Total thyroidectomy may be more reasonable as initial surgery in unilateral multifocal papillary thyroid microcarcinoma: a single-center experience

The Impact of Total Tumor Diameter on Lymph Node Metastasis and Tumor Recurrence in Papillary Thyroid Carcinomas

(1) Introduction: The impact of multifocality/bilaterality on the prognosis of papillary thyroid carcinoma (PTC) is a matter of debate. In order to clarify this debate, several studies have attempted to identify additional parameters associated with poor prognosis, including total tumor diameter (TTD), in the context of multifocal PTCs. In this context, this study was carried out to investigate the impact of TTD on tumor recurrence and lymph node metastasis (LNM) in PTCs. (2) Materials and Methods: The sample of this single-center retrospective study consisted of 706 patients diagnosed with PTC. TTD was calculated as the sum of the largest diameters of tumor foci in multifocal tumors. The resulting TTDs were grouped into TTDs ≤ 10 mm, TTDs > 10 mm, TTDs ≤ 20 mm, and TTDs > 20 mm, using 10 mm and 20 mm as cutoff values. (3) Results: There was no significant difference between multifocal papillary microcarcinomas (PTMCs) with a TTD of >10 mm and unifocal PTCs with a primary tumor diameter (PTD) of >10 mm except for advanced age and lymphovascular invasion (LVI). In addition, perineural invasion (PNI) and TTD > 10 mm were found to be significant risk factors for LNM, and PNI, TTD > 10 mm, TTD > 20 mm, and bilaterality were found to be significant risk factors for recurrence. LVI, and TTD > 10 mm were found to be independent significant predictors for recurrence, and LVI and extrathyroidal extension (ETE) were found to be independent significant predictors for LNM. (4) Conclusions: Considering TTD > 10 mm in recurrence risk categorization models and adopting a clinical approach that takes into account multifocal PTMCs with TTD > 10 mm along with unifocal PTCs with PTD > 10 mm may be more useful in terms of clinical management of the disease.

Total thyroidectomy versus unilateral lobectomy for unilateral multifocal papillary thyroid carcinoma: systematic review and meta‑analysis

The optimal surgical procedure(s) for unilateral multifocal papillary thyroid carcinomas is currently controversial. As such, the present study aimed to compare the efficacies of total thyroidectomy and lobectomy in patients with unilateral multifocal papillary thyroid carcinoma. A literature search of the PubMed/Medline, Embase, Web of Science, Cochrane Library, Wan Fang, and Zhi Wang databases for relevant studies, published from inception to October 31, 2022, was performed. Two researchers independently extracted data from the included studies. Lymph node metastasis, vocal fold paralysis, parathyroid injury, postoperative recurrence, and disease-free survival were evaluated. The meta-analysis included 7 studies comprising 1540 patients, of whom 496 and 1044 underwent lobectomy and total thyroidectomy, respectively. Compared with lobectomy, total thyroidectomy resulted in more vocal cord paralysis (odds ratio [OR] 0.35 [95% confidence interval (CI) 0.13 to 0.96]; P = 0.04) and parathyroid injury (OR 0.11 [95% CI 0.03-0.39]; P = 0.001) but with better disease-free survival (OR 0.21 [95% CI 0.09-0.49]; P = 0.000), although vocal cord paralysis and parathyroid injury, in large part, resolved within 1 year after surgery. In addition, there was no difference in postoperative lymph nodes metastasis (OR 0.74 [95% CI 0.13-4.21]; P = 0.737) and postoperative recurrence (OR 2.37 [95% CI 0.42-13.38]; P = 0.33). Excluding studies that deviated from the general trend, total thyroidectomy was beneficial in reducing recurrence. Compared with lobectomy, total thyroidectomy was beneficial in reducing recurrence and disease-free survival and may be considered a more optimal approach for unilateral multifocal papillary thyroid carcinoma.

Risk factors associated with preferential lateral lymph node metastasis in papillary thyroid carcinoma

BACKGROUND

Lateral lymph node metastasis (LLNM) is common in patients with papillary thyroid cancer (PTC), usually occurring after central lymph node metastasis (CLNM). However, some patients experience LLNM without first developing CLNM. This study aimed to identify the risk factors for developing LLNM without CLNM.

METHODS

We retrospectively reviewed 421 patients diagnosed with PTC who underwent lobectomy or total thyroidectomy with central and ipsilateral lateral lymph node dissection. We collected clinicopathological data and used univariate and multivariate logistic regression analyses to determine the risk factors associated with LLNM without CLNM.

RESULTS

The LLNM without CLNM frequency was 18.3% (77/421). Univariate analyses demonstrated that age over 55 years, primary tumor in the upper portion of the thyroid, the number of central lymph node (CLN) and LLNM, primary tumor size, and the summed size of multi-foci tumors smaller than 1 cm were significantly associated with LLNM without CLNM (p < 0.05). Multivariate analysis revealed that LLNM without CLNM was more likely to occur in patients aged ≥55 years (odds ratio [OR], 2.309; 95% confidence interval [CI], 1.133-4.704; p = 0.021), and primary tumor in the upper portion of the thyroid (OR, 0.524; 95% CI, 0.295-0.934; p = 0.028).

CONCLUSION

The lymph node metastasis pattern in patients with PTC is not constant. Therefore, surgeons should evaluate the lateral lymph nodes, especially in patients older than 55 years or when the primary tumor is in the upper portion of the thyroid.

A systematic review and meta-analysis comparing tumor progression and complications between radiofrequency ablation and thyroidectomy for papillary thyroid carcinoma

BACKGROUND

Papillary thyroid cancer (PTC) is the most frequent thyroid cancers worldwide. The efficacy and acceptability of radiofrequency ablation (RFA) in the treatment of PTC have been intensively studied. The aim of this study is to focus on extra detailed that may influent for PTC or papillary thyroid microcarcinoma (PTMC).

MATERIALS AND METHODS

We identified a total of 1,987 records of a primary literature searched in PubMed, Embase, Cochrane Library, and Google Scholar by key words, from 2000 to 2022. The outcome of studies included complication, costs, and local tumor progression. After scrutiny screening and full-text assessment, six studies were included in the systematic review. Heterogeneity was estimated using I2, and the quality of evidence was assessed for each outcome using the GRADE guidelines.

RESULTS

Our review enrolled 1,708 patients reported in six articles in the final analysis. There were 397 men and 1,311 women in the analysis. Two of these studies involved PTC and four focused on PTMC. There were 859 patients in the RFA group and 849 patients in the thyroidectomy group. By contrast, the tumor progression of RFA group was as same as that surgical groups [odds ratio, 1.31; 95% CI, 0.52-3.29; heterogeneity (I2 statistic), 0%, p = 0.85]. The risk of complication rates was significantly lower in the RFA group than that in the surgical group [odds ratio, 0.18; 95% CI, 0.09-0.35; heterogeneity (I2 statistic), 40%, p = 0.14].

CONCLUSIONS

RFA is a safe procedure with a certain outcome for PTC. RFA can achieve a good efficacy and has a lower risk of major complications.

Predictive Factors for Bilateral Disease in Papillary Microcarcinoma: A Retrospective Cohort Study

Background: Based on risk stratification, the therapeutic options in papillary microcarcinoma (PTMC) can be active surveillance or surgery. Multifocal tumor occurrence can be decisive in determining the treatment strategy. The objective of this study was to identify risk factors for bilateral tumor occurrence in PTMC to enable individual therapy planning. Methods: A total of 545 PTMC patients who underwent thyroidectomy from 2008 to 2020 were retrieved. Univariate and multivariate analyses were performed to evaluate risk factors for bilateral PTMC. Results: 25.1% (n = 137) of all patients had multifocal PTMC, and 13.2% (n = 72) bilateral PTMC, respectively. In contrast to the maximum tumor size, the total tumor size significantly influenced a bilateral tumor manifestation (median total tumor size 5 mm versus 8.5 mm for bilateral PTMC, p < 0.001). A cut-off level for the total tumor size of >10 mm resulted in a sensitivity and specificity of 29.2% and 94.7%, respectively, in predicting a bilateral tumor manifestation, AUC 0.680 (95% CI, 0.611−0.748, p < 0.001). A cut-off of >4 tumors showed a sensitivity of 99.4% and a specificity of 97.5%, AUC 0.897 (95% CI, 0.870−0.924, p < 0.001) in predicting bilaterality. Conclusion: We could demonstrate for the first time that a total tumor size of >10 mm and more than four tumors significantly increased the risk of bilateral PTMC tumor involvement. These findings enable a risk-adjusted patient treatment.

Multi-omics analysis revealed TEK and AXIN2 are potential biomarkers in multifocal papillary thyroid cancer

BACKGROUND

Papillary thyroid carcinoma (PTC), the most common endocrine cancer, accounts for 80-85% of all malignant thyroid tumors. This study focused on identifying targets that affect the multifocality of PTC. In a previous study, we determined 158 mRNAs related to multifocality in BRAF-mutated PTC using The Cancer Genome Atlas.

METHODS

We used multi-omics data (miRNAs and mRNAs) to identify the regulatory mechanisms of the investigated mRNAs. miRNA inhibitors were used to determine the relationship between mRNAs and miRNAs. We analyzed the target protein levels in patient sera using ELISA and immunohistochemical staining of patients' tissues.

RESULTS

We identified 44 miRNAs that showed a negative correlation with mRNA expression. Using in vitro experiments, we identified four miRNAs that inhibit TEK and/or AXIN2 among the target mRNAs. We also showed that the downregulation of TEK and AXIN2 decreased the proliferation and migration of BRAF ( +) PTC cells. To evaluate the diagnostic ability of multifocal PTC, we examined serum TEK or AXIN2 in unifocal and multifocal PTC patients using ELISA, and showed that the serum TEK in multifocal PTC patients was higher than that in the unifocal PTC patients. The immunohistochemical study showed higher TEK and AXIN2 expression in multifocal PTC than unifocal PTC.

CONCLUSIONS

Both TEK and AXIN2 play a potential role in the multifocality of PTC, and serum TEK may be a diagnostic marker for multifocal PTC.

Optimal Surgical Extent in Patients with Unilateral Multifocal Papillary Thyroid Carcinoma

Multifocality increases the risk of recurrence in patients with papillary thyroid carcinoma (PTC); however, it is unclear whether multifocality justifies more extensive or aggressive surgical treatment. Here, we evaluated the effect of the operative extent on the recurrence-free survival (RFS) of patients with multifocal PTC. Between 2010 and 2019, 718 patients with unilateral multifocal PTC were enrolled; 115 patients (16.0%) underwent ipsilateral thyroid lobectomy, and 606 patients (84.0%) underwent total thyroidectomy. With a mean follow up of 5.2 years, RFS was comparable between the total thyroidectomy and lobectomy groups (p = 0.647) after adjusting for potential confounders. Multivariable Cox regression analysis also demonstrated that the operative extent was not an independent predictor of recurrence (HR 1.686, 95% CI: 0.321-8.852). Subgroup analyses further indicated that both total thyroidectomy and thyroid lobectomy resulted in comparable RFS for multifocal PTC patients with other high-risk factors, including tumor size > 1 cm (p = 0.711), lymph node metastasis (p = 0.536), and intermediate ATA risk of recurrence (p = 0.682). In conclusion, thyroid lobectomy was not associated with the risk of recurrence in patients with multifocal PTCs. Multifocality in PTC may not always require aggressive surgery.

Therapeutic Strategy in Low-Risk Papillary Thyroid Carcinoma - Long-Term Results of the First Single-Center Prospective Non-Randomized Trial Between 2011 and 2015

Optimal therapeutic strategy in low advanced papillary thyroid carcinoma (PTC) is still a matter of debate. The management differs depending on the country. A prospective non-randomized study was performed to evaluate whether less extensive surgery could be a safe, acceptable, and sufficient therapeutic option in PTC cT1N0M0 patients. The present paper summarizes the results of over a 5-year follow-up.

MATERIAL

Our prospective group (PG) treated between 2011 and 2015 consisted of 139 patients with cT1aN0M0 PTC who underwent lobectomy (LT) as initial surgical treatment (PGcT1aN0M0 group) and 102 cT1bN0M0 patients in whom total thyroidectomy (TT) with unilateral central neck dissection (CND) was performed (PGcT1bN0M0). PG was compared with the retrospective group (RG) of patients who underwent TT with bilateral CND between 2004 and 2006: 103 cT1aN0M0 patients (RGcT1aN0M0) and 91cT1bN0M0 (RGcT1bN0M0). The risks of reoperation, cancer relapse and postoperative complications were analyzed.

RESULTS

Only 12 cT1aN0M0 patients (7.6%) withdrew from the trial and underwent TT with bilateral CND. Over 90% of patients accepted less extensive surgery. In 4 cT1aN0M0 cases, TT with CND was performed due to lymph node metastases found intraoperatively. The initial clinical stage according to the TNM/AJCC 7^th edition was confirmed histologically in 77% of cases in PGT1aN0M0 and in 72% in PGT1bN0M0, respectively. 24 PGcT1aN0M0 patients were reoperated on. In this group, cancer lesions in the postoperative histological specimens were found in 8 cases (32%). Five-year disease-free survival (DFS) was excellent. However, no statistically significant differences were found between PG and RG groups (99.3% in PGcT1aN0M0 and 99.0%, in RGcT1aN0M0; p = 0.41 and 98%, in PGcT1bN0M0 and 94.4% in RGcT1bN0M0; p=0.19). No significant differences were observed in the incidence of early paresis of the recurrent laryngeal nerves between PG and RG. However, as predicted, LT completely eliminated the risk of postoperative hypoparathyroidism.

SUMMARY

The results of the prospective clinical trial confirm that less extensive surgery in adequately selected low-advanced PTC patients is both safe and sufficient.

Predicting factors of central lymph node metastases in patients with unilateral multifocal papillary thyroid microcarcinoma

Background

Unilateral multifocal papillary thyroid microcarcinoma (UM-PTMC) is not rare, and the suitable extent of operation is controversial. Total thyroidectomy is associated with a high risk of hypoparathyroidism and recurrent laryngeal nerve injury. Hemithyroidectomy should be considered in patients without lymph node metastases. This study aimed to identify factors predicting central lymph node metastases (CLNM) in patients with UM-PTMC.

Methods

A total of 1,453 patients with thyroid cancer underwent surgery at our hospital from January 2018 to June 2018, and 115 patients with UM-PTMC were selected and assessed retrospectively. The relationship between CLNM and clinicopathologic features of UM-PTMC were analyzed by both univariate and multivariate analyses.

Results

Of the 115 patients with UM-PTMC, CLNM were confirmed by pathology in 57 patients. Univariate and multivariate analyses identified the sum diameter of all tumors (≥1.0 cm) [odds ratio (OR) =2.295; 95% confidence interval (CI): 1.036-5.086; P=0.041] and positive CLNM via ultrasonography (OR =5.882; 95% CI: 1.562-22.153; P=0.009) as independent predictors of CLNM.

Conclusions

CLNM are common in patients with UM-PTMC. The sum diameter of all tumors (≥1.0 cm) and positive CLNM via ultrasonography are independent risk factors for CLNM. Our data should be considered in the decision process relating to performing total thyroidectomy or hemithyroidectomy in patients with UM-PTMC.

The Effect of Prophylactic Central Neck Dissection During Hemithyroidectomy on Locoregional Recurrence in Patients With Papillary Thyroid Carcinoma: A Meta-Analysis

Objectives.

Hemithyroidectomy is commonly performed in patients with low- to intermediate-risk papillary thyroid carcinoma. The purpose of this meta-analysis was to evaluate the effect of prophylactic central neck dissection on locoregional recurrence in patients undergoing hemithyroidectomy.

Methods.

A meta-analysis was performed of full-text publications published in English retrieved from the Embase database.

Results.

The rate of regional recurrence in the central compartment after hemithyroidectomy, with or without prophylactic central neck dissection, was 0.17% and 1.78%, respectively. This difference was statistically significant. Recurrence in the lateral compartment or contralateral thyroid was not affected by prophylactic central neck dissection; the overall rate of recurrence was 1.3% and 5.4%, respectively.

Conclusion.

Prophylactic central neck dissection significantly reduced the risk of recurrence in the central compartment in patients undergoing hemithyroidectomy.

Lymph Node Metastasis and Extrathyroidal Extension in Papillary Thyroid Microcarcinoma in Cyprus: Suspicious Subcentimeter Nodules Should Undergo FNA When Multifocality is Suspected

OBJECTIVE

To determine the prevalence of lymph node (LN) metastasis and extrathyroidal extension (ETE) in patients with papillary thyroid microcarcinoma (PTMC) in Cyprus and to evaluate the role of preoperative ultrasound (U/S) examination.

METHODS

A retrospective study of 102 patients who underwent thyroidectomy for PTMC in a 2-year period. Preoperatively, all patients had a thyroid and neck U/S examination with LN mapping. Tumor size according to the largest diameter, number of foci, LN metastasis, and ETE data was collected from the histopathological report and was compared to the preoperative U/S reports.

RESULTS

LN metastasis was present in 23.5% of patients. 15.7% had central, 3.9% had lateral, and 3.9% had both central and lateral LN metastasis. ETE was present in 27.5% of patients. 21.6% had multifocal disease, and in this group, 40.9% had LN metastasis and 36.4% had ETE. Multifocality (p = 0.03), size of tumor (p = 0.05), and ETE (p ≤ 0.001) were significantly associated with LN metastasis. The prevalence of LN metastasis in multifocal PTMC ≤5 mm was the same with multifocal PTMC >5 mm. The preoperative U/S sensitivity for the suspicious lateral neck and central LN was 100%, and the specificity was 100%. The preoperative U/S sensitivity for nodules suspicious for ETE was 53.6%, and the specificity was 100%.

CONCLUSION

The presence of LN metastasis and ETE in our PTMC patients in Cyprus is frequent. Neck U/S mapping is a highly reliable and accurate tool in identifying metastatic nodes. LN metastasis is associated with ETE and multifocality. Suspicious subcentimeter nodules should undergo FNA irrespective of size when multifocality is suspected.

The optimal surgical approach for papillary thyroid carcinoma with pathological n1 metastases: An analysis from the SEER database

OBJECTIVES/HYPOTHESIS

The definition of large-volume pathologic N1 metastases has been changed in the 2017 version 2 of the National Comprehensive Cancer Network guidelines, leading to a controversy over the optimal surgical approach selection for patients with biopsy-proven papillary thyroid carcinoma (PTC). The aim of this study was to investigate the therapeutic efficacy of total thyroidectomy (TT) and thyroid lobectomy (TL) for these patients.

STUDY DESIGN

Retrospective population-based database analysis.

METHODS

A total of 906 consecutive PTC patients with pathologic N1 metastases (>5 involved nodes with metastases ≤5 mm in the largest dimension) were retrieved from the Surveillance, Epidemiology, and End Results database, and divided into two groups (≤2 mm, >2-5 mm) based on the size of the extent of disease. Overall survival (OS) was then compared between patients treated with TT and TL, followed by Cox proportional hazards regression analysis to explore multiple prognostic factors.

RESULTS

OS favored TT compared with TL in patients with more than five involved nodes and metastases >2 to 5 mm in the largest dimension (P < .05). Cox analysis showed that the TL was not an independent factor associated with poorer OS than TT in these patients (P > .05).

CONCLUSIONS

TT showed better survival than TL for patients with more than five involved nodes and metastases >2 to 5 mm in the largest dimension. For patients with more than five involved nodes and metastases ≤2 mm in the largest dimension, either TT or TL can be recommended because there was no difference in survival.

LEVEL OF EVIDENCE

NA Laryngoscope, 130:269-273, 2020.

Long-Term Outcome after Hemithyroidectomy for Papillary Thyroid Cancer: A Comparative Study and Review of the Literature

Background: The extent of surgery for differentiated thyroid cancer (DTC) remains a controversial issue. Since a less aggressive approach is becoming more predominant, we aim here to study the short- and long-term outcomes of DTC patients after hemithyroidectomy. Methods: From a total of 1252 consecutive papillary thyroid cancer (PTC) patients, 109 treated with hemithyroidectomy and 50 with total thyroidectomy but no I¹³¹ were included. Persistent or recurrent disease was defined based on histopathology, imaging studies, and thyroglobulin levels. Results: Our hemithyroidectomy cohort included females (84.4%), microcarcinomas (81.9%), TNM stage I (95.4%), and a low American Thyroid Association (ATA) recurrence risk (94.5%). At one-year post-treatment, 3.7% had persistent disease (all female, median age 55 years, tumor size 7.5 mm). Recurrent disease was detected in 7.5% of those with excellent response at 1-year. With a follow-up of 8.6 years (1–48), all 109 patients were disease free at last visit, including the 11 patients (10.1%) who received additional treatment. Also, when comparing the hemi- and total thyroidectomy groups no significant differences were found in the rate of persistent and recurrent disease, overall mortality, and disease status at last visit. Conclusions: For properly selected low-risk PTC patients, hemithyroidectomy is a safe treatment option with a favorable long-term outcome.

Multifocality related factors in papillary thyroid carcinoma

BACKGROUND

Papillary thyroid carcinoma (PTC) is the main type of the well-differentiated thyroid carcinomas. Multifocality is regarded as a poor prognostic factor for PTC.

METHODS

Documents of 777 patients who underwent thyroidectomy were reviewed retrospectively. A total of 305 PTC patients were included. Patients with multifocal PTC were included in Group 1, and patients with unifocal PTC were included in Group 2.

RESULTS

There were 165 patients (54.0%) in Group 1 and 140 patients (46%) in Group 2. The pathological mixed variant of PTC was significantly higher in Group 1 (p = 0,005). Lymph node metastasis (LNM) was detected at 9.6% and 3.5% in Group 1 and Group 2, respectively (p = 0,028). Micro PTC rates were 28.4% and 40.7% in Group 1 and Group 2, respectively (p = 0,017). Tumor size and pathologically mixed-type and fine-needle aspiration biopsy (FNAB) results were significantly different between multifocal and unifocal Micro PTC (p < 0.05).

CONCLUSIONS

Multifocality is more frequent in patients with tumors ≥1 cm and mixed-type tumors. LNM is found more often in multifocal tumors. The presence of micropapillary tumors can be predicted preoperatively by ultrasound-guided FNAB. Mixed-type pathology is also a predictive factor for multifocality.

Preoperative injection of carbon nanoparticles is beneficial to the patients with thyroid papillary carcinoma: From a prospective study of 102 cases

BACKGROUND

More surgeons had noticed the importance of carbon nanoparticles (CNs) in protection of parathyroid grand in the surgery of thyroidectomy and central lymph lode dissection, but paid less attention to the injection time. The purpose of this study was to investigate whether preoperative injection of CNs can improve the dissection of lymph nodes (LNs) and protect parathyroid grand (PG) for the patients with papillary thyroid carcinoma (TC).

METHODS

A total of 102 consecutive patients were enrolled into this study from August 2016 to June 2017. All the patients were divided randomly into preoperative group and intraoperative group by the injecting time of the CNs. We compared the patients who had CNs injected into thyroid gland 1 month before surgery with a control group of patients who had CNs injected during the operation. The primary endpoints were operative time, numbers of total LN and metastatic LN, ratio of PG auto-transplantation, parathyroid hormone (PTH) level, and postoperative complications.

RESULTS

We identify 206 PGs and 162 PGs in the preoperative and intraoperative group, respectively, (P = .000) and there was low ratio of auto-transplantation in the preoperative group compared with the intraoperative group (39.3% vs 50.62%, P = .003). We also found that the PTH level in the preoperative group was higher than that of preoperative group (2.60 ± 1.00 vs 2.19 ± 0.72, P = .021), and the operation time in the preoperative group was less than the intraoperative group (60.17 ± 6.28 vs 80.94 ± 7.12, P = .000). Meanwhile pathological results revealed 3 PGs of accidental removal occurred in the preoperative group, whereas 9 PGs of accidental removal occurred in the intraoperative group (P = .039). Also there was no difference in the numbers of total and metastatic LN in the 2 groups (P > .05).

CONCLUSION

Preoperative injection of CNs was safe, and can help protect PG and reduce the difficulty of operation.