Benefits of thyrotropin suppression versus the risks of adverse effects in differentiated thyroid cancer

Clinical inertia in thyrotropin suppressive therapy for low-risk differentiated thyroid cancer: A real-world experience at an endocrine center in Bangkok

The management of low-risk differentiated thyroid cancer (DTC) has evolved over time toward treatment de-escalation. However, overtreatment with supraphysiological dose of levothyroxine (LT4) continues to be observed despite current clinical guideline. This study aimed to assess the actual thyrotropin suppressive therapy for low-risk DTC patients at an endocrine center in Bangkok. This retrospective study included patients with low-risk DTC who were regularly follow-up for at least 18 months at Theptarin Hospital between 2016 and 2022. The serum thyroid stimulating hormone (TSH) levels were stratified as TSH < 0.1 mIU/L; TSH 0.1 to 0.5 mIU/L; TSH 0.5 to 2.0 mIU/L; and TSH > 2.0 mIU/L. The initial risk stratification (IRS) and dynamic risk stratification were determined at 12 months of follow-up after completing the initial treatment and at the last visit. The clinical factors associated with overtreatment with LT4 were analyzed. A total of 102 patients (83.3% female, age at diagnosis 41.8 ± 13.6 years, mean tumor size 1.6 ± 1.0 cm) were evaluated with a mean follow-up of 5.9 years. The IRS classified 92.2% of patients after the initial treatment and 93.1% of patients at the last follow-up visit into the excellent response category. The mean LT4 daily dosage at the last follow-up was 121.3 ± 44.8 µg/day. Serum TSH levels were in an appropriate target range according to IRS in only 8.8% (9/102) of the patients and then improved to 19.6% (20/102) at the last follow-up visit. Further analysis showed that treating physicians with ≥10 years of practice was associated with severe TSH suppression therapy (TSH < 0.1 mIU/L). Despite the current clinical guideline recommendations and scientific evidences, less than one-fifth of low-risk DTC patients achieved the appropriate serum TSH target. While the proportion of an optimum LT4 suppressive had improved during the study period, further efforts are needed to overcome this clinical inertia.

The Effect of Thyrotropin Suppression on Survival Outcomes in Patients with Differentiated Thyroid Cancer: A Systematic Review and Meta-Analysis

Background: Long-term management of intermediate- and high-risk differentiated thyroid cancer (DTC) involves thyrotropin (TSH) suppression with thyroid hormone to prevent potential stimulation of TSH receptors on DTC cells, leading to tumor growth. However, the current guidelines recommending TSH suppression are based on low- to moderate-quality evidence. Methods: We performed a systematic review and meta-analysis of studies evaluating the role of TSH suppression in intermediate- and high-risk DTC patients (≥18 years) treated as per regional guideline-based therapy with a follow-up duration of 5 years (PROSPERO #252396). TSH suppression was defined as "below normal reference range" or, when known, <0.5 mIU/L. Primary outcome measures included (i) composite of progression-free survival (PFS), disease-free survival (DFS), and relapse-free survival (RLFS), and (ii) composite of disease-specific survival (DSS), and overall survival (OS). Secondary outcome included a composite of cardiac or skeletal adverse events. All outcomes and comparisons were represented as TSH suppression versus TSH nonsuppression. Randomized controlled trials, cohort studies, and case-control studies were included for analysis. Pooled hazard ratio (HR) and 95% confidence interval (CI) were calculated using random-effects model. Results: Abstract screening was performed on 6,369 studies. After the exclusion of irrelevant studies and full-text screening, nine studies were selected for the final meta-analysis. Based on seven studies (3,591 patients), the composite outcome of PFS, DFS, and RLFS was not significantly different between TSH suppression and nonsuppression groups (HR: 0.75; 95% CI: 0.48-1.17; I2 = 76%). Similarly, a DSS and OS composite outcome assessment based on four studies (3,616 patients) did not favor TSH suppression (HR: 0.69; 95% CI: 0.31-1.52; I2 = 88%). Even after excluding studies of lower quality, the primary outcomes were not significantly different between the TSH suppression and nonsuppression cohorts. The secondary outcome, obtained from two studies (1,294 patients), was significantly higher in the TSH-suppressed groups (HR: 1.82; 95% CI: 1.30-2.55; I2 = 0%). Significant study heterogeneity was noted for primary outcomes. Conclusion: TSH suppression in intermediate- and high-risk DTC may not improve survival outcomes but may increase the risk of secondary complications. However, the limited evidence and study heterogeneity warrant cautious interpretation of our findings. Registration: PROSPERO #252396.

Mcl-1 mediates intrinsic resistance to RAF inhibitors in mutant BRAF papillary thyroid carcinoma

Papillary thyroid carcinoma (PTC) is the most frequent form of thyroid cancer. PTC commonly presents with mutations of the serine/threonine kinase BRAF (BRAFV600E), which drive ERK1/2 pathway activation to support growth and suppress apoptosis. PTC patients often undergo surgical resection; however, since the average age of PTC patients is under 50, adverse effects associated with prolonged maintenance therapy following total thyroidectomy are a concern. The development of mutant-selective BRAF inhibitors (BRAFi), like vemurafenib, has been efficacious in patients with metastatic melanoma, but the response rate is low for mutant BRAF PTC patients. Here, we assay the therapeutic response of BRAFi in a panel of human PTC cell lines and freshly biopsied patient samples. We observed heterogeneous responses to BRAFi, and multi-omic comparisons between susceptible and resistant mutant BRAF PTC revealed overrepresented stress response pathways and the absence of compensatory RTK activation - features that may underpin innate resistance. Importantly, resistant cell lines and patient samples had increased hallmarks of failed apoptosis; a cellular state defined by sublethal caspase activation and DNA damage. Further analysis suggests that the failed apoptotic phenotypes may have features of "minority mitochondrial outer membrane permeabilization (MOMP)" - a stress-related response characterized by fragmented and porous mitochondria known to contribute to cancer aggressiveness. We found that cells presenting with minority MOMP-like phenotypes are dependent on the apoptotic regulator, Mcl-1, as treatment with the Mcl-1 inhibitor, AZD5991, potently induced cell death in resistant cells. Furthermore, PI3K/AKT inhibitors sensitized resistant cells to BRAFi; an effect that was at least in part associated with reduced Mcl-1 levels. Together, these data implicate minority MOMP as a mechanism associated with intrinsic drug resistance and underscore the benefits of targeting Mcl-1 in mutant BRAF PTC.

Five-Year Follow-Up of Health-Related Quality of Life in Differentiated Thyroid Cancer Patients Treated with Total Thyroidectomy and Radioiodine in Sweden: A Nationwide Prospective Cohort Study

Background: Despite a good prognosis, survivors of differentiated thyroid cancer (DTC) may have reduced health-related quality of life (HRQOL) many years after treatment, and it is unclear how suppression of thyroid-stimulating hormone (TSH) may contribute to HRQOL. This study investigated changes in HRQOL in the 5 years following DTC treatment, the association between HRQOL and TSH suppression, and how HRQOL compares to the general population. Methods: In this nationwide prospective cohort study, 487 patients with DTC were identified between 2012 and 2017 from all Swedish hospitals treating patients with DTC. Patients treated with total thyroidectomy and planned for radioiodine answered the Swedish version of the Short Form-36 Health Survey (SF-36) and a study specific questionnaire at treatment and after 1, 3, and 5 years. Summary measures for physical and mental QOL were derived from the SF-36, and TSH values were collected from patient records. To study changes in HRQOL over time, linear mixed models were fitted on multiply imputed data, with all patients and measurement points included in the model. Results: In total, 351 patients consented to participate in the study. In the 5 years following DTC treatment, physical QOL did not change significantly with time, while mental QOL improved by on average 0.61 (p < 0.001) per year. TSH levels were not predictive of either physical or mental QOL, or their change over time. At 5 years, there was a significant difference in physical and mental QOL compared with the Swedish general population, but effect sizes were small (Cohen's d = 0.29 and -0.21, respectively). The SF-36 domains general health, vitality, social functioning, and mental health were lower at 5 years compared with the general population (difference 8.7-13.3), and these differences were clinically significant. Conclusions: The mental component of HRQOL improves over time following DTC treatment. HRQOL in patients with DTC is not explained by TSH suppression. Although overall differences in physical and mental HRQOL compared with the general population were small 5 years after treatment, several specific psychosocial HRQOL domains were clinically meaningfully reduced. Psychosocial health issues should be screened for during DTC follow-up.

Thyroid Cancer: A Review

Importance

Approximately 43 720 new cases of thyroid carcinoma are expected to be diagnosed in 2023 in the US. Five-year relative survival is approximately 98.5%. This review summarizes current evidence regarding pathophysiology, diagnosis, and management of early-stage and advanced thyroid cancer.

Observations

Papillary thyroid cancer accounts for approximately 84% of all thyroid cancers. Papillary, follicular (≈4%), and oncocytic (≈2%) forms arise from thyroid follicular cells and are termed well-differentiated thyroid cancer. Aggressive forms of follicular cell-derived thyroid cancer are poorly differentiated thyroid cancer (≈5%) and anaplastic thyroid cancer (≈1%). Medullary thyroid cancer (≈4%) arises from parafollicular C cells. Most cases of well-differentiated thyroid cancer are asymptomatic and detected during physical examination or incidentally found on diagnostic imaging studies. For microcarcinomas (≤1 cm), observation without surgical resection can be considered. For tumors larger than 1 cm with or without lymph node metastases, surgery with or without radioactive iodine is curative in most cases. Surgical resection is the preferred approach for patients with recurrent locoregional disease. For metastatic disease, surgical resection or stereotactic body irradiation is favored over systemic therapy (eg, lenvatinib, dabrafenib). Antiangiogenic multikinase inhibitors (eg, sorafenib, lenvatinib, cabozantinib) are approved for thyroid cancer that does not respond to radioactive iodine, with response rates 12% to 65%. Targeted therapies such as dabrafenib and selpercatinib are directed to genetic mutations (BRAF, RET, NTRK, MEK) that give rise to thyroid cancer and are used in patients with advanced thyroid carcinoma.

Conclusions

Approximately 44 000 new cases of thyroid cancer are diagnosed each year in the US, with a 5-year relative survival of 98.5%. Surgery is curative in most cases of well-differentiated thyroid cancer. Radioactive iodine treatment after surgery improves overall survival in patients at high risk of recurrence. Antiangiogenic multikinase inhibitors and targeted therapies to genetic mutations that give rise to thyroid cancer are increasingly used in the treatment of metastatic disease.

Active Surveillance Outcomes of Patients with Low-Risk Papillary Thyroid Microcarcinoma According to Levothyroxine Treatment Status

Background: During active surveillance (AS), serum thyrotropin (TSH) levels may affect papillary thyroid microcarcinoma (PTMC) progression. We investigated AS outcomes according to whether levothyroxine (LT4) treatment was administered. Patients and Methods: From 2005 to 2019, 2896 patients with low-risk PTMC underwent AS. Of these, 2509 patients were included: 2187 patients did not receive LT4 at diagnosis (group I), 1935 patients did not receive LT4 during AS (group IA), and 252 patients started LT4 during AS (group IB). The remaining 322 patients were administered LT4 before or at diagnosis (group II). The tumor volume doubling rate (TVDR) and tumor size based on ultrasound examination results and time-weighted detailed TSH scores were calculated. Disease progression was defined as tumor enlargement ≥3 mm and/or the appearance of novel lymph node metastasis. Results: At diagnosis, group II had more high-risk features, such as younger age and larger tumors, than group I. However, group II had a lower disease progression rate (2.9% at 10 years) than group I (6.1%) (p = 0.091). The disease progression rate of group IB (13.8% at 10 years) was significantly higher than that of groups IA (5.0%) and II (2.9%) (p < 0.01). The TVDR of group IB before LT4 administration was significantly higher than that of groups IA and II (0.095 per year, -0.0085 per year, and -0.057 per year, respectively; p < 0.01), suggesting that patients with progression signs during AS were selectively prescribed LT4. The time-weighted detailed TSH score of group IB significantly decreased after LT4 administration compared with those before administration (3.35 and 3.05, respectively; p < 0.01). The TVDR also decreased from 0.13 per year to 0.036 per year (p = 0.08). The proportions of patients with rapid or moderate growth decreased significantly after LT4 (from 26.8% to 12.5%, p < 0.01). A multivariable analysis revealed group IB status was independently associated with disease progression (odds ratio [OR] = 3.42 [CI 2.15-5.44], p < 0.01), whereas age ≥40 years and <60 years and age ≥60 years were independently negatively associated with this outcome (OR = 0.23 [CI 0.14-0.38, p < 0.01 and OR = 0.16 [CI 0.10-0.27], p < 0.01). Conclusion: LT4 treatment may be associated with decreased tumor growth during AS of PTMC, but further confirmatory research is needed.

Progranulin promoted the proliferation, metastasis, and suppressed apoptosis via JAK2-STAT3/4 signaling pathway in papillary thyroid carcinoma

BACKGROUND

Progranulin (PGRN), a glycoprotein secreted by a wide range of epithelial cells and plays an important role in inflammatory mechanisms and tumor progression. In this study, the expression, and functions of PGRN in papillary thyroid carcinoma (PTC) was examined to explore the potential pathogenesis of PTC.

METHODS

Western blotting and qRT-PCR were used to detect the relationship between PGRN expression and clinicopathological characteristics of patients with PTC. PTC cell lines with PGRN overexpression and with PGRN knockdown were established to explore their effects on the biological behavior. Western blotting was used to detect the changes of relevant molecules and JAK2-STAT3/4 signaling pathway. Moreover, rescue experiments validated the involvement of the JAK2-STAT3/4 signaling pathway. And statistical analyses were analyzed using SPASS 21.0 and graph generation were performed using GraphPad Prism 8.0.

RESULTS

PGRN was overexpressed in PTC tissue and increased by 75% at mRNA level and 161% at relative protein level in the patients with lymph node metastasis compared to without lymph node metastasis. Besides, PGRN regulated and promoted PTC cell proliferation, migration, invasion, and inhibited cell apoptosis. With PGRN overexpressed, relevant molecules including the expression of BCL2/BAX, BCL2/BAD, CyclinD1, MMP2, vimentin and N-cadherin were increased, the expression level of E-cadherin was decreased, and the phosphorylation of JAK2 and STAT3/4 were increased. JAK inhibitor (JSI-124) rescued these changes of PTC cells induced by overexpressed PGRN.

CONCLUSIONS

These findings revealed that PGRN promote the progression of PTC through the JAK2-STAT3/4 pathway, and PGRN could be served as a potential therapeutic target for PTC.

Association Between Thyroid-Stimulating Hormone Level and Bell's Palsy

OBJECTIVE

To investigate whether dysregulated thyroid hormone function is associated with Bell's palsy.

STUDY DESIGN

Cross-sectional.

SETTING

Electronic medical record database of Clalit Health Services (CHS). CHS is an Israeli payer-provider, integrated health care system, serving >4.5 million members (54% of the Israeli population).

PATIENTS

Older than 18 years with Bell's palsy, during 2002 to 2019.

INTERVENTIONS

None.

METHODS

A total of 1,374 patients with Bell's palsy who had thyroid-stimulating hormone (TSH) blood levels measured up to 60 days before the palsy were matched (1:2) for age and sex with 2,748 controls who had TSH blood levels and no history of Bell's palsy.

RESULTS

Retrospective review of the CHS database, from 2002 to 2019 yielded 11,268 patients with Bell's palsy, of which, 1,374 met the inclusion criteria. Mean age was 57.9 years, and 61.4% were female. A higher percentage of patients in the Bell's palsy group had low TSH (≤0.55 mIU/L) compared with controls (5.7% vs. 3.6%, p < 0.001). Low TSH compared with TSH > 0.55 mIU/L, was independently associated with 1.45-fold increased odds for having Bell's palsy (95% CI 1.11-2.02, p < 0.001), when controlled for age, sex, body mass index, diabetes, hypertension, prior cerebrovascular accident, hemoglobin level, and purchasing thyroid hormone drugs. Among the patients with TSH ≤ 0.55 mIU/L, 95.5% had normal free thyroxin and 97.7% had normal free triiodothyronine levels (subclinical hyperthyroidism). For 47.1% of patients, TSH remained ≤0.55 mIU/L, 3 to 12 months after the Bell's palsy occurred and most patients had normal free thyroxin (95.4%) and normal free triiodothyronine (91.8%).

CONCLUSIONS

Subclinical hyperthyroidism is independently associated with Bell's palsy after controlling for multiple confounding factors.

Serum Thyrotropin and Triiodothyronine Levels in Levothyroxine-treated Patients

CONTEXT

Small adjustments in levothyroxine (LT4) dose do not appear to provide clinical benefit despite changes in thyrotropin (TSH) levels within the reference range. We hypothesize that the accompanying changes in serum total triiodothyronine (T3) levels do not reflect the magnitude of the changes in serum TSH.

OBJECTIVE

This work aims to characterize the relationships of serum free thyroxine (FT4) vs T3, FT4 vs TSH, and FT4 vs the T3/FT4 ratio.

METHODS

This cross-sectional, observational study comprised 9850 participants aged 18 years and older treated with LT4 from a large clinical database from January 1, 2009, to December 31, 2019. Patients had been treated with LT4, subdivided by serum FT4 level. Main outcome measures included model fitting of the relationships between serum FT4 vs TSH, FT4 vs T3, and FT4 vs T3/FT4. Mean and median values of TSH, T3, and T3/FT4 were calculated.

RESULTS

The relationships T3 vs FT4 and TSH vs FT4 were both complex and best represented by distinct, segmented regression models. Increasing FT4 levels were linearly associated with T3 levels until an inflection point at an FT4 level of 0.7 ng/dL, after which a flattening of the slope was observed following a convex quadratic curve. In contrast, increasing FT4 levels were associated with steep declines in TSH following 2 negative sigmoid curves. The FT4 vs T3/FT4 relationship was fit to an asymptotic regression curve supporting less T4 to T3 activation at higher FT4 levels.

CONCLUSION

In LT4-treated patients, the relationships between serum FT4 vs TSH and FT4 vs T3 across a range of FT4 levels are disproportionate. As a result, dose changes in LT4 that robustly modify serum FT4 and TSH values may only minimally affect serum T3 levels and result in no significant clinical benefit.

Chromatin-Accessible miRNA Regulons Driving Thyroid Tumorigenesis and Progression

BACKGROUND

Although papillary thyroid cancer can remain indolent, associated lymph node metastases and recurrence rates are approximately 50% and 20%, respectively. Omics-based medicine has led to the discovery of predictive biomarkers that can be used to predict tumor progression and clinical outcomes. We aimed to develop a noninvasive omics-driven blood test to allow accurate risk stratification and help tailor individual patient treatment plans.

STUDY DESIGN

RNA sequencing (seq) and microRNA analysis of The Cancer Genome Atlas and Gene Expression Omnibus datasets were employed to identify an epigenetic prognostic panel. Integrated bulk assay for transposase-accessible chromatin-seq and RNA-seq experiments confirmed the results. Sixty-two paired tumor and adjacent control thyroid tissues and 67 blood samples (62 papillary thyroid cancer and 5 controls) were analyzed for validation using sequencing and real-time polymerase chain reaction and correlated to clinical outcomes. A liposome-exosome fusion clustered regularly interspaced short palindromic repeats (CRISPR)-fluorescent detection system miRNA assay was developed. A predictive risk nomogram was generated and tested for performance.

RESULTS

Our miRNA panel (miR-146b-5p and miR-221-3p) from tissue and blood was associated with aggressive features and was located within accessible chromatin regions. The miRNA risk score and prognostic nomogram showed higher accuracy in predicting lymph node metastases (miR-146b: area under the curve [AUC] 0.816, sensitivity 76.9%; miR-221: AUC 0.740, sensitivity 79.5%) and recurrence (miR-146b: AUC 0.921, sensitivity 75.0%; miR-221: AUC 0.756, sensitivity 70.0%; p < 0.001) than staging and American Thyroid Association risk stratification. CRISPR-based miRNA assays showed upregulation in the blood of cancer cohorts.

CONCLUSIONS

CRISPR-based detection of miR-146b and miR-221 in the blood of thyroid cancer patients is a reliable and noninvasive tool for real-time assessment and prognostication that has great potential to provide a direct impact on the care of these patients.

Outcomes and Trends of Treatments in High-Risk Differentiated Thyroid Cancer

OBJECTIVES

To analyze the variant-specific survival benefits and usage patterns of standardized treatment combinations of surgery (S), radioactive iodine ablation (RAI), and thyroid-stimulating hormone suppression therapy (THST) for high-risk differentiated thyroid cancer.

STUDY DESIGN

Retrospective cohort study.

SETTING

National Cancer Database.

METHODS

The 2004-2017 National Cancer Database was queried for patients receiving definitive surgery for high-risk papillary, follicular, or Hurthle cell thyroid cancer. Cox proportional hazards and Kaplan-Meier analyses assessed for treatment-associated survival.

RESULTS

Of 21,076 cases, 18,214 underwent survival analysis with a mean ± SD age of 50.6 ± 17.1 years (71.3% female). When compared with surgery alone, S + RAI was associated with reduced mortality in papillary (hazard ratio [HR], 0.574; P < .001) and follicular (HR, 0.489; P = .004) thyroid cancer. S + RAI + THST was associated with reduced mortality in papillary (HR, 0.514; P < .001), follicular (HR, 0.602; P = .016), and Hurthle cell (HR, 0.504; P = .021) thyroid cancer. In papillary thyroid cancer, S + RAI (91.3%), S + THST (89.2%), and S + RAI + THST (92.7%) were associated with higher 5-year overall survival rates than surgery (85.4%, all P < .001). Papillary thyroid cancer treatments involving THST were associated with higher 5-year overall survival rates than corresponding regimens without THST (all P < .001). In follicular thyroid cancer, S + RAI (73.9%) and S + RAI + THST (78.7%) were associated with higher 5-year overall survival rates than surgery (65.6%, all P < .05). In Hurthle cell thyroid cancer, S + RAI (66.5%) and S + RAI + THST (73.4%) were associated with higher 5-year overall survival rates than surgery (53.7%, all P < .05). On linear regression, THST usage increased by 77.5% (R² = 0.944, P < .001), while RAI usage declined by 11.3% (R² = 0.320, P = .035).

CONCLUSIONS

High-risk differentiated thyroid cancer exhibited varying susceptibilities to different treatment combinations depending on histology, with greatest responses to regimens that included RAI. Physician practices have trended toward decreased RAI and increased THST usage.

Evaluation of Adrenal Reserve in Patients with Differentiated Thyroid Cancer Receiving Thyroid Hormone Suppression Therapy- case-control Comparative Study

BACKGROUND

Patients with differentiated thyroid cancer (DTC) are exposed to subclinical exogenous hyperthyroidism for the suppression of thyroid-stimulating hormone (TSH). In this study, we aimed to evaluate the adrenal reserve in DTC patients receiving suppression therapy.

MATERIALS AND METHODS

The study included 55 DTC patients on suppression therapy and 32 healthy volunteers. Basal serum cortisol of all participants and adrenocorticotropic hormone (ACTH) of the patient group were measured. A standard-dose ACTH test (0.25 mg) was performed in patients with a basal cortisol <14.5 mcg/dL.

RESULTS

In the patient group, TSH was lower, free thyroxine (fT4) was higher, and free triiodothyronine (fT3) was similar to those of the control group (p < .01, p < .01, p = .140, respectively). The serum cortisol of the patient group was significantly lower than the control group (12.14 ± 5.12 mcg/dL vs 18.00 ± 5.56 mcg/dL, p < .001). A total of 34 (61.8%) patients with DTC had a basal cortisol <14.5 mcg/dL. Prolonged TSH suppression (≥5 years vs <5 years) was associated with lower basal cortisol (7.46 ± 2.63 mcg/dL vs 9.48 ± 2.65 mcg/dL, p = .022). The ACTH stimulation test showed that 2 (5.8%) patients had a cortisol response <18 mcg/dL. The rate of adrenal insufficiency was 3.6% in DTC patients. A moderate negative correlation was found between ACTH and fT3 of patients with low basal cortisol (r = -0.358, p = .038).

CONCLUSION

Patients with DTC receiving TSH suppression therapy are at risk for adrenal insufficiency. The duration and severity of suppression might increase this possibility. Dynamic testing with synthetic ACTH can be used to reveal insufficient cortisol response in case of clinical suspicion.

Current Controversies in Low-Risk Differentiated Thyroid Cancer: Reducing Overtreatment in an Era of Overdiagnosis

CONTEXT

Low-risk differentiated thyroid cancer (DTC) is overdiagnosed, but true incidence has increased as well. Owing to its excellent prognosis with low morbidity and mortality, balancing treatment risks with risks of disease progression can be challenging, leading to several areas of controversy.

EVIDENCE ACQUISITION

This mini-review is an overview of controversies and difficult decisions around the management of all stages of low-risk DTC, from diagnosis through treatment and follow-up. In particular, overdiagnosis, active surveillance vs surgery, extent of surgery, radioactive iodine (RAI) treatment, thyrotropin suppression, and postoperative surveillance are discussed.

EVIDENCE SYNTHESIS

Recommendations regarding the diagnosis of DTC, the extent of treatment for low-risk DTC patients, and the intensity of posttreatment follow-up have all changed substantially in the past decade. While overdiagnosis remains a problem, there has been a true increase in incidence as well. Treatment options range from active surveillance of small tumors to total thyroidectomy followed by RAI in select cases. Recommendations for long-term surveillance frequency and duration are similarly broad.

CONCLUSION

Clinicians and patients must approach each case in a personalized and nuanced fashion to select the appropriate extent of treatment on an individual basis. In areas of evidential equipoise, data regarding patient-centered outcomes may help guide decision-making.

Association between thyroid cancer and cardiovascular disease: A meta-analysis

Objective

To determine the association between thyroid cancer and coronary artery disease, atrial fibrillation, cerebrovascular disease, and cardiovascular disease mortality.

Methods

The PubMed, Embase, and Cochrane Library databases were searched for eligible studies from inception to September 22, 2022. Keywords included "thyroid cancer", "atrial fibrillation", "coronary artery disease", "cerebrovascular disease", and "mortality". Primary outcomes included the incidence of coronary artery disease, cerebrovascular disease, atrial fibrillation, and cardiovascular disease mortality among patients with thyroid cancer. Secondary outcomes included cardiovascular disease events among those with thyroid cancer that received or did not receive radioactive iodine or lenvatinib. Estimates were pooled using fixed- and random-effects meta-analysis.

Results

A total of 771,220 patients who underwent thyroidectomy in 15 studies were included. Risk for cerebrovascular disease (risk ratio [RR] 1.15 [95% confidence interval (CI) 1.10-1.21]) and atrial fibrillation [RR 1.59 (95% CI: 1.45-1.73)] were significantly increased. Risk for coronary artery disease was significantly increased [RR 1.12 (95% CI: 1.08-1.17)] in the common effect model. Cardiovascular disease mortality associated with thyroid cancer was not significant [RR 0.93 (95% CI: 0.59-1.45)]. Radioactive iodine had a neutral effect on cardiovascular disease [RR 1.00 (95% CI: 0.87-1.16)], and there was no beneficial nor harmful effect among different RAI doses.

Conclusions

Thyroid cancer was significantly associated with a higher risk for cerebrovascular disease and atrial fibrillation; however, the hazard risk was not different between patients with and without radioactive iodine treatment. Thyroid cancer treatment should be individualized considering the potential harms and benefits to cardiovascular health.

Thyroid-Stimulating Hormone, Age, and Tumor Size are Risk Factors for Progression During Active Surveillance of Low-Risk Papillary Thyroid Microcarcinoma in Adults

BACKGROUND

Active surveillance (AS) of low-risk papillary thyroid microcarcinoma (PTMC) was initiated at Kuma Hospital in 1993 and is gradually spreading worldwide. We assessed the effect of thyroid-stimulating hormone (TSH) levels on PTMC enlargement in patients on AS.

METHODS

We enrolled 2705 patients with cytologically diagnosed PTMC who had undergone AS between January 2005 and July 2019. Patients with Graves disease were excluded. The median AS period was 5.5 years (range 1.0-15.7 years). Tumor enlargement was defined as a size increase ≥3 mm. Chi-square test, Kaplan-Meier method, log-rank test, Cox proportional hazard, and logistic regression were used to compare variables.

RESULTS

Ninety-two patients (3.4%) experienced tumor enlargement; the 5-, 10-, and 15-year enlargement rates were 3.0%, 5.5%, and 6.2%, respectively. Young age (<40 years, p < 0.001), large tumor size (≥9 mm, p = 0.017), and high detailed TSH score (≥3, higher than the lower normal limit, p = 0.011) were significant factors relating to tumor enlargement in the multivariate analysis. In a subset of patients aged <40 years, a low detailed TSH score (<3) was an independent factor against tumor enlargement (p = 0.039). Only 22 patients (0.8%) experienced novel lymph node metastasis; the 5-, 10-, and 15-year node metastasis rates were very low, at 0.9%, 1.1%, and 1.1%, respectively.

CONCLUSIONS

Young patients with PTMC are more likely to experience tumor growth. Mild TSH suppression to achieve a low normal range may prevent carcinoma enlargement; however, prospective studies are needed to draw more reliable conclusions.

A Novel Pyroptosis-Related Gene Signature for Prediction of Disease-Free Survival in Papillary Thyroid Carcinoma

BACKGROUND

The incidence and recurrence rate of papillary thyroid carcinoma (PTC) are high. Thus, it is critical to accurately identify patients at high risk of recurrence. Pyroptosis is a type of programmed cell death closely related to the progression and prognosis of cancer. However, the role of pyroptosis in PTC remains unclear.

METHODS

Transcriptome data for PTC patients were obtained from The Cancer Genome Atlas database. The expression level of pyroptosis-related genes (PRGs) in PTC and normal tissues was identified. Based on these differentially expressed genes, a risk score model of disease-free survival (DFS) was established using least absolute shrinkage and selection operator Cox regression. In-cluster and quantitative real-time PCR validations were carried out. A nomogram, in combination with clinical factors, was also established. In addition, its relationship with immune characteristics and tumor gene mutations is discussed.

RESULTS

A risk score model with four PRGs, including CASP6, CASP9, IL-18, and NOD1, was established. The samples were divided into high- and low-risk clusters, according to the risk score, revealing significant differences in DFS between the two clusters. A nomogram was established combining age, lymph node metastasis and extrathyroidal extension. The area under the curve (AUC) of predicting one-, five-, and 10-year DFS in PTC patients was 0.745, 0.801, and 0.803, respectively. The low-risk cluster showed higher levels of immune infiltration and immune checkpoint gene expression, while the high-risk cluster demonstrated a higher tumor mutation burden.

CONCLUSION

A predictive DFS model was established, based on PRGs, which may aid in identifying patients at high risk of recurrence. The present study helps to better understand the role of pyroptosis in the progression and prognosis of PTC.

The risk between thyrotropin suppression and bone mineral density in differentiated thyroid cancer

BACKGROUND

The effect of thyroid stimulating endocrine (TSH) suppression medical aid on bone mineral density (BMD) of patients with differentiated thyroid carcinoma (DTC) or differentiated thyroid malignant neoplastic disease is still controversial. Our aim was to investigate the effect of TSH suppression therapy on BMD of patients with DTC.

METHODS

A total of 1651 DTC patients with TSH-suppression medical care were analyzed by RevMan 5.3 software (https://training.cochrane.org/online-learning/core-software/revman/revman-5-download) in the present study. The PubMed and Embase databases were consistently hunted for works revealed through July 29, 2022.

RESULTS

The results indicated that a significant association between femoral bone mineral density (FN-BMD) (P = .02) or lumbar spine bone mineral density (L-BMD) (P = .04) and DTC patients with TSH-suppression therapy. However, the total hip bone mineral density (TH-BMD) was not significantly related to DTC patients with TSH-suppression therapy (P = .11). For premenopausal women, it was shown that TH-BMD (P = .02) or L-BMD (P = .01) were closely related to DTC patients with TSH-suppression therapy. However, there was no relationship between FN-BMD and DTC patients with TSH-suppression therapy (P = .06). For postmenopausal women, TH-BMD was closely related to DTC patients with TSH-suppression therapy (P = .02). It was revealed that there was no significant difference between L-BMD (P = .16) or FN-BMD (P = .26) and DTC patients with TSH-suppression therapy. For men, there was no relationship between FN-BMD (P = .94) or L-BMD (P = .29) and DTC patients with TSH-suppression therapy.

CONCLUSION

Our systematic review has demonstrated that TSH inhibition treatment mainly influence the TH-BMD or L-BMD of the DTC patients who were premenopausal women; the TH-BMD of the DTC patients who were postmenopausal women. In addition, there was no influence on the FN-BMD or L-BMD of the DTC patients who were men.

Evolution of suppressing TSH therapy at diagnosis and in the long-term follow-up in a cohort of differentiated thyroid cancer

INTRODUCTION

To evaluate the adequacy of TSH suppression therapy (TSHst) at the first disease assessment and the last follow-up visit.

METHODS

Retrospective observational study of those patients under follow-up of DTC in a reference hospital.

RESULTS

216 patients (79.2% women) were evaluated, with a mean age 59.0 ± 13.1 years-old and a mean follow-up of 6.9 ± 4.3 years. 88.4% were papillary carcinomas. At diagnosis, 69.2% had a low risk of recurrence (RR) compared to 13.6% with a high RR. Dynamic risk stratification (DRS) classified patients at first disease assessment and the last visit as excellent response (ER) in 60.0% and 70.7%, respectively. Those patients with ER in the first and last follow-up control maintained TSHst in 30.7% and 16.3% of the cases, respectively (p < 0.001). The factors associated with maintaining TSHst at the last control were younger age, higher RR at diagnosis, DRE at follow-up, presence of multifocality and histological vascular invasion (p < 0.05). In a logistic regression analysis adopting tsTSH at follow-up as the dependent variable, exclusively age (β = -0.062; p < 0.001), RR at diagnosis (β = 1.074; p < 0.05) and EDR during follow-up (β = 1.237; p < 0.05) maintained statistical significance.

CONCLUSIONS

Despite the current recommendations, 30.7% of patients with low RR and initial ER are under TSHst. This percentage reduced to 16.3% in those patients with ER after a mean follow-up of 6.9 years. Age, baseline RR, and DRE during follow-up were associated to maintaining tsTSH.

Assesment of attainment of recommended TSH levels and levothyroxine compliance in differentiated thyroid cancer patients

OBJECTIVE

Thyroid-stimulating hormone (TSH) suppression treatment can induce signs and symptoms of hyperthyroidism and hypothyroidism due to inappropriate treatment or poor compliance to the treatment. The current study aimed to investigate TSH levels, frequency of being on target TSH, adherence to levothyroxine (LT4) suppression treatment in differentiated thyroid cancer (DTC) patients after surgery in a multicentric setting.

DESIGN AND PATIENTS

This multicentric cross-sectional study was conducted at 21 medical centres from 12 cities in Turkey. DTC patients followed at least one year in the same center included in the study. Clinical data, serum TSH, free thyroxine (FT4), thyroglobulin (Tg) and anti-Tg levels were recorded during the most recent visit. Body mass index, systolic and diastolic blood pressures, pulse rate were measured. LT4 doses were recorded and doses per kilogram of bodyweight were calculated. Pill ingestion habits recorded and adherence to the therapy were evaluated using the Morisky Medication Adherence Scale and categorized as good, moderate or poor compliant based on their scores. Risk stratification forpredicting the disease persistance and/or reccurence was assessed using the American Joint Committee on Cancer-7th edition thyroid cancer staging calculator. TSH serum concentrations were classified as severe suppression (TSH &lt; 0.01 mU/L), moderate suppression (TSH: 0.01-0.1 mU/L), mild suppression (TSHL 0.1-0.5 mU/L), euthyroid (TSH: 0.5-4 mU/L) and hypothyroid (TSH &gt; 4 mU/L). TSH levels can also be classified as on being on target, under the target, or beyond over the target, according to the American Thyroid Association recommendations.

RESULTS

A group of 1125 patients (F/M: 941/184, 50.7 ± 11.7 years) were included in the study. The mean LT4 daily dosage was 132.4 ± 39.6 mcg/day. TSH levels showed severe suppression in 99 (%8.8) patients, moderate suppression in 277 (%24.6) patients and mild suppression in 315 (%28) patients and euthyroid range in 332 (%29.5) patients and hypothyroid range in 97 (8.6%). TSH levels were in target in 29.2% of the patients 20.4% of the patients were undertreated, 50.4% overtreated. The daily LT4 dose and LT4 dose/kg were significantly higher in the severe suppression group (p &lt; .001, p &lt; .001). According to the Morisky scale, 564 patients (50.1%) were good compliant, 368 patients (32.7%) were moderate compliant, and 193 patients (17.1%) were noncompliant. Patients with poor compliance need a higher dose of LT4 compared to the good compliance group (p &lt; .001). TSH levels of patients with good compliance were 0.67 ± 1.96 mU/L and TSH with poor compliance was 2.74 ± 7.47 mU/L (p &lt; .001). TSH levels were similar in patients on fixed and alternating dosages.

CONCLUSION

In 29.2% of the DTC patients, serum TSH levels were at target levels. Remaining of the study group have TSH levels under or over treatment range, exposing the patient to medication side effects. Majorty of the study group 82.8% have good or moderate adherence to LT4 therapy. Reaching TSH targets requires simplified and applicable guidelines and following the guideline recommendations.

Prospects of Testing Diurnal Profiles of Expressions of TSH-R and Circadian Clock Genes in Thyrocytes for Identification of Preoperative Biomarkers for Thyroid Carcinoma

Thyroid Nodules (TN) are frequent but mostly benign, and postoperative rate of benign TN attains the values from 70% to 90%. Therefore, there is an urgent need for identification of reliable preoperative diagnosis markers for patients with indeterminate thyroid cytology. In this study, an earlier unexplored design of research on preoperative biomarkers for thyroid malignancies was proposed. Evaluation of reported results of studies addressing the links of thyroid cancer to the circadian clockwork dysfunctions and abnormal activities of Thyroid-Stimulating Hormone (TSH) and its receptor (TSH-R) suggested diagnostic significance of such links. However, there is still a gap in studies of interrelationships between diurnal profiles of expression of circadian clock genes and TSH-R in indeterminate thyroid tissue exposed to different concentrations of TSH. These interrelationships might be investigated in future in vitro experiments on benign and malignant thyrocytes cultivated under normal and challenged TSH levels. Their design requires simultaneous measurement of diurnal profiles of expression of both circadian clock genes and TSH-R. Experimental results might help to bridge previous studies of preoperative biomarkers for thyroid carcinoma exploring diagnostic value of diurnal profiles of serum TSH levels, expression of TSH-R, and expression of circadian clock genes.

A miRNA-Based Prognostic Model to Trace Thyroid Cancer Recurrence

Simple Summary

Some thyroid tumors elected for surveillance remain indolent, while others progress. The mechanism responsible for this difference is poorly understood, making it challenging to devise patient surveillance plans. Early prediction is important for tailoring treatment and follow-up in high-risk patients. The aim of our study was to identify predictive markers for progression. We leveraged a highly sensitive test that accurately predicts which thyroid nodules are more likely to develop lymph node metastasis, thereby improving care and outcomes for cancer patients.

Abstract

Papillary thyroid carcinomas (PTCs) account for most endocrine tumors; however, screening and diagnosing the recurrence of PTC remains a clinical challenge. Using microRNA sequencing (miR-seq) to explore miRNA expression profiles in PTC tissues and adjacent normal tissues, we aimed to determine which miRNAs may be associated with PTC recurrence and metastasis. Public databases such as TCGA and GEO were utilized for data sourcing and external validation, respectively, and miR-seq results were validated using quantitative real-time PCR (qRT-PCR). We found miR-145 to be significantly downregulated in tumor tissues and blood. Deregulation was significantly related to clinicopathological features of PTC patients including tumor size, lymph node metastasis, TNM stage, and recurrence. In silico data analysis showed that miR-145 can negatively regulate multiple genes in the TC signaling pathway and was associated with cell apoptosis, proliferation, stem cell differentiation, angiogenesis, and metastasis. Taken together, the current study suggests that miR-145 may be a biomarker for PTC recurrence. Further mechanistic studies are required to uncover its cellular roles in this regard.

Case report: Large follicular thyroid carcinoma with multiple cervical lymph node metastases

Introduction

Follicular thyroid carcinoma (FTC) rarely metastasizes to regional lymph nodes, as they mainly metastasize through hematogenous route; in particular, a large FTC with only lateral lymph node metastasis and without distant metastasis has rarely been reported.

Case report

We present a 66-year-old male patient with a progressively growing thyroid for more than 20 years, causing tracheal compression and narrowing. Neck ultrasonography, computed tomography (CT), magnetic resonance (MR) imaging and positron emission tomography–computed tomography (PET/CT) were carried out to obtain images of the thyroid and surrounding tissues. Total thyroidectomy and cervical lateral and central lymph node dissection were undertaken, and histopathological, and immunohistochemical evaluations and molecular pathology confirmed the diagnosis of FTC with multiple cervical lymph node metastases.

Conclusion

We have reported a rare case of large FTC with diffuse nodal involvement but no distant metastases. We present the thyroid ultrasound, neck CT, MR and whole body PET/CT.

Health Anxiety and Its Relationship to Thyroid-Hormone-Suppression Therapy in Patients with Differentiated Thyroid Cancer

Differentiated thyroid cancer (DTC) has a good prognosis; however, patients often need lifelong follow up, and they face potential side effects. The aim of this study was to investigate health anxiety among DTC patients and its relationship to TSH suppression. In 2020, patients from a previous cohort who were from Stockholm completed the 14-item Short Health Anxiety Inventory (SHAI-14; 0−42; 18 being the threshold for clinical significance) and a study-specific questionnaire. Clinical information was also retrieved from medical records. Linear regression was used to investigate the relationship between the TSH levels and the SHAI-14, while adjusting for potential confounders. In total, 146 (73%) patients were included. A total of 24 respondents (16%) scored 18 or more on the SHAI-14, and the mean score was 11.3. Patients with TSH levels of 0.1−0.5 (mE/L) scored, on average, 3.28 points more (p-value 0.01) on the SHAI-14 compared to patients with TSH levels > 0.5. There was no statistically significant difference between patients with TSH levels < 0.1 and TSH levels > 0.5. Thus, we found no linear relationship between the TSH values and health anxiety. Clinically significant levels of health anxiety are slightly higher than those in the general population, but do not appear to be a major psychiatric comorbidity among patients with DTC.

99Tc-Methylene Diphosphonate Treatment is Safe and Efficacious for Osteoporosis in Postmenopausal Differentiated Thyroid Cancer Patients Undergoing TSH Suppression: A Three-Center Non-Randomized Clinical Study

Objective

To investigate the effects of ⁹⁹Tc-methylene diphosphonate (⁹⁹Tc-MDP) on osteoporosis (OS) in postmenopausal patients with differentiated thyroid cancer (DTC) under thyroid stimulating hormone (TSH) suppression.

Patients and Methods

Patients (n = 142) were divided into two groups: (1) ⁹⁹Tc-MDP (n = 70) and (2) alendronate (n = 72) treatments (NCT 02304757). Bone mineral density (BMD) in the lumbar spine and hip was evaluated by DXA, along with bone turnover markers, safety, and quality of life (QOL) using SF-36 at three time points: before treatment and at 6 and/or 12 months after treatment.

Results

The percentage change of BMD in total lumbar spine or hip showed no significant difference throughout the study (P > 0.025). ⁹⁹Tc-MDP and alendronate treatment alone significantly increased BMD in the lumbar spine, but alendronate treatment also significantly increased BMD in total hip at 6 and 12 months, as compared with the baseline. There were no significant differences in the results of the SF-36 scores between the two treatment groups at any time during the whole study period. ⁹⁹Tc-MDP significantly increased bone formation markers of osteocalcin at 6 and 12 months (P all < 0.05), PINP at 12 months (P = 0.001), and bone resorption markers of β-CTX at 6 and 12 months (p < 0.05) as compared with the alendronate treated group. No adverse event was observed in the ⁹⁹Tc-MDP treatment group compared with alendronate (P = 0.014).

Conclusion

⁹⁹Tc-MDP was as efficacious as alendronate in the improvement of lumbar BMD for DTC patients with OS under TSH stimulation. ⁹⁹Tc-MDP was shown to be safe and improved patients’ QOL.

Thyroid disorders and cardiovascular manifestations: an update

Cardiovascular disease (CVD) remains the leading cause of death worldwide, representing a major health, social, and economic issue. Thyroid disorders are very common and affect >10% of the adult population in total. The aim of this review is to describe the physiologic role of thyroid hormones on cardiovascular system, to present cardiovascular manifestations in patients with thyroid disorders, emphasizing in molecular mechanisms and biochemical pathways, and to summarize current knowledge of treatment options. Thyroid hormone receptors are located both in myocardium and vessels, and changes in their concentrations affect cardiovascular function. Hyperthyroidism or hypothyroidism, both clinical and subclinical, without the indicated therapeutical management, may contribute to the progression of CVD. According to recent studies, even middle changes in thyroid hormones levels increase cardiovascular mortality from 20% to 80%. In more details, thyroid disorders seem to have serious effects on the cardiovascular system via plenty mechanisms, including dyslipidemia, hypertension, systolic and diastolic myocardial dysfunction, as well endothelial dysfunction. On top of clinical thyroid disorders management, current therapeutics focus on younger patients with subclinical hypothyroidism and elderly patients with subclinical hyperthyroidism.

Increased Risk of Type 2 Diabetes in Patients With Thyroid Cancer After Thyroidectomy: A Nationwide Cohort Study

CONTEXT

Abnormal thyroid function after thyroidectomy and subsequent thyroid-stimulating hormone suppression can have detrimental effects on glucose homeostasis in patients with thyroid cancer.

OBJECTIVE

To investigate whether thyroidectomy increases the risk of type 2 diabetes in patients with thyroid cancer and to explore the association between levothyroxine dosage and type 2 diabetes risk.

METHODS

A retrospective population-based cohort study using the Korean National Health Insurance database. We included 36 377 thyroid cancer patients without known diabetes who underwent thyroidectomy between 2004 and 2013. Matched subjects with nonthyroid cancer were selected using 1:1 propensity score matching. The main outcome measure was newly developed type 2 diabetes mellitus.

RESULTS

Patients with thyroid cancer who underwent thyroidectomy had a higher risk of developing type 2 diabetes mellitus than the matched controls (hazard ratio [HR] 1.43, 95% CI 1.39-1.47). Among patients with thyroid cancer, when the second quartile group (in terms of the mean levothyroxine dosage; 101-127 μg/day) was considered the reference group, the risk of type 2 diabetes mellitus increased in the first quartile (<101 μg/day; HR 1.45, 95% CI 1.36-1.54) and fourth quartile groups (≥150 μg/day; HR 1.37, 95% CI 1.29-1.45); meanwhile, the risk decreased in the third quartile group (128-149 μg/day; HR 0.91, 95% CI 0.85-0.97).

CONCLUSION

Patients with thyroid cancer who underwent thyroidectomy were more likely to develop type 2 diabetes mellitus than the matched controls. There was a U-shaped dose-dependent relationship between the levothyroxine dosage and type 2 diabetes mellitus risk.

Optimal Serum Thyrotropin Level for Patients with Papillary Thyroid Carcinoma After Lobectomy

Background: The optimal serum thyrotropin (TSH) level for postlobectomy papillary thyroid carcinoma (PTC) patients is unclear. The objective of this study was to examine the association of TSH and recurrence in postlobectomy patients. Methods: Patients who underwent lobectomy for PTC in a single tertiary hospital from January 2000 to December 2014 were enrolled. The mean TSH of a patient was calculated based on each serum TSH value during follow-up. The reference range of serum TSH was 0.5-4.0 mU/L. Univariate and multivariable analyses were performed with Cox proportional hazards models. Restricted cubic spline (RCS) functions were used to model relationships between mean TSH and recurrence-free survival (RFS). Results: A total of 2297 patients (median age 42 years; 1750 (76.2%) female) were analyzed. Mean TSH below (≤0.5mU/L), in the lower half (0.6-2 mU/L), in the upper half (2.1-4 mU/L), and above (>4 mU/L) the reference range were observed in 668 (29.1%), 1162 (50.6%), 345 (15.0%), and 122 (5.3%) patients, respectively. According to the Cox model and RCS, no association was observed between mean TSH and RFS in the whole cohort, low-risk group and intermediate- to high-risk groups (adjusted p = 0.4737, 0.9314, 0.1859, adjusted p for nonlinear = 0.4589, 0.8622, 0.3010). The only RFS difference observed in the stratified univariate analysis was between patients with mean TSH in the lower half (0.6-2 mU/L, n = 659) and above the reference range (>4 mU/L, n = 68) in the intermediate- to high-risk group (10-year RFS by Kaplan-Meier 84.4% vs. 69.4%, log rank p = 0.011). Conclusions: Mean serum TSH levels are not associated with recurrence. A normal TSH reference range is recommended for postlobectomy PTC patients.

Dyslipidemia Risk in Thyroid Cancer Patients: A Nationwide Population-Based Cohort Study

OBJECTIVE

Thyroid cancer (TC) prevalence has been rapidly increasing. While the relationship between thyroid hormones and lipids has been widely investigated, studies regarding dyslipidemia in patients with TC have been scarce and controversial. We aimed to investigate dyslipidemia risk after TC diagnosis compared to the general population without TC.

METHOD

A population-based prospective study was conducted using data from the Korean National Health Insurance Service-National Sample Cohort Database 2.0 (NHIS-NSC DB 2.0), with health insurance claim data of 1,108,369 subjects between 2002 and 2015. The final study sample comprised 466,735 adult subjects without TC or dyslipidemia diagnoses before the index year, 2009. Bidirectional analyses were performed using prospective and retrospective concepts. In the prospective analysis, Kaplan-Meier estimates were calculated and log-rank tests and univariable and multivariable Cox regression analyses were performed to determine the relationship between TC and dyslipidemia. The retrospective analysis involved 1:5 nested case-control matching based on dyslipidemia status and conditional logistic regression analysis.

RESULTS

No significant difference in dyslipidemia incidence was observed between TC patients and the control group, in either the prospective matched (log-rank P = 0.483) or non-matched (log-rank P = 0.424) analyses, or the retrospective analysis (P = 0.3724). In the prospective analysis, 193 patients after TC diagnosis showed similar risk of developing dyslipidemia with the 466,542 controls during the median 7 years of follow-up (unadjusted hazard ratio [HR], 1.102; 95% confidence interval [CI], 0.878-1.383; adjusted HR, 0.932; 95% CI, 0.707-1.230). Multiple propensity score-adjusted models showed similar results, and 114 patients and 570 matched controls showed an HR of 0.818 (95% CI, 0.598-1.120). In the retrospective comparison of dyslipidemia risk in 170 patients and 277,864 controls, the odds ratio was 0.822 (95% CI, 0.534-1.266).

CONCLUSIONS

Dyslipidemia risk was not significantly different between patients with TC and the general population, in both prospective and retrospective analyses.

Role of thyroid hormone therapy in depressive disorders

PURPOSE

The close association among thyroid metabolism, mood disorders and behavior has long been known. The old and modern uses of thyroid hormones to modulate the expression of depression and bipolar disorder and to improve clinical outcome when used in conjunction with psychotropic medications.

METHODS

A literature search was performed to identify studies investigating the effects of thyroid hormone treatment in patient s with mood disorders.

RESULTS

The successful modification of mood disorders with thyroid hormone underscores the association between endocrine and cerebral systems in these disorders. Thyroid hormones have a profound influence on behavior and appear to be capable of modulating the phenotypic expression of major mood disorders. In fact, there is evidence that triiodothyronine (LT3) may accelerate the antidepressant response to antidepressants, and studies suggest that LT3 also may augment the response to antidepressants in refractory depression. Add-on treatment with supraphysiologic doses of levothyroxine (LT4) has shown efficacy in open-label and in placebo-controlled studies, including in rapid cycling and prophylaxis-resistant bipolar disorder, and with acute refractory uni- or bipolar depression. Functional brain-imaging studies (PET) demonstrated that administration of supraphysiologic LT4 improves depressive symptoms in patients with bipolar depression by modulating cerebral activity in the anterior limbic network.

CONCLUSION

The add-on administration of supraphysiologic doses of LT4 is a promising strategy in patients with refractory bipolar and depressive mood disorders.

Long-term follow-up results of PTMC treated by ultrasound-guided radiofrequency ablation: a retrospective study

OBJECTIVES

To confirm the long-term efficacy and safety of radiofrequency ablation (RFA) for low-risk papillary thyroid microcarcinoma (PTMC).

METHODS

We retrospectively reviewed data of 102 primary papillary thyroid carcinoma patients (82 women, 20 men; mean age: 43 [19] years) treated with radiofrequency ablation and thyroid-stimulating hormone (TSH) suppression therapy before December 2018. All patients were at high surgical risk or refused surgery. They were followed up at 1, 3, 6, 9, and 12 months and every 6-12 months thereafter using ultrasound and contrast-enhanced ultrasound. The volume and volume reduction ratio was calculated. Recurrence and lymph node or distant metastasis were evaluated.

RESULTS

The mean initial tumor diameter was 0.50 (0.29) cm; the mean initial volume was 0.06 (0.09) mL. At 1, 3, 6, 9, 12, 24, 36, 48, and 60 months after RFA, complete resorption rates were 0, 0, 9.8 (10/102), 33.3 (34/102), 91.2 (93/102), 96.1 (98/102), 99 (101/102), 100, and 100%, respectively. Two patients had developed ipsilateral neck lymph node metastasis in regions IV and VI at 30- and 18-month follow-ups, respectively. After RFA, 3/102 patients (2.9%) developed hoarseness-the main side effect. No life-threatening or delayed complications occurred. The TSH value in the initial period was 0.06 (0.02) µIU/mL; the rate of reaching the TSH target was 85.7%. The TSH value at follow-up was 1.47 (0.91) µIU/mL; the compliance rate was 99.3%.

CONCLUSIONS

Ultrasound-guided RFA for PTMC is highly effective and safe. RFA can serve as a minimally invasive treatment for PTMC patients who refuse surgery or active surveillance.

Thyrotropin Suppression for Papillary Thyroid Cancer: A Physician Survey Study

Background: Current guidelines recommend against thyrotropin (TSH) suppression in low-risk differentiated thyroid cancer patients; however, physician practices remain underexplored. Our objective was to understand treating physicians' approach to TSH suppression in patients with papillary thyroid cancer. Methods: Endocrinologists and surgeons identified by thyroid cancer patients from the Surveillance, Epidemiology, and End Results registries of Georgia and Los Angeles were surveyed in 2018-2019. Physicians were asked to report how likely they were to recommend TSH suppression (i.e., TSH <0.5 mIU/L) in three clinical scenarios: patients with intermediate-risk, low-risk, and very low-risk papillary thyroid cancer. Responses were measured on a 4-point Likert scale (extremely unlikely to extremely likely). Multivariable logistic regressions were performed to determine physician characteristics associated with recommending TSH suppression in each of the aforementioned scenarios. Results: Response rate was 69% (448/654). Overall, 80.4% of physicians were likely/extremely likely to recommend TSH suppression for a patient with an intermediate-risk papillary thyroid cancer, 48.8% for a patient with low-risk papillary thyroid cancer, and 29.7% for a patient with very low-risk papillary thyroid cancer. Surgeons were less likely to recommend TSH suppression for an intermediate-risk papillary thyroid cancer patient (odds ratio [OR] = 0.36 [95% confidence interval, CI, 0.19-0.69]) compared with endocrinologists. Physicians with higher thyroid cancer patient volume were less likely to suppress TSH in low-risk and very low-risk papillary thyroid cancer patients (i.e., >40 patients per year, OR = 0.53 [CI 0.30-0.96]; OR = 0.49 [CI 0.24-0.99], respectively, compared with 0-20 patients per year). Physicians who estimated higher likelihood of recurrence were more likely to suppress TSH in a patient with very low-risk papillary thyroid cancer (OR = 2.34 [CI 1.91-4.59]). Conclusions: Many patients with low-risk thyroid cancer continue to be treated with suppressive doses of thyroid hormone, emphasizing the need for more high-quality research to guide thyroid cancer management, as well as better understanding of barriers that hinder guideline adoption.

Effects of thyroid-stimulating hormone suppression after thyroidectomy for thyroid cancer on bone mineral density in postmenopausal women: a systematic review and meta-analysis

OBJECTIVES

We assessed thyroid-stimulating hormone (TSH) suppression effects on bone mineral density (BMD) in postmenopausal women who underwent thyroidectomy.

DATA SOURCES

PubMed, EMBASE, Cochrane Library, Web of Science and SCOPUS were searched from inception to 24 February 2021.

STUDY SELECTION

Case-control studies were included.

DATA EXTRACTION AND SYNTHESIS

Two authors independently reviewed the studies, extracted the data and performed meta-analysis of eligible studies.

RESEARCH DESIGN AND METHODS

Studies evaluating BMD in postmenopausal women with thyroid cancer who had thyroidectomy and levothyroxine therapy were included. Differences in BMD were presented as standardised mean differences (SMDs). Meta-analyses were conducted using a random-effects model.

RESULTS

Analysis of 16 case-control studies (426 patients and 701 controls without thyroid cancer) showed that stringent TSH suppression (TSH <0.10 mIU/L) after thyroidectomy had deleterious effects on the BMD of the lumbar spine in postmenopausal women compared with controls (SMD -0.55; 95% CI -0.99 to -0.10; I²=75.8%). There was no significant difference in patients with moderate TSH suppression (TSH 0.10-0.49 mIU/L). TSH suppression in postmenopausal women was not significantly associated with lower femoral neck BMD. Subgroup analysis of the lumbar spine showed that the association between stringent TSH suppression and lower BMD was consistent among studies with >10 years of follow-up (SMD -0.32; 95% CI -0.50 to -0.14). Subgroup analysis of the femoral neck showed that total thyroidectomy was related to detrimental effects on the BMD of the femoral neck (SMD -0.60; 95% CI -0.89 to -0.31; I²=90.4%), but near-total thyroidectomy was not (SMD 0.00; 95% CI -0.30 to 0.30; I²=55.6%).

CONCLUSIONS

Stringent TSH suppression had deleterious effects on the BMD of the lumbar spine after thyroidectomy in postmenopausal women. Further studies are needed to determine whether stringent TSH suppression after thyroidectomy increases the fracture risk.

Measurements of Bone Health after Thyroid-Stimulating Suppression Therapy in Postmenopausal Women with Differentiated Thyroid Carcinoma: Bone Mineral Density versus the Trabecular Bone Score

Background: Thyroid-stimulating hormone (TSH) suppression therapy is an important treatment modality for differentiated thyroid carcinoma (DTC), but it increases fracture risk. The aim of this study was to evaluate changes in bone mineral density (BMD) and trabecular bone score (TBS) in postmenopausal DTC patients receiving TSH suppression therapy. Methods: A total of 410 postmenopausal DTC patients who underwent thyroidectomy and had at least two dual-energy X-ray absorptiometry measurements, including a preoperative measurement, were included. Patients who had osteoporosis medication for more than 1 year were classified as ‘patients with osteoporosis’. Results: In patients without osteoporosis, the change in %BMD was similar between TSH suppression (−) and (+) groups, while the decrease in %TBS was significantly greater in the TSH suppression (+) group than that of the TSH suppression (−) group. The relative risk of vertebral fracture was decreased by TBS changes but not by BMD changes. In patients with osteoporosis, both BMD and TBS showed significant increases in the TSH suppression (−) group but not in TSH suppression (+) group. At year 4, TBS was significantly lower in the TSH suppression (+) group than that in the TSH suppression (−) group, while BMD showed no difference between groups. Conclusions: TBS may better reflect bone health than BMD in postmenopausal DTC patients with TSH suppression therapy.

Incident atrial fibrillation in patients with differentiated thyroid cancer: a meta-analysis

Differentiated thyroid cancer (DTC) represents the most common form of thyroid neoplasms and is becoming increasingly prevalent. Evidence suggests a possible relationship between DTC diagnosis and subsequent atrial fibrillation (AF). If confirmed, this may present an alarming health risk (AF) in an otherwise condition with a relatively good prognosis (DTC). The aim of this systematic review and meta-analysis is to provide for the first time a pooled estimate of AF incidence in DTC patients in comparison to healthy controls. A detailed search in electronic databases, clinical trial registries and grey literature was performed to identify studies reporting the incidence of AF in DTC patients. Newcastle-Ottawa quality assessment scale was used to assess study quality. We used a random effects (RE) generalized linear mixed model (GLMM) in pooling of individual studies and also calculated a prediction interval for the estimate of a new study. Six observational studies met the eligibility criteria, which included totally 187,754 patients with DTC and 199,770 healthy controls. The median follow-up period was 4.3 to 18.8 years; the incidence rate of AF was 4.86 (95% CI, 3.29 to 7.17, I2 = 96%) cases per 1000 person-years, while the incidence rate ratio was 1.54 (95% CI, 1.44 to 1.65, I2 = 0%, 95% PI, 1.33 to 1.78).This is the first meta-analysis to confirm that patients with DTC are at a high risk for developing AF, which may be attributed to a state of iatrogenic hyperthyroidism due to long-term thyrotropin suppression therapy.

Cause-specific mortality after diagnosis of thyroid cancer: a large population-based study

PURPOSE

The study aimed to disclose mortality pattern and quantitatively evaluate risks for cause-specific mortality among thyroid cancer survivors.

METHODS

We included 173,710 patients from the Surveillance, Epidemiology, and End Results (SEER) database with thyroid cancer diagnosed between 1975 and 2015. Standardized mortality ratio (SMR) was calculated using general US population as the reference. Cumulative incidence function curves were constructed to elaborate crude cause-specific mortality by histology. Cox proportional hazards regression model was adopted to identify predictors for cause-specific mortality, expressed as hazard ratio (HR) and 95% confidence interval (CI).

RESULTS

After a median follow-up of 101 months, 23,040 (13.3%) deaths occurred, of which 29.1% and 21.7% were attributable to thyroid cancer and cardiovascular disease (CVD), respectively. CVD SMRs were 1.14, 1.47, 1.21, and 5.66 in patients with follicular, Hürthle cell, medullary and anaplastic histology, respectively. The adjusted HRs of thyroid cancer-specific mortality were 1.59 (95% CI: 1.46-1.74), 1.87 (95% CI: 1.65-2.12), 3.66 (95% CI: 3.31-4.05), and 12.65 (95% CI: 11.50-13.92) for follicular, Hürthle cell, medullary, and anaplastic histology, respectively, as compared with papillary histology; HRs of CVD-specific mortality were 1.23 (95% CI: 1.12-1.34), 1.27 (95% CI: 1.11-1.46), 1.13 (95% CI: 0.96-1.33), and 1.60 (95% CI: 1.19-2.16), respectively. Older age, male sex, nonwhite race, unmarried status, and advanced stage were independent predictors of CVD-specific mortality, while receiving surgery and radiotherapy were protective against CVD-specific mortality.

CONCLUSIONS

We disclosed distinct mortality patterns by histology and identified predictors of CVD-specific mortality in thyroid cancer survivors, supporting CVD intervention for aggressive thyroid cancer.

Thyroid-stimulating hormone decreases the risk of osteoporosis by regulating osteoblast proliferation and differentiation

BACKGROUND

As the incidence of secretory osteoporosis has increased, bone loss, osteoporosis and their relationships with thyroid-stimulating hormone (TSH) have received increased attention. In this study, the role of TSH in bone metabolism and its possible underlying mechanisms were investigated.

METHODS

We analyzed the serum levels of free triiodothyronine (FT3), free thyroxine (FT4), and TSH and the bone mineral density (BMD) levels of 114 men with normal thyroid function. In addition, osteoblasts from rat calvarial samples were treated with different doses of TSH for different lengths of time. The related gene and protein expression levels were investigated.

RESULTS

A comparison of the BMD between the high-level and low-level serum TSH groups showed that the TSH serum concentration was positively correlated with BMD. TSH at concentrations of 10 mU/mL and 100 mU/mL significantly increased the mRNA levels of ALP, COI1 and Runx2 compared with those of the control (P < 0.05, P < 0.01). Bone morphogenetic protein (BMP)2 activity was enhanced with both increased TSH concentration and increased time. The protein levels of Runx2 and osterix were increased in a dose-dependent manner.

CONCLUSIONS

The circulating concentrations of TSH and BMD were positively correlated with normal thyroid function in males. TSH promoted osteoblast proliferation and differentiation in rat primary osteoblasts.

The Assessment of Ventricular Arrhythmia Indicators Based on Electrocardiography in Patients With Differentiated Thyroid Cancer Followed Up With Levothyroxine Suppression

Levothyroxine suppression therapy (LST) can cause some unfavorable effects on the cardiovascular system in patients with differentiated thyroid cancer (DTC). The aim of this study was to evaluate ventricular arrhythmia predictors based on electrocardiography (ECG) in patients with DTC with LST. The ECG parameters including QT, corrected QT (QTc), Tp-e intervals, Tp-e/QT, and Tp-e/QTC ratios of 265 patients with DTC who met the inclusion criteria were compared with 100 controls. No difference was observed in the number of patients with DTC and controls with prolonged and borderline QTc interval (P = .273). Tp-e interval, Tp-e/QT, and Tp-e/QTc ratios were significantly higher in patients (P = .002, P = .02, P = .003; respectively). Linear regression analysis suggested that male gender was a predictor of higher Tp-e interval, Tp-e/QT, and Tp-e/QTc ratios (β = 4.322, R ² = 0.024, P = .042; β = 0.016, R ² = 0.048, P = .005; β = 0.015, R ² = 0.044, P = .006, respectively). A higher serum fT4 level was found to be associated with a higher Tp-e/QT ratio (β = 0.018, R ² = 0.089, P = .007). Ventricular arrhythmia indicators were found to be higher in patients with DTC with LST. Defining ventricular arrhythmia predictors through ECG, an easily accessible cardiac diagnostic tool, can be potentially useful in raising awareness of the possible cardiac harm of LST.

Surgical indications and clinical management of benign and malignant follicular thyroid tumors: An algorithmic-based approach

The present study retrospectively reviewed the treatment courses and results of patients with follicular thyroid tumors, including carcinomas. In the 5 year study period from April 2015 to March 2020, 797 patients with differentiated thyroid carcinoma and 128 patients with follicular tumors (FTs) received surgery or treatment for distant metastases and recurrence at the Kanagawa Cancer Center (Japan). Of these patients, 73 that were diagnosed with follicular thyroid carcinoma (FTC) were included in the present study. An algorithm used for the application of treatment strategies was assessed. The aim of the present study was to examine patients with FT or FTC who were treated at the Kanagawa Cancer Center to devise appropriate treatment strategies and to evaluate the various treatment outcomes of FTC. Pre-diagnostic serum thyroglobulin and thyroid stimulating hormone levels, follow-up and overall survival (OS) were investigated in the present study. The results revealed that OS was significantly increased in patients with minimally invasive follicular thyroid cancer (MIFTC) compared with widely invasive follicular thyroid cancer (WIFTC) (log-rank test, P=0.017). Additionally, OS was significantly higher in patients without distant metastasis at the first consultation compared with those initially diagnosed with distant metastasis (log-rank test, P=0.023). Although all patients without distant metastasis at the first consultation and those with MIFTC are alive, the 10-year survival rates were 75.3% for patients with WIFTC and 75.6% for those with distant metastasis at the first consultation. The results of the present study suggested that the prognosis of WIFTC was the worst among patients with FTC and distant metastasis, and that total thyroidectomy surgery and radioactive iodine treatment are essential. Additionally, if the disease progresses, prompt inclusion of tyrosine kinase inhibitor therapy is necessary.

Thyrotropin suppression therapy for papillary thyroid carcinoma with a huge recurred neck lymph node

Differentiated thyroid cancer (DTC) originating from thyroid tissue is affected by thyrotropin (TSH). TSH suppression therapy is usually recommended after thyroidectomy in cases of DTC. A 57-year-old woman who harbored a very huge recurred lymph node underwent TSH suppression therapy because of the risk of surgical complications. After TSH suppression, the huge neck lymph node exhibited a response and decreased in size. She had been followed up for 144 months. TSH suppression therapy could be considered as an alternative treatment option in a recurred DTC patient with a high perioperative risk.

Personalized treatment for differentiated thyroid cancer: current data and new perspectives

More conservative and personalized treatment options have been developed in recent years to face the rising diagnosis of low-risk differentiated thyroid carcinoma (DTC). The present review describes the change towards a more risk-adapted management either in the treatment or in the follow-up of DTC. Particular attention is given to the innovations introduced by the latest guidelines for low-risk tumors, starting from the most appropriate extension of surgery up to the postoperative management. The emerging role of active surveillance for low-risk microcarcinoma is discussed, as well as the development of percutaneous strategies in the setting of malignant thyroid disease. The recent use of approved new systemic target therapies for advanced radioiodine refractory thyroid cancer is reported, together with the description of new compounds in trial. Finally, we provide some considerations to improve the risk evaluation in a presurgical setting, especially related to the rising role of genetics, to enable better risk-based cancer management and personalized treatment choices.

Cardiovascular Incidence in 6900 Patients with Differentiated Thyroid Cancer: a Swedish Nationwide Study

INTRODUCTION

To minimize recurrence risk in differentiated thyroid cancer (DTC), TSH is usually lifelong suppressed with levothyroxine. A common consequence of this treatment is subclinical hyperthyroidism which can induce cardiovascular disease (CV). This study's aim was to compare CV incidence in DTC patients with the general population in Sweden.

MATERIALS AND METHODS

All Swedish patients diagnosed with DTC in 1987-2013 were included in the cohort study. Lifelong TSH suppression treatment was assumed to be administered to patients in compliance with prevalent national guidelines. Patients were followed from 1 year after DTC diagnosis until December 31, 2014, death, or migration. The event of interest was hospitalization due to any of the following diseases: atrial fibrillation (AF), cerebrovascular disease, cerebral infarction, ischemic heart disease, ischemic heart attack, and heart failure. Standardized incidence ratios (SIRs) were calculated to compare CV incidence between DTC patients and the general population.

RESULTS

The cohort consisted of 6900 patients with DTC. Hospitalization was increased among DTC patients for AF (SIR 1.66, CI 95% 1.41-1.94), and women faced increased hospitalization for cerebrovascular disease (SIR 1.20 CI 95% 1.04-1.38). Regarding the remaining CV diseases, no consistent difference in SIR between the groups was observed.

CONCLUSION

Compared to the general population, DTC patients have a higher incidence in AF, and female face a slightly higher incidence in cerebrovascular disease. However, there was no difference in hospitalization for other studied CV diseases between DTC patients and the general population.

Self-reported medication adherence in differentiated thyroid cancer survivors: Role of illness perception and medication beliefs

BACKGROUND

To investigate medication adherence (MA) to Levothyroxine in differentiated thyroid cancer survivors and analyze the related factors for nonadherence.

METHODS

The Medication Adherence Report Scale (MARS), Hospital Anxiety and Depression Scale (HAD), Brief Illness Perception Questionnaire (B-IPQ), and Beliefs about Medicines Questionnaire (BMQ) were used to assess MA.

RESULTS

Nonadherence was reported in 77 of 197 patients (39.1%). Socioeconomic status and education levels were found to be significantly related to MA. The HAD scores, all items of B-IPQ, and BMQ were associated with MA and showed a correlation with the MARS scores. The primary predictors of MA were greater confidence in treatment modality (odds ratio [OR]: 0.48, 95% confidence interval (CI): 0.37-0.63) and greater belief that the medication had minimal risk of harm (OR: 3.35, 95% CI: 1.50-7.49).

CONCLUSIONS

Special attention should be paid to educational programs for differentiated thyroid carcinoma patients concerning the effectiveness and low risk of harm of medication in order to improve MA.

Analysis of the strategy of LT4 prescribing and TSH monitoring for thyroid carcinoma after lobectomy

Background

Thyrotropin (TSH) suppression is a critical step in the management of differentiated thyroid carcinoma (DTC). The objectives of this study were to evaluate changes in TSH levels and a strategy of initial levothyroxine (LT4) supplementation for TSH suppression in low-risk differentiated thyroid carcinoma (lr-DTC) patients after lobectomy.

Methods

One hundred and ten patients with lr-DTC who received lobectomy were enrolled. Each of the patients was given 50 µg LT4 immediately after lobectomy and were retrospectively analyzed to evaluate the initial dose of LT4 suppression during the first year of follow-up. Risk factors influencing the TSH trend were also evaluated.

Results

Median TSH levels decreased significantly after lobectomy and the initiation of LT4 suppression and were stable from 3 to 12 months. Three months after lobectomy, 44.9% of patients fell into the newly recommended first TSH goal (0.35 to 2.0 mIU/L). Insufficient suppression (≥2.0 mIU/L) and oversuppression (<0.35 mIU/L) was observed in 9.4% and 45.8% of the patients, respectively. Preoperative TSH ≥2.0 mIU/L and the coexistence of Hashimoto thyroiditis (HT) were risk factors influencing the TSH trend.

Conclusions

The monitoring of TSH could start from 3 months after lobectomy. An initial dose (50 µg) of LT4 could be adequate for initial suppression therapy in most patients. However, individual adjustment of the first dose may be necessary based on preoperative TSH concentration and the presence of HT.

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.

New paradigms in the treatment of low-risk thyroid cancer

INTRODUCTION

Thyroid cancer is the most common endocrine malignancy. Multiple different staging systems have been introduced and used for differentiated thyroid carcinoma (DTC).

AREAS COVERED

In this literature review we provide an overview of the standard options for management of patients with low risk differentiated thyroid cancer.

EXPERT OPINION

Surgery is considered the first and most important step in managing DTC with goal to remove all the malignant foci in order to achieve cure and increase the survival with least chance of recurrence. Many studies have been conducted to determine the best surgical approaches and how aggressive surgeries should be in order to achieve the best outcomes regarding efficacy as well as safety. Radioactive iodine (RAI) therapy has also been a part of the treatment regimen and is used for different purposes with three main goals: post-surgical ablation, adjuvant therapy and persisted/recurrent disease treatment. Radiation therapy, on the other hand, is still not recommended to be used routinely in DTC because of the conflicting data of its benefit.

Trabecular bone deterioration in differentiated thyroid cancer: Impact of long-term TSH suppressive therapy

Background

Conflicting results has been reported regard osteoporosis and fractures in patients with Differentiated Thyroid Cancer (DTC). Our objective was to evaluate the long‐term effects of TSH suppression therapy with Levothyroxine (LT4) on trabecular bone score (TBS) and bone mineral density (BMD) in females with DTC after thyroidectomy.

Methods

About 145 women with resected DTC and receiving long‐term TSH therapy, were stratified according to the degree of TSH suppression. Mean duration of follow‐up was 12.3 ± 6.1 years. BMD and TBS, were assessed using dual‐energy X‐ray absorptiometry (DXA) and TBS iNsight (Med‐Imaps), at baseline (1‐3 months after surgery) and at the final study visit.

Results

In patients stratified by duration of TSH suppression therapy (Group I, 5‐10 years; Group II, >10 years), slight increases from baseline TSH levels were observed. Significant decreases in LS‐BMD and FN‐BMD were seen in patients after >10 years. TBS values were lower in Groups I (1.289 ± 0.122) and II (1.259 ± 0.129) compared with baseline values (P = .0001, both groups). Regarding the degree of TSH suppression, TBS was significantly reduced in those with TSH < 0.1 µU/mL (P = .0086), and not in patients with TSH suppression of 0.1.‐0.5 or >0.5 µU/mL.

Conclusions

We found deterioration of trabecular structure in patients with DTC and TSH suppression therapy below 0.1 µU/mL and after 5‐10 years of follow‐up. Significant changes in BMD according to TSH levels were not observed. Trabecular Bone Score is a useful technique for identifying thyroid cancer patients with risk of bone deterioration.

[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.

Pro-Arrhythmic Signaling of Thyroid Hormones and Its Relevance in Subclinical Hyperthyroidism

A perennial task is to prevent the occurrence and/or recurrence of most frequent or life-threatening cardiac arrhythmias such as atrial fibrillation (AF) and ventricular fibrillation (VF). VF may be lethal in cases without an implantable cardioverter defibrillator or with failure of this device. Incidences of AF, even the asymptomatic ones, jeopardize the patient's life due to its complication, notably the high risk of embolic stroke. Therefore, there has been a growing interest in subclinical AF screening and searching for novel electrophysiological and molecular markers. Considering the worldwide increase in cases of thyroid dysfunction and diseases, including thyroid carcinoma, we aimed to explore the implication of thyroid hormones in pro-arrhythmic signaling in the pathophysiological setting. The present review provides updated information about the impact of altered thyroid status on both the occurrence and recurrence of cardiac arrhythmias, predominantly AF. Moreover, it emphasizes the importance of both thyroid status monitoring and AF screening in the general population, as well as in patients with thyroid dysfunction and malignancies. Real-world data on early AF identification in relation to thyroid function are scarce. Even though symptomatic AF is rare in patients with thyroid malignancies, who are under thyroid suppressive therapy, clinicians should be aware of potential interaction with asymptomatic AF. It may prevent adverse consequences and improve the quality of life. This issue may be challenging for an updated registry of AF in clinical practice. Thyroid hormones should be considered a biomarker for cardiac arrhythmias screening and their tailored management because of their multifaceted cellular actions.