, we reviewed our experience of thyroidectomy in children and identified risk factors associated with postoperative complications.

METHODS

We performed a retrospective analysis of paediatric patients who had thyroidectomy in our institution between April 1995 and January 2021. Demographic data, preoperative cytological findings, indications of surgery, surgical complications and histological results were analysed.

RESULTS

A total of 87 paediatric patients with 92 thyroidectomy were identified. The indications for surgery were Graves' disease refractory to medical treatments (40.2%), benign thyroid nodules or multinodular goitre (26.4%), thyroid carcinoma (23.0%) and multiple endocrine neoplasm type 2A syndrome (10.3%). Patients presented with thyroid nodules or cervical lymph nodes had a 43.9% risk of malignancy. 66 total thyroidectomy were done with median operation time of 134 min(102-170), while 26 hemi-thyroidectomy were performed (Right side 12/92, Left side 14/92) with median operation time of 65 min(49-102). The median postoperative hospital stay was 2 days(1-4). Intraoperative neck dissection (p = 0.003), drain insertion (p = 0.001) and hypocalcaemia requiring medical treatment (p = 0.004) were associated with longer hospital stay. The median follow-up was 11.3 years (3.0-16.8). 32% patients had immediate postoperative hypocalcaemia and 8% patients had permanent hypoparathyroidism. Transient vocal cord palsy was found in 3 patients(3%) and all resolved within 5-month time upon reassessment direct laryngoscopy. The use of intraoperative recurrent laryngeal nerve monitoring was associated with less vocal cord palsy (p = 0.022). The median disease-free survival was 13.7 years(7.4-17.7) for patients operated for well-differentiated thyroid carcinoma(WDTC). amongst the 9 patients who had prophylactic total thyroidectomy for MEN2A syndrome, 44% were found to have medullary thyroid microcarcinomas on pathology.

CONCLUSIONS

Surgical management of paediatric thyroid disease can be complex. Postoperative hypocalcaemia and vocal cord palsy were usually transient after total thyroidectomy. The use of intraoperative recurrent laryngeal nerve monitoring had resulted in less vocal cord palsy. Long-term disease-free survival of patients with thyroid cancer had been achieved with multi-disciplinary management in our centre.

LEVEL OF EVIDENCE

Retrospective Comparative Study; Level III.

Clinical Characteristics and Prognosis of Coexisting Thyroid Cancer in Patients with Graves' Disease: A Retrospective Multicenter Study

BACKGROUND

The association between Graves' disease (GD) and co-existing thyroid cancer is still controversial and most of the previously reported data have been based on surgically treated GD patients. This study investigated the clinicopathological findings and prognosis of concomitant thyroid cancer in GD patients in the era of widespread application of ultrasonography.

METHODS

Data of GD patients who underwent thyroidectomy for thyroid cancer between 2010 and 2019 in three tertiary hospitals in South Korea (Asan Medical Center, Chonnam National University Hwasun Hospital, and Pusan National University Hospital) were collected and analyzed retrospectively. In the subgroup analysis, aggressiveness and clinical outcomes of thyroid cancer were compared nodular GD and non-nodular GD groups according to the presence or absence of the thyroid nodules other than thyroid cancer (index nodules).

RESULTS

Of the 15,159 GD patients treated at the hospitals during the study period, 262 (1.7%) underwent thyroidectomy for coexisting thyroid cancer. Eleven patients (4.2%) were diagnosed with occult thyroid cancer and 182 patients (69.5%) had microcarcinomas. No differences in thyroid cancer aggressiveness, ultrasonographic findings, or prognosis were observed between the nodular GD and non-nodular GD groups except the cancer subtype. In the multivariate analysis, only lymph node (LN) metastasis was an independent prognostic factor for recurrent/persistent disease of thyroid cancer arising in GD (P=0.020).

CONCLUSION

The prevalence of concomitant thyroid cancer in GD patients was considerably lower than in previous reports. The clinical outcomes of thyroid cancer in GD patients were also excellent but, more cautious follow-up is necessary for patients with LN metastasis in the same way as for thyroid cancer in non-GD patients.

Microcalcifications without a thyroid nodule as the sole sign of papillary thyroid carcinoma

SUMMARY

Our objective is to demonstrate the importance of considering microcalcifications even without evidence of nodules as a potential sign of malignancy. Current guidelines, such as those of the British Thyroid Association, acknowledge the clinical significance of microcalcifications only when found within nodules. In this case, they are considered a suspicious feature, classifying the nodules as U5 (i.e. high risk) where fine-needle aspiration biopsy (FNAB) is warranted, following the high likelihood of cancer in these nodules. In addition, there is a dearth of evidence of ultrasound scan (USS) detection of microcalcifications in the thyroid gland outside of nodules, along with their associated clinical implications. Yet, this clinical manifestation is not so infrequent considering that we do encounter patients in the clinic showing these findings upon ultrasound examination. Three patients who presented to our clinic with thyroid-related symptoms were shown to have areas of microcalcifications without a nodule upon sonographic evaluation of their thyroid gland. These incidentally detected hyperechoic foci were later confirmed to correspond to areas of papillary thyroid carcinoma (PTC) on histopathological examination of resected tissue following thyroidectomy. Four more cases were identified with sonographic evidence of microcalcifications without nodules and given their clinical and other sonographic characteristics were managed with active surveillance instead.

LEARNING POINTS

Echogenic foci known as microcalcifications may be visible without apparent association to nodular structures. Microcalcifications without nodules may not be an infrequent finding. Microcalcifications are frequently indicative of malignancy within the thyroid gland even without a clearly delineated nodule. Empirically, the usual guidelines for the management of thyroid nodules can be applied to the management of microcalcifications not confined to a nodule, but such a finding per se should be classified as a 'high-risk' sign.

Short-Term Outcomes of Surgery for Graves' Disease in Germany

BACKGROUND

Surgical treatment of Graves' disease (GD) has a potentially increased incidence of postoperative hypoparathyroidism, recurrent laryngeal nerve palsy (RLNP) and bleeding. The aim of this study was to evaluate the current extent of surgery for the treatment of GD and its safety as a short-term outcome.

METHODS

Patients who underwent thyroid resection for GD were identified from the prospective StuDoQ/Thyroid registry. Patient data were retrospectively analyzed regarding demographics, surgical procedures and perioperative outcomes. Statistics were performed with Student's t-test or Fisher's exact test and multivariate Cox regression analysis. The level of statistical significance was set at p < 0.05.

RESULTS

A total of 1808 patients with GD with a median age of 44 (range 14-85) years were enrolled in a 25-month period by 78 departments, of which 35.7% (n = 645) had an endocrine orbitopathy and 0.1% (n = 6) had thyrotoxic crisis. Conventional open surgery was used in 98.6% of cases and minimally invasive or remote-access approaches were used in 1.4%. Total thyroidectomy was performed in 93.4% of cases (n = 1688). Intraoperative neuromonitoring (IONM) was used in 98.9% (n = 1789) of procedures. In 98.3% (n = 1777) at least one parathyroid gland was visualized and in 20.7% (n = 375) parathyroids were autografted. The rates of unilateral and bilateral transient RLNP were 3.9% (n = 134/3429 nerves at risk) and 0.1% (n = 4/3429 NAR). The rates of transient RLNP tended to be higher when intermittent IONM was used compared to continuous IONM (4.1% vs. 3.4%, p < 0.059). The rate of transient postoperative hypoparathyroidism was overall 29% (n = 525/1808). Multivariate analysis revealed fewer than 300 thyroid resections and fewer than 15 thyroid resections for GD per year, male sex, BMI > 30, autotransplantation of parathyroid glands and previous bilateral thyroid surgery as independent risk factors for postoperative temporary hypoparathyroidism. Reoperations for bleeding (1.3%) were rare.

CONCLUSION

Total thyroidectomy with IONM is safe and currently the most common surgical therapy for GD in Germany. Postoperative hypoparathyroidism is the major complication which should be focused on.

Familial Aggregation and Heritability of Nonmedullary Thyroid Cancer in an Asian Population: A Nationwide Cohort Study

PURPOSE

The purpose of this work is to assess the extent of familial aggregation of nonmedullary thyroid cancer (NMTC) and the relative risks (RRs) of chronic thyroid diseases and common malignancies in first-degree relatives of NMTC patients.

METHODS

In the National Health Insurance Research database of Taiwan, all eligible individuals in 2016 were analyzed (n = 23 696 659) and the family structures of 38 686 patients diagnosed with NMTC between 1997 and 2016 were identified. The prevalence and RRs of NMTC, chronic thyroid diseases, and common malignancies in individuals with first-degree relatives with NMTC were examined. The accountability of heritability and environmental factors to NMTC susceptibility was estimated using the polygenic liability model.

RESULTS

The prevalence of NMTC was 0.16% in the general population and 0.64% in individuals with first-degree relatives with NMTC. Regarding affected relatives, the RR (95% CI) for NMTC was 20.12 (4.86-83.29) for twins, 6.43 (4.80-8.62) for siblings, 5.24 (4.55-6.03) for offspring, 5.07 (4.41-5.81) for parents, and 2.07 (1.53-2.81) for spouses. The estimated genetic, common environmental, and nonshared environmental contributions to NMTC were 28.0%, 14.3%, and 57.7%, respectively. A family history of NMTC was associated with higher risks of thyroid nodules (RR, 2.26; 95% CI, 2.18-2.35), Hashimoto thyroiditis (2.11; 1.89-2.36), Graves disease (1.49; 1.42-1.57), lung cancer (1.56; 1.32-1.85), and leukemia and lymphoma (1.24; 1.03-1.50).

CONCLUSION

Our findings demonstrate the importance of genetic and environmental contributions to NMTC susceptibility and highlight the coaggregation of chronic thyroid diseases and multiple malignancies with NMTC.

A systematic review of the incidence of thyroid carcinoma in patients undergoing thyroidectomy for thyrotoxicosis

INTRODUCTION

Hyperthyroidism (HT) has been associated with no insignificant rates of thyroid malignancy. There are no current specific guidelines that suggest routine preoperative imaging for thyroid nodules in patients with Grave's disease. We therefore performed a systematic review assessing rates of thyroid malignancy in patients undergoing surgery for different causes of HT: Grave's disease (GD), toxic adenoma (TA) and toxic multinodular goitre (TMNG).

METHODS

Major databases (MEDLINE, PubMed and the Cochrane library) were searched to identify eligible studies.

RESULTS

After searching and appraising, 33 papers were found to be eligible for analysis. The mean overall rate of malignancy was 8.5% (range 0.8%-32.4%). The mean rates based on histological subtype were as follows: papillary thyroid cancer (PTC), 3.1% (range 0%-13.2%); micropapillary carcinoma (mPTC), 5.1% (range 0%-16.9%); and follicular thyroid cancer (FTC), 0.8% (range 0%-4.4%). In those patients who had preoperative imaging, mean malignancy rates were higher in patients with pre-identified nodules (19.8%) compared to those without any nodules (8.7%). Mean rates were lower in patients with GD/diffuse goitre (5.9%) compared to patients with TA (6.5%) and TMNG (12%).

CONCLUSION

Hyperthyroidism is associated with notable rates of thyroid cancer, although the mechanisms for this are not clear. The presence of nodules increases this risk. This review raises the question for considering preoperative assessment of nodules in all patients undergoing surgery for HT, in order to correctly assess and evaluate any patients with suspected concurrent thyroid malignancy, before proceeding with surgery.