Surgeons' Attitudes on Total Thyroidectomy vs Lobectomy for Management of Papillary Thyroid Microcarcinoma

A meta-analysis of total thyroidectomy and lobectomy outcomes in papillary thyroid microcarcinoma

INTRODUCTION

Current research on the most effective surgical method for papillary thyroid microcarcinoma is in dispute. Specifically, whether a total thyroidectomy (TT) is superior to a thyroid lobectomy (LT) in terms of recurrence rate, postoperative complications, and recurrence-free survival is an issue to be addressed. The objective of this study was to compare TT with LT in terms of recurrence, postoperative complications, and recurrence-free survival.

METHODS

In accordance with the Preferred Reporting Items for Systemic Reviews and Meta-Analyses standards, the PubMed, Embase, web of science and the Cochrane Library database were searched for relevant studies comparing TT versus LT. By pooling the relative risks (RR) of the 2 surgical procedures, perioperative results of the 2 group can be estimated. Recurrence-free survival was calculated from hazard ratios between the 2 surgical group.

RESULTS

This meta-analysis included 8 studies involving 16,208 patients. In the TT group, there were fewer recurrences than in the LT group. (RR = 0.68; 95% confidence interval [CI], 0.39 to 1.18; P = .001). In subgroup analyses based on country and sample size, there were no significant differences between the 2 groups for the recurrence rates. We found that patients that underwent LT had lower total complication rates (RR = 15.12; 95% CI, 8.89 to 25.73; P = .009), wound recurrent laryngeal nerve injury and hypocalcemia. In terms of survival, TT can provide better recurrence-free survival than LT, with a hazard ratios of 0.57 (95% CI 0.36 to 0.90; P = .003).

CONCLUSION

Comparing TT with LT, no statistical difference was found in recurrence rates between the 2 groups. In addition, the analysis showed a slight improvement in long-term recurrence-free survival for patients who underwent TT than for those who underwent LT, a finding with potential clinical implications for management decisions on papillary thyroid microcarcinoma treatment.

Risk Factors for Calcium-Phosphate Disorders after Thyroid Surgery

INTRODUCTION

Iatrogenic hypoparathyroidism following thyroidectomy is one of the most common complications significantly reducing patients' quality of life.

OBJECTIVES

This study aimed to analyze the risk factors for calcium-phosphate disorders following thyroidectomy.

PATIENTS AND METHODS

The study group consisted of 211 patients who underwent thyroidectomy for different conditions in 2018-2020. Demographic, clinical and surgical risk factors were analyzed against hypoparathyroidism and hypocalcemia.

RESULTS

Hypoparathyroidism occurred in 15.63% of patients, and hypocalcemia occurred in 45% of those operated on. There was statistical significance between hypoparathyroidism and the extent of thyroid surgery: thyroidectomy vs. lobectomy (p = 0.02, OR = 4.5) and surgeon experience (p = 0.016, OR = 6.9). Low preoperative PTH levels were associated with a higher incidence of hypoparathyroidism (p = 0.055, OR = 0.9). There was a statistically significant correlation between the occurrence of hypocalcemia and preoperative vitamin D deficiency (p = 0.04, OR = 3.5). Low calcium levels before surgery were associated with a higher incidence of hypocalcemia (p = 0.051, OR = 0.5). Meta-analyses of selected risk factors confirmed that the most significant factor in the incidence of hypocalcemia was a decrease in PTH levels (p < 0.001).

CONCLUSIONS

The extent of thyroid surgery and the experience of the surgeon are the most significant risk factors for hypoparathyroidism. Hypocalcemia is much more common than hypoparathyroidism. Among the risk factors for hypocalcemia, in addition to the decrease in parathormone levels due to iatrogenic parathyroid damage, we should mention vitamin D deficiency in the preoperative period.

Eliciting Low-Risk Thyroid Cancer Treatment Preferences using Clinical Vignettes: A Pilot Study

OBJECTIVE

While surgical resection has been the traditional standard treatment for small (≤1 cm), differentiated thyroid cancers, active surveillance and radiofrequency ablation are increasingly considered. The aim of this study was to explore patient preferences in thyroid cancer treatment using a series of clinical vignettes.

METHODS

Thyroid cancer survivors and general population volunteers were recruited to rank experience-driven clinical vignettes in order of preference. Rankings were compared using Wilcoxon signed rank. Formative qualitative methods were used to develop and refine clinical vignettes that captured four treatments-thyroid lobectomy (TL), total thyroidectomy (TT), active surveillance (AS), and radiofrequency ablation (RFA)-along with six treatment complications. Content was validated via interviews with five academic subspecialists.

RESULTS

Nineteen volunteers participated (10 survivors, 9 general population). Treatment complications were ranked lower than uncomplicated counterparts in 99.0% of cases, indicating excellent comprehension. Counter to our hypothesis, among uncomplicated vignettes, median rankings were 1 for AS, 2 for RFA, 3.5 for TL, and 5 for TT. Trends were consistent between thyroid cancer survivors and the general population. Active surveillance was significantly preferred over RFA (p = 0.02) and TT (p <0.01). Among surgical options, TL was significantly preferred over TT (p <0.01).

CONCLUSION

When treatments for low-risk thyroid cancer are described clearly and accurately through clinical vignettes, patients may be more likely to choose less invasive treatment options over traditional surgical resection.

The relative importance of treatment outcomes to surgeons' recommendations for low-risk thyroid cancer

BACKGROUND

The treatment of low-risk thyroid cancer is controversial. We evaluated the importance of treatment outcomes to surgeons' recommendations.

METHODS

A cross-sectional survey asked thyroid surgeons for their treatment recommendations for a healthy 45-year-old patient with a solitary, low-risk, 2-cm papillary thyroid cancer. The importance of the 10 treatment outcomes (survival, recurrence, etc.) to their recommendation was evaluated using constant sum scaling, a method where 100 points are allocated among the treatment outcomes; more points indicate higher importance. The distribution of points was compared between surgeons recommending total thyroidectomy and surgeons recommending lobectomy using Hottelling's T2 test.

RESULTS

Of 165 respondents (74.3% response rate), 35.8% (n = 59) recommended total thyroidectomy and 64.2% (n = 106) lobectomy. The importance of the 10 treatment outcomes was significantly different between groups (P < .05). Surgeons recommending total thyroidectomy were most influenced by the risk of recurrence (19.1 points; standard deviation 16.5) and rated this 1.6-times more important than those recommending lobectomy. Conversely, surgeons recommending lobectomy placed high emphasis on need for hormone replacement (14.3 points; standard deviation 15.4), rating this 3.1-times more important than those recommending total thyroidectomy.

CONCLUSION

Surgeons who recommend total thyroidectomy and those who recommend lobectomy differently prioritize the importance of cancer recurrence and thyroid hormone replacement. Understanding how surgeons' beliefs influence their recommendations is important for ensuring patients receive treatment aligned with their values.

Quasi-Static Mechanical Properties and Continuum Constitutive Model of the Thyroid Gland

The purpose of this study is to obtain the digital twin parameters of the thyroid gland and to build a constitutional model of the thyroid gland based on continuum mechanics, which will lay the foundation for the establishment of a surgical training system for the thyroid surgery robot and the development of the digital twin of the thyroid gland. First, thyroid parenchyma was obtained from fresh porcine thyroid tissue and subjected to quasi-static unconfined uniaxial compression tests using a biomechanical test platform with two strain rates (0.005 s^-1 and 0.05 s^-1) and two loading orientations (perpendicular to the thyroid surface and parallel to the thyroid surface). Based on this, a tensile thyroid model was established to simulate the stretching process by using the finite element method. The thyroid stretching test was carried out under the same parameters to verify the validity of the hyperelastic constitutive model. The quasi-static mechanical property parameters of the thyroid tissue were obtained by a quasi-static unconstrained uniaxial compression test, and a constitutional model that can describe the quasi-static mechanical properties of thyroid tissue was proposed based on the principle of continuum media mechanics, which is of great value for the establishment of a surgical training system for the head and neck surgery robot and for the development of the thyroid digital twin.

Trends in the Management of Localized Papillary Thyroid Carcinoma in the United States (2000-2018)

Background: In response to evidence of overdiagnosis and overtreatment of papillary thyroid carcinoma (PTC), the 2009 and 2015 American Thyroid Association (ATA) adult guidelines recommended less extensive surgery (lobectomy vs. total thyroidectomy) and more restricted use of postsurgical radioactive iodine (RAI) in management of PTC at low risk of recurrence. In 2015, active surveillance was suggested as a viable option for some <1-cm PTCs, or microcarcinomas. The 2015 ATA pediatric guidelines similarly shifted toward more restricted use of RAI for low-risk PTCs. The impact of these recommendations on low-risk adult and pediatric PTC management remains unclear, particularly after 2015. Methods: Using data from 18 Surveillance, Epidemiology, and End Results (SEER) U.S. registries (2000-2018), we described time trends in reported first-course treatment (total thyroidectomy alone, total thyroidectomy+RAI, lobectomy, no surgery, and other/unknown) for 105,483 patients diagnosed with first primary localized PTC (without nodal/distant metastases), overall and by demographic and tumor characteristics. Results: The declining use of RAI represented the most pronounced change in management of PTCs <4 cm (44-18% during the period 2006-2018), including microcarcinomas (26-6% during the period 2007-2018). In parallel, an increasing proportion of PTCs were managed with total thyroidectomy alone (35-54% during the period 2000-2018), while more subtle changes were observed for lobectomy (declining from 23% to 17% during the period 2000-2006, stabilizing, and then rising from 17% to 24% during the period 2015-2018). Use of nonsurgical management did not meaningfully change over time, impacting <1% of microcarcinomas annually during the period 2000-2018. Similar treatment trends were observed by sex, age, race/ethnicity, metropolitan vs. nonmetropolitan residence, and insurance status. For pediatric patients (<20 years), use of RAI peaked in 2009 (59%), then decreased markedly to 11% (2018), while use of total thyroidectomy alone and, to a lesser extent, lobectomy increased. No changing treatment trends were observed for ≥4-cm PTCs. Conclusions: The declining use of RAI in management of low-risk adult and pediatric PTC is consistent with changing recommendations from the ATA practice guidelines. Post-2015 trends in use of lobectomy and nonsurgical management of low-risk PTCs, particularly microcarcinomas, were more subtle than expected; however, these trends may change as evidence regarding their safety continues to emerge.

Is thyroid hormone supplementation avoidable for patients with low-risk papillary thyroid cancer after thyroid lobectomy? A two-center observational study

OBJECTIVE

Changing insights regarding the extent of surgery for low-risk papillary thyroid cancer (PTC) stir up discussions on the benefits and harms of thyroid lobectomy versus total thyroidectomy. The chance of needing postoperative thyroid hormone supplementation after thyroid lobectomy is still unclear. The purpose of this retrospective two-center study was to identify the incidence and risk factors of postoperative thyroid-stimulating hormone (TSH) elevation (>2.0 μIU/ml) after thyroid lobectomy for low-risk PTC.

DESIGN AND METHODS

Medical records of 201 consecutive patients with low-risk PTC from two tertiary centers who underwent thyroid lobectomy between 2015 and 2019 were retrospectively reviewed. Postoperative thyroid function tests were measured regularly and patients were prescribed levothyroxine if the TSH level was higher than 2.0 μIU/ml. Multivariable regression models were used to evaluate potential risk factors associated with postoperative TSH elevation after thyroid lobectomy.

RESULTS

At 6 weeks postoperatively, 85% had TSH level of >2 μIU/ml; this increased to 88% by 3-6 months. Receiver operating characteristic analysis identified preoperative TSH cut-off (>1.7 μIU/ml) to predict postoperative TSH elevation. Multivariate analysis revealed that only a high preoperative TSH level (>1.7 μIU/ml) was an independent risk factor for a postoperative TSH level of >2 μIU/ml (odds ratio = 7.71; p < .001).

CONCLUSION

Nearly 90% of the patients who underwent thyroid lobectomy for low-risk PTC had a postoperative TSH level of >2 μIU/ml, necessitating thyroid hormone supplementation in accordance with current guidelines. This finding highlights that preoperative patient counseling should also focus on raising awareness about postoperative thyroid hormone supplementation for low-risk PTC patients seeking thyroid lobectomy.