Surgical treatment of thyroid follicular neoplasms: results of a retrospective analysis of a large clinical series

Automated diagnosis and management of follicular thyroid nodules based on the devised small-dataset interpretable foreground optimization network deep learning: a multicenter diagnostic study

BACKGROUND

Currently, follicular thyroid carcinoma (FTC) has a relatively low incidence with a lack of effective preoperative diagnostic means. To reduce the need for invasive diagnostic procedures and to address information deficiencies inherent in a small dataset, we utilized interpretable foreground optimization network deep learning to develop a reliable preoperative FTC detection system.

METHODS

In this study, a deep learning model (FThyNet) was established using preoperative ultrasound images. Data on patients in the training and internal validation cohort ( n =432) were obtained from Ruijin Hospital, China. Data on patients in the external validation cohort ( n =71) were obtained from four other clinical centers. We evaluated the predictive performance of FThyNet and its ability to generalize across multiple external centers and compared the results yielded with assessments from physicians directly predicting FTC outcomes. In addition, the influence of texture information around the nodule edge on the prediction results was evaluated.

RESULTS

FThyNet had a consistently high accuracy in predicting FTC with an area under the receiver operating characteristic curve (AUC) of 89.0% [95% CI 87.0-90.9]. Particularly, the AUC for grossly invasive FTC reached 90.3%, which was significantly higher than that of the radiologists (56.1% [95% CI 51.8-60.3]). The parametric visualization study found that those nodules with blurred edges and relatively distorted surrounding textures were more likely to have FTC. Furthermore, edge texture information played an important role in FTC prediction with an AUC of 68.3% [95% CI 61.5-75.5], and highly invasive malignancies had the highest texture complexity.

CONCLUSION

FThyNet could effectively predict FTC, provide explanations consistent with pathological knowledge, and improve clinical understanding of the disease.

Performance of current ultrasound-based malignancy risk stratification systems for thyroid nodules in patients with follicular neoplasms

OBJECTIVES

To investigate the ability of the currently used ultrasound-based malignancy risk stratification systems for thyroid neoplasms (ATA, AACE/ACE/AME, K-TIRADS, EU-TIRADS, ACR-TIRADS and C-TIRADS) in distinguishing follicular thyroid carcinoma (FTC) from follicular thyroid adenoma (FTA). Additionally, we evaluated the ability of these systems in correctly determining the indication for biopsy.

METHODS

Three hundred twenty-nine follicular neoplasms with definitive postoperative histopathology were included. The nodules were categorized according to each of six stratification systems, based on ultrasound findings. We dichotomized nodules into the positive predictive group of FTC (high and intermediate risk) and negative group of FTC based on the classification results. Missed biopsy was defined as neoplasms that were diagnosed as FTCs but for which biopsy was not indicated based on lesion classification. Unnecessary biopsy was defined as neoplasms that were diagnosed as FTAs but for whom biopsy was considered indicated based on classification. The diagnostic performance and missed and unnecessary biopsy rates were evaluated for each stratification system.

RESULTS

The area under the curve of each system for distinguishing follicular neoplasms was < 0.700 (range, 0.511-0.611). The missed biopsy rates were 9.0-22.4%. The missed biopsy rates for lesions ≤ 4 cm and lesions sized 2-4 cm were 16.2-35.1% and 0-20.0%, respectively. Unnecessary biopsy rates were 65.3-93.1%. In ≤ 4 cm group, the unnecessary biopsy rates were 62.2-89.7%.

CONCLUSION

The malignancy risk stratification systems can select appropriate nodules for biopsy in follicular neoplasms, while they have limitations in distinguishing follicular neoplasms and reducing unnecessary biopsy. Specific stratification systems and recommendations should be established for follicular neoplasms.

KEY POINTS

• Current ultrasound-based malignancy risk stratification systems of thyroid nodules had low efficiency in the characterization of follicular neoplasms. • The adopted stratification systems showed acceptable performance for selecting FTC for biopsy but unsatisfactory performance for reducing unnecessary biopsy.

Risk of Complications in Patients Undergoing Completion Thyroidectomy after Hemithyroidectomy for Thyroid Nodule with Indeterminate Cytology: An Italian Multicentre Retrospective Study

Simple Summary

The increasing use of high-quality imaging techniques together with improved access to healthcare has led to an increase in the detection of thyroid nodules. Fine-needle aspiration cytology (FNAC) is currently considered the most accurate examination for the assessment of thyroid nodular disease. However, in about 25% of cases, FNAC leads to the diagnosis of an indeterminate thyroid nodule, which represents a problem because malignancy, although relatively low (up to 30%), cannot be excluded with certainty. According to the 2015 American Thyroid Association guidelines, patients with thyroid nodular disease with an indeterminate cytology can undergo, based on established factors, a total thyroidectomy or a hemithyroidectomy. However, if an intermediate or high-risk differentiated thyroid carcinoma is detected after the hemithyroidectomy, through histological examination, the above-mentioned guidelines recommend performing a completion thyroidectomy. The main aim of this study was to assess the rate of complications in patients undergoing a completion thyroidectomy after a hemithyroidectomy for a thyroid nodule with an indeterminate cytology.

Abstract

There is still controversy as to whether patients undergoing a completion thyroidectomy after a hemithyroidectomy for a thyroid nodule with an indeterminate cytology have a comparable, increased or decreased risk of complications compared to those submitted to primary thyroid surgery. The main aim of this study was to investigate this topic. Patients undergoing a thyroidectomy for thyroid nodular disease with an indeterminate cytology in four high-volume thyroid surgery centres in Italy, between January 2017 and December 2020, were retrospectively analysed. Based on the surgical procedure performed, four groups were identified: the TT Group (total thyroidectomy), HT Group (hemithyroidectomy), CT Group (completion thyroidectomy) and HT + CT Group (hemithyroidectomy with subsequent completion thyroidectomy). A total of 751 patients were included. As for the initial surgery, 506 (67.38%) patients underwent a total thyroidectomy and 245 (32.62%) a hemithyroidectomy. Among all patients submitted to a hemithyroidectomy, 66 (26.94%) were subsequently submitted to a completion thyroidectomy. No statistically significant difference was found in terms of complications comparing both the TT Group with the HT + CT Group and the HT Group with the CT Group. The risk of complications in patients undergoing a completion thyroidectomy after a hemithyroidectomy for a thyroid nodule with an indeterminate cytology was comparable to that of patients submitted to primary thyroid surgery (both a total thyroidectomy and hemithyroidectomy).

Differentiation of benign thyroid nodules from malignant thyroid nodules through miR-205-5p and thyroid-stimulating hormone receptor mRNA

PURPOSE

This study was designed to determine the value of miR-205-5p and thyroid-stimulating hormone receptor (TSHR) mRNA in differentiating benign thyroid nodules from malignant thyroid nodules.

METHODS

A total of 67 patients with malignant thyroid nodules admitted to our hospital from October 2016 to March 2018 were enrolled in the malignant group, and 71 patients with benign thyroid nodules were enrolled in the benign group. Another 56 healthy individuals, as determined by physical examination, were enrolled in the control group. Quantitative real-time polymerase chain reaction (qRT-PCR) was adopted to determine the relative expression of miR-205-5p and TSHR mRNA in serum, and receiver operating characteristic (ROC) curves were used to analyze the diagnostic value of miR-205-5p and TSHR mRNA in thyroid nodules and their benignancy or malignancy. The correlation of miR-205-5p and TSHR mRNA with clinical data of the patients with thyroid carcinoma was analyzed, and multivariate logistic regression was used to analyze risk factors for lymph node metastasis of thyroid carcinoma. In addition, Pearson's test was used to analyze the relationship between miR-205-5p and TSHR mRNA in serum of patients with thyroid carcinoma.

RESULTS

The malignant group showed significantly higher expression of miR-205-5p and TSHR mRNA than the benign group and control group (both p <0.001), and the benign group showed significantly higher expression of these than the control group (p <0.01). miR-205-5p expression was related to tumor size, TNM staging, lymph node metastasis, capsular infiltration, and BRAF mutation (p <0.05), and TSHR mRNA expression was related to lymph node metastasis, capsular infiltration, BRAF mutation, and RAS mutation (p <0.05). Gender, number of lesions, capsular infiltration, miR-205-5p, and TSHR mRNA were independent risk factors for lymph node metastasis of patients with thyroid carcinoma. Moreover, there was a positive correlation between miR-205-5p and TSHR mRNA in patients with thyroid carcinoma (r=0.735, p<0.001).

CONCLUSION

MiR-205-5p and TSHR mRNA may be potential diagnosis indexes of thyroid nodules, their benignancy, or malignancy, while the independent risk factors for patients with thyroid carcinoma include a large number of lesions, occurrence of capsular infiltration, and relatively high expression of miR-205-5p and TSHR mRNA.

Thyroidectomy with energy-based devices: surgical outcomes and complications-comparison between Harmonic Focus, LigaSure Small Jaw and Thunderbeat Open Fine Jaw

Background

Being the thyroid gland a highly vascularized organ, achieving a meticulous hemostasis is essential to avoid serious complications. Currently, energy-based devices are widely used in thyroid surgery. The aim of this study was to compare Harmonic Focus (HF), LigaSure Small Jaw (LSJ) and Thunderbeat Open Fine Jaw (TB) in terms of surgical outcomes and complications.

Methods

Patients undergoing thyroidectomy in our Unit between January 2012 and June 2018 were retrospectively analyzed. According to the type of energy-device used, patients were divided into three groups: Group A (HF), Group B (LSJ) and Group C (TB).

Results

A total of 1,165 patients were included in this study: 1,012 in Group A, 96 in Group B and 57 in Group C. Demographic data and histopathological findings were comparable between the three groups. About the postoperative stay and complications, no statistically significant difference was found. The mean operative time was 89.41±20.60 minutes in Group A, 85.57±15.91 minutes in Group B and 78.07±17.67 minutes in Group C (P<0.01). However, the post-hoc test for all pairwise comparisons showed a statistically significant difference only between Group A and Group C.

Conclusions

HF, LSJ and TB have proved to be safe and effective. The postoperative stay and complications were comparable between the three groups. Considering the limits of our investigation, further studies are needed to investigate the effect of TB on operative times.

Effect of prophylactic central neck dissection on the surgical outcomes in papillary thyroid cancer: experience in a single center

PURPOSE

Morbidity due to papillary thyroid carcinoma (PTC) is increased mostly due to lymph node (LN) metastases, which lead to reoperations and complications associated with these operations. The aim is to compare the outcomes of PTC having total thyroidectomy and prophylactic central lymph node dissection (TT + PCND) with patients having total thyroidectomy (TT) alone.

METHODS

This study is a retrospective cohort analysis of 358 PTC patients that were operated by a single surgeon in a single center. Data about the patients were extracted from the medical records.

RESULTS

Of the patient cohort, 258 patients had TT + PCND (42.5 ± 11.3 years) and 100 patients (41.2 ± 11.9 years) had only TT. Total number of LN extracted in the TT + PCND group was 8.1 ± 6.9. The mean number of metastatic LN were 2.2 ± 1.9. Percentage of patients that had RAI were less in the TT + PCND group compared to the TT group. Seven patients (2.7%) in the TT + PCND group and 19 (19.0%) in TT group had recurrent disease (p < 0.0001). Of the complications, only transient hypoparathyroidism was increased in TT + PCND group compared to TT group (26.7% vs 10%, p < 0.0001).

CONCLUSION

TT + PCND performed by an experienced surgeon seems to decrease the number of LN recurrences, and the need for reoperations.

Impact of the Italian Society of Anatomic Pathology and Diagnostic Cytology Classification of Thyroid Nodules in the Treatment of Indeterminate Follicular Lesions: Five-Year Results at a Single Center

PURPOSE

Aim of the study was to assess the impact of the Italian Society of Anatomic Pathology and Diagnostic Cytology (SIAPEC) classification of 2014, on the treatment of indeterminate thyroid lesions (TIR3).

METHODS

We retrospectively analyzed patients undergoing thyroid surgery for TIR3 lesions between 2013 and 2018, at the General Surgery Department of Trieste University Hospital. According to the SIAPEC classification, patients were divided into TIR3A and TIR3B groups. All patients treated before 2014 underwent surgical treatment, and surgical specimens were retrospectively classified after revision of fine-needle aspiration cytology. Starting 2014, TIR3A patients were treated only when symptomatic (i.e., coexistent bilateral thyroid goiter or growing TIR3A nodules), whereas TIR3B patients always received surgical treatment. Hemithyroidectomy (HT) was the procedure of choice. Total thyroidectomy (TT) was performed in case of concurrent bilateral goiter, autoimmune thyroid disease, and/or presence of BRAF and/or RAS mutation. Lastly, we analyzed the malignancy rate in the two groups.

RESULTS

29 TIR3A and 90 TIR3B patients were included in the study. HT was performed in 10 TIR3A patients and 37 TIR3B patients, respectively, with need for reoperation in 4 TIR3B (10.8%) patients due to histological findings of follicular thyroid carcinoma >1  cm. The malignancy rates were 17.2% in TIR3A and 31.1% in TIR3B, (p = 0.16). Predictability of malignancy was almost 89% in BRAF mutation and just 47% in RAS mutation.

CONCLUSIONS

The new SIAPEC classification in association with biomolecular markers has improved diagnostic accuracy, patient selection, and clinical management of TIR3 lesions.

Incidental thyroid carcinomas. A retrospective study

AIM

The aim of the present study is to report our series of incidental thyroid carcinomas in the last 15 years and their follow-up, discussing therapeutics indications and surgical choices.

PATIENTS AND METHODS

We have considered 1793 patients operated on Surgical Sciences Department of "Sapienza" University of Rome from January 1, 2001 to December 31, 2015. The study was conducted on 83 totally thyroidectomized patients with a real incidental thyroid carcinoma, by clinical, laboratory and instrumental controls. Whole-body scan was the most important test in postoperative evaluation.

RESULTS

In our series, the incidence of incidental carcinomas was 4.62%. Compared to the total number of cancer patients, the percentage is 21,9%. In 15.66% of cases there was multifocality and in 7.23% also bilaterality. Regarding the histological type, in all cases they were papillary carcinoma. The size of the neoplastic lesions ranged from a minimum of 3 to a maximum of 10 mm. Whole-body scan revealed lymph node metastasis in 57.69% of patients.

DISCUSSION

Comparing these data with our previous studies we have seen a significant increase in incidence of incidental thyroid carcinomas over the years. Our therapeutical choice is total thyroidectomy and complection thyroidectomy after lobectomy, because of a relevant percentage of multifocality and/or bilaterality of these tumors. Many Authors on the contrary prefer a more conservative approach invoking the good prognosis of these tumors. The 57.69% of lymph node metastasis at postoperative whole-body scan comfort us in our setting.

CONCLUSION

Incidental thyroid carcinomas are not uncommon. We consider only tumors until 1 cm in diameter. Multifocality and bilaterality are often present such as occult lymph node metastasis. Our therapeutical choice is total thyroidectomy in order to conduct a proper follow-up.

Identification and interaction analysis of key miRNAs in medullary thyroid carcinoma by bioinformatics analysis

Medullary thyroid carcinoma (MTC) is an endocrine tumor and comprises 5–10% of all primary thyroid malignancies. However, the biomechanical contribution to the development and progression of MTC remains unclear. In this study, To discover the key microRNAs (miRNAs or miRs) and their potential roles in the tumorigenesis of MTC, the microarray datasets GSE97070, GSE40807 and GSE27155 were analyzed. The datasets were downloaded from the Gene Expression Omnibus (GEO) database. The differentially expressed miRNAs (DEMs) and genes (DEGs) were accessed by R. Targets of DEMs and predicted using starBase, and functional and pathway enrichment analyses were performed using Metascape. A protein-protein interaction (PPI) network and an analysis of modules were constructed using NetworkAnalyst. Finally, a network was constructed to show the regulatory association between transcription factors (TFs), DEMs and downstream genes. A total of 5 DEMs were found both in GSE97070 and GSE40807, including 3 upregulated DEMs and 2 downregulated DEMs. The Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses from Metascape revealed that the target genes of upregulated DEMs were significantly enriched in adherens junction, kinase and protein binding, while the target genes of downregulated DEMs were mainly involved in non-canonical Wnt signaling pathway and RNA transport. From the PPI network, 13 nodes were screened as hub genes. Pathway enrichment analysis revealed that the top 5 modules were mostly enriched in the neurotrophin signaling pathway, mRNA surveillance pathway and MAPK signaling pathway. In addition, the TF-DEMs-target gene and DEGs regulatory network revealed that 17 TFs regulated 2 miRNAs, including upregulated or downregulated DEMs, CREB1 regulated all upregulated DEMs, and TGFB1 was an activator of hsa-miR-199a-3p and a repressor of hsa-miR-429. Taken together, the present study identified several miRNAs and potential biological mechanisms involved in the tumorigenesis of MTC. This study identified the key DEMs and potential mechanisms underlying the development of MTC, and provided a series of biomarkers and targets for the management of MTC.

Correlation between iPTH Levels on the First Postoperative Day After Total Thyroidectomy and Permanent Hypoparathyroidism: Our Experience

Permanent hypoparathyroidism is the most common long-term complication after thyroidectomy. We evaluated whether iPTH concentrations on the first postoperative day may be a good predictor of this complication.

Patients undergoing thyroidectomy in our Unit between January 2017 and February 2018 who developed postsurgical hypoparathyroidism were analysed. According to iPTH values on the first postoperative day and on the basis of the detection threshold of the iPTH test used, patients were divided into 2 groups: Group A (iPTH < 6.3 pg/mL, undetectable), Group B (iPTH ≥ 6.3 pg/mL).

Seventy-five patients were included in this study: 64 in Group A and 11 in Group B. Permanent hypoparathyroidism occurred in 14 (21.88%) patients in Group A, while none developed this complication in Group B. When iPTH was < 6.3 pg/mL, the sensitivity for the prediction of permanent hypoparathyroidism was 100%, the specificity was 18.03%, the positive predictive value was 21.88% and the negative predictive value was 100%.

No patient with iPTH ≥ 6.3 pg/mL on the first postoperative day developed permanent hypoparathyroidism. On the other hand, iPTH concentrations < 6.3 pg/mL have not proved to be a strong predictor of this condition. However, this cut-off value can be useful to identify patients at risk of developing this complication.

The role of prophylactic central compartment lymph node dissection in elderly patients with differentiated thyroid cancer: a multicentric study

BACKGROUND

Prophylactic central neck lymph-nodes dissection is still a topic of major debate in Literature. There is a lack of randomized controlled trials proving advantages in its application in terms of overall survival and local recurrence. Due to the recent rapid increase of elderly population, differentiated tumor carcinoma diagnosis increased in patients over 65 years old. The aim of this study was to compare recurrence rate, complications rate and histological features of tumors in elderly population.

METHODS

A retrospective study was carried out collecting data from 371 patients with differentiated thyroid cancer without clinical evidence of lymph-nodes involvement in three Italian referral centers from 2005 to 2015. All patients were aged ≥ 65 years and were divided in two groups based on the performed surgery (total thyroidectomy alone or associated with central lymph-nodes dissection). Moreover, patients were stratified according to the age between 65 and 74 years old and over 75 years old.

RESULTS

Total thyroidectomy alone was performed in 184 patients (group A) and total thyroidectomy with prophylactic central neck dissection was performed in 187 cases (group B). There was a statistically significant difference in complications between the groups in terms of neck hematoma (0.5% group A vs 3.7% group B), temporary hypoparathyroidism (11.4% group A vs 21.4% group B), and temporary unilateral recurrent nerve injury (1.5% group A vs 6.4% group B). Lymph nodes recurrence rate was 9.2% in group A and 8.5% in group B, with no statistically significant difference. There was a statistically significant difference in patients over 75 years old in terms of temporary hypoparathyroidism (24% group A vs 11% group B), permanent hypoparathyroidism (2,7% group A vs 0,3% group B) and recurrent nerve injury (9,5% group A vs 2% group B).

CONCLUSIONS

The role of prophylactic central neck dissection is still controversial, especially in elderly patients, and an aggressive surgical approach should be carefully evaluated. The Authors reported a similar low recurrence rate between total thyroidectomy and total thyroidectomy associated with prophylactic central neck dissection, with increased postoperative complications in the lymphadenectomy group and in patients over 75 years old, advocating a tailored surgical approach in elderly population.

Thyroiditis process as a predictive factor of sternotomy in the treatment of cervico-mediastinal goiter

Background

About 10% of cervico-mediastinal goiter need to associate cervicotomy with a total or partial sternotomy to allow a safe removal of the goiter.

Aim of this study is to identify preoperative predictors of sternotomy for mediastinal goiter.

Methods

Between January 2008 and December 2015, 586 patients were submitted to total thyroidectomy at Surgical Clinic of Brescia, Italy.

Among these, patients with cervico-mediastinal goiter have been divided in two groups based on the necessity of an associated sternotomy in the operating field: Group 1 (n = 40 patients) did not need sternotomy and Group 2 (n = 4 patients) underwent cervicotomy associated with sternotomy.

Clinical and pathological characteristics of patients were retrospectivelly recorded.

Results

Among study group, 44 patients had cervico-mediastinal goiter. Thoracic CT was performed in all patients: an extension above aortic arch was found in 41 patients (93.18%) while an extention below aortic arch was found in 3 patients (6.82%).

The extension of the goiter below the aortic arch resulted as a predictive value in the choice of surgical treatment (p = 0.0001).

The thyroiditis process was found to be a significant predictive of the extention to a sternotomic approach (p = 0.029).

The years of goiter’s presence were on average 8.40 years in Group 1 and 14.75 years in Group 2.

These parameters proved to be predictive when choosing a cervicotomy with sternotomy.

Conclusions: Our study, despite limitations posed by small sample and its retrospective analisys, highlights the role of goiter’s extention (below the aortic arch), disease length (for more than 14.75 years) and flogistic process (positivity of Tg Ab and anti-TPO-Ab) in the choice of combined (cervicotomic and sternotomic) approach to goiter’s removal.

Follicular proliferation TIR3B: the role of total thyroidectomy vs lobectomy

BACKGROUND

TIR3B thyroid nodules are considered to be at risk of malignancy (15-30%) but guidelines recommend conservative surgery with lobectomy with primary diagnostic porpoise. Risk stratification mainly based on ultrasound, elastography and genetic mutations usually may influences the surgical approach.

METHODS

We retrospectively analyzed 52 cases of TIR3B underwent between 2015 and 2017 total thyroidectomy (TT) and lobectomy (L), focusing mainly on the observed rate of malignancy. Chi-squared test and Fisher's exact probability test were used for analysis, considering a P values less than 0.05 as significant.

RESULTS

Out of 52 patients 49 underwent TT and 3 L. In TT group a multinodular goiter was associated in 67.3% of patients. Malignancy rate was 81.6 and 33.3% respectively after TT and L (P 0.003). Multicentric and contralateral tumors were detected respectively in 36.7% and in 32.6% of patients underwent TT. No main post-operative complications were registered.

CONCLUSIONS

Ultrasound and elastography are useful to define within the TIR3B group those lesions at higher risk and therefore requiring a more radical approach. TT seems an appropriate approach to TIR3B lesions, especially in multinodular goiter, considering the incidence of malignancy with probably higher rate than previously reported.

Thyroid disease and cancer in kidney transplantation: a single-center analysis

BACKGROUND

Thyroid diseases are frequent in patients with end-stage renal disease, but data on renal transplant recipients are conflicting. This study evaluated the incidence of thyroid disease and cancer in a population of kidney transplant recipients performed in a single center.

METHODS

Seven hundred sixty patients receiving a kidney transplantation between January 2000 and October 2017 were followed with thyroid ultrasonography to determine nodules together with thyroid hormone levels. Ultrasound-guided fine-needle aspiration citology (FNAc) was performed to the nodules > 10 mm .

RESULTS

Two hundred four patients (26.8%) patients demonstrated functional or morphologic changes in the thyroid gland compared with pre-transplant period. Among the 204 patients with newly diagnosed thyroid disease, 165 patients had single or multiple nodular lesions less than 1 cm in diameter, and were followed yearly. Nodule size progression was observed in 23 patients (13.9%), and they underwent a FNAc. A total of sixty-two patients (30.3%) underwent FNAc. The biopsy samples were cytologically interpreted as benign in 20 patients (32.2%), suspicious in 40 patients (64.5%), or at high risk of cancer in 2 patients (3.2%). Forty-two patients underwent total thyroidectomy. At histological examination, 18 patients had a thyroid cancer (papillary cancer in 17 patients, follicular cancer in one). Thyroid cancer was more frequent in male patients with a mean time from transplant to diagnosis of 5.6 years. At a mean follow-up was 8 ± 1.2 years, all patients are alive with a normal functioning graft.

CONCLUSIONS

Thyroid diseases are common in transplant recipients. Thyroid disease may evolve after transplantation, probably as a consequence of immunosuppression. A complete evaluation of thyroid disease is mandatory in kidney transplant recipients because early diagnosis and appropriate treatment of thyroid disease and cancer may significantly decrease the morbidity and mortality in these patients.

How to handle borderline/precursor thyroid tumors in management of patients with thyroid nodules

Thyroid carcinomas originating from follicular cells have the prognosis of heterogeneous diseases, but pathologists classify them all as malignant disease. Epidemiologists have issued a stern warning regarding over-diagnosis and overtreatment of patients with indolent thyroid tumors that cause no harm to the patients. Review of the literature revealed that there were several proposals of borderline/precursor tumors to some indolent thyroid carcinomas. Thyroid tumor of uncertain malignant potential (UMP) was first proposed by Williams for encapsulated follicular pattern thyroid tumors to solve problems due to observer variation. Rosai et al. proposed to rename papillary microcarcinoma (PMC) to papillary micro-tumor as the overwhelming majority of them are of no clinical significance. Liu et al. proposed well-differentiated tumor with uncertain behavior (WDT-UB) which covered WDT of UMP (WDT-UMP) and non-invasive encapsulated follicular variant of papillary thyroid carcinoma (EFVPTC). The EFVPTC without invasion was renamed as non-invasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP) by an international panel of pathologists. A new prognostic classification of thyroid tumors was proposed by Kakudo et al., in which extremely low risk tumors were grouped in a borderline tumors category. The borderline/precursor thyroid tumors included encapsulated tumors [capsular invasion only follicular carcinoma, encapsulated papillary carcinoma without invasion, WDT-UMP and follicular tumor of UMP (FT-UMP)] and non-encapsulated tumors (PMC). The UMP and NIFTP were incorporated in the 4th edition WHO classification of thyroid tumors as a new tumor entity in chapter 2-2A: other encapsulated follicular patterned thyroid tumors. Their behavior codes were decided to be 1 (borderline or uncertain behavior), and not 0 (benign), 2 (in situ carcinoma) or 3 (malignant). These borderline/precursor thyroid tumors are indolent tumors biologically and should be treated more conservatively than as previously recommended for thyroid follicular cell carcinomas [total thyroidectomy (TTX) followed by radio-active iodine (RAI) treatment] by western clinical guidelines.

Prevalence of hypothyroidism among patients with isthmus-preserved thyroid lobectomy

Objective

To investigate the prevalence of hypothyroidism following thyroid lobectomy with isthmus preservation.

Methods

This retrospective, case series study included patients who had undergone thyroid lobectomy with preserved isthmus that was reversed onto the contralateral lobe. Neck ultrasound was performed in all patients and the patients were followed for 2 years.

Results

Out of 170 patients enrolled into the study, three were excluded due to preoperative hypothyroidism and one due to isthmusectomy; of the remaining 166 included in the final analyses, 139 patients (83.7%) were female, 27 (16.3%) were male, and patient age ranged between 17 and 77 years. The indication for intervention was thyroid swelling in 141 patients (84.9%). Final diagnoses following histopathological examination comprised benign lesion in 145 cases (87.3%), malignancy (follicular carcinoma and papillary thyroid carcinoma) in 12 cases (7.2%) and thyroiditis in nine cases (5.4%). During the 2-year post-surgery follow-up, 165 patients (99.4%) were euthyroid and one patient (0.6%) developed hypothyroidism.

Conclusion

Postoperative hypothyroidism following thyroid lobectomy appears to be very rare when the isthmus is preserved and reversed onto the contralateral lobe.

Factors predicting hypocalcemia after total thyroidectomy - A retrospective cohort analysis

BACKGROUND

Hypocalcemia after total thyroidectomy is the most frequent complication resulting in prolongation of hospitalisation. Therefore we aimed to analyse clinical risk factors predictive for hypocalcemia and its long term persistence after total thyroidectomy.

METHODS

Retrospective analysis of patients undergoing total thyroidectomy from 2005 until 2013. Outcome measures were initial postoperative hypocalcemia defined as serum calcium below 2.0 mmol/l after total thyroidectomy within 48 h and persistent hypocalcemia defined as serum calcium below 2.0 mmol/l above six months and/or the need for additional calcium and vitamin D supplementation.

RESULTS

Initial postoperative hypocalcemia was present in 160 of 702 patients (22.8%) with 91 patients (13%) developing symptoms. 48 patients (6.8%) had a persistent hypocalcemia above six months. Patients with an initial symptomatic postoperative hypocalcemia showed significantly more often a persistent hypocalcemia compared to asymptomatic patients with biochemical hypocalcemia (38 patients (41.8%) vs. 10 patients (14.5%), p < 0,001). In the binary logistic regression analysis, female gender (OR 2.4; CI95% 1.5-3.8), prolonged surgery time >189 min (OR 1.8; CI95% 1.2-2.6) and parathyroid reimplantation (OR 2.4; CI95% 1.2-4.7) were associated with initial hypocalcemia while only initial symptomatic hypocalcaemia was shown to be independently associated with persistent hypocalcemia (OR 40.9; CI95% 18.5-90.4).

CONCLUSION

Prolonged surgery time seems to correlate with initial postoperative hypocalcemia independently of the underlying disease and surgical expertise but does not affect the persistence of hypocalcemia. Initial symptomatic postoperative hypocalcemia after total thyroidectomy is associated with a high rate of persistent hypocalcemia.

A favorable tumor size to define papillary thyroid microcarcinoma: an analysis of 1176 consecutive cases

Background

The optimal treatment strategy for papillary thyroid microcarcinoma (PTMC) has remained controversial. The purpose of this study was to provide a new reference value for PTMC to aid the selection of optimal management for minute lesions.

Patients and methods

A pool of 1176 consecutive patients who met the inclusion criteria were ultimately enrolled in this study. The correlation of papillary thyroid carcinoma (PTC) tumor size and lymph node metastasis was analyzed. Receiver operating characteristic curve studies were conducted to identify the reference value by determining the optimal cut-off point of size related to lymph node metastasis. To validate our results, all selected patients were divided into two groups according to the cut-off point and some of the prognostic factors were compared.

Results

A moderate significant correlation was found between the tumor size and the average number of lymph node metastases (r=0.502, P<0.01) and the percentage of lymph node metastasis (r=0.625, P<0.01). The optimal cut-off reference value was 8.5 mm according to the receiver operating characteristic curves. Significant differences were observed for PTC prognostic factors, for example, extrathyroidal extension, multifocality, pathologic (p) N+ stage, occult metastasis in clinical (c) N− stage, radioactive iodine ablation, and recurrence between the two groups.

Conclusion

Due to more aggressive behavior and poorer prognosis in larger tumor size (>8.5 mm), a tumor size ≤8.5 mm in diameter may be favorable to discriminate PTMC from PTC and aid the selection of optimal management.

Clinical behaviors of rare variants of papillary thyroid carcinoma are associated with survival: a population-level analysis

Objective

This study was to evaluate the risk factors of survival in patients with columnar cell variant (CCV) and encapsulated variant (ECV).

Materials and methods

The Surveillance, Epidemiology, and End Results database (1988–2013) was used to compare the characteristics of CCV and ECV with those of classic papillary thyroid carcinoma (PTC). Survival was analyzed by the Kaplan–Meier method, the log-rank test, and Cox multivariate regression. Multivariate logistic regression was used to further analyze lymph node metastases and distant metastasis. There were 765 CCV, 529 ECV, and 39,035 PTC patients. ECV tumors were similar to PTC in terms of overall survival, disease-specific survival, age, sex, and distant metastasis.

Results

Compared with PTC, CCV tumors tended to be larger, with a higher incidence rate among males and in patients ≥65 years of age. CCV was associated with higher rates of extrathyroidal extension, multifocality, lymph node examinations, and lymph node and distant metastases (p<0.0001). Significant differences were found in 10-year overall survival (97.14% vs 89.15%, p<0.0001) and disease-specific survival (99.08% vs 93.07%, p<0.0001) between PTC and CCV. In CCV, distant metastasis (hazard ratio 5.125, p<0.0001) and lymph nodal metastasis (hazard ratio 2.152, p=0.032) predicted a poor prognosis. After adjustment, distant metastasis was independently associated with age ≥65 years, and lymph nodal metastasis was independently associated with female sex (odds ratio [OR] 0.341 [0.234–0.496]), extrathyroidal extension (OR 2.453 [1.368–4.397]), multifocality (OR 2.168 [1.318–3.569]), size >20 mm, ≤40 mm (OR 1.851 [1.170–2.928]), and size >40 mm (OR 1.847 [1.088–3.136]).

Conclusion

ECV appears to have a similar prognosis to PTC, while CCV has a worse prognosis than classic PTC. Treatment with external beam radiotherapy and radioactive implants should be conducted carefully in patients with CCV.

A clinical framework to facilitate selection of patients with differentiated thyroid cancer for active surveillance or less aggressive initial surgical management

INTRODUCTION

In the past, total thyroidectomy was usually recommended as the initial therapeutic approach in all but the lowest risk differentiated thyroid cancers. Today, many patients with low risk papillary thyroid cancers may be candidates for either an observational management approach (active surveillance/deferred surgical intervention) or a minimalist surgical approach (thyroid lobectomy/isthmusectomy).

AREAS COVERED

After a comprehensive review of the PubMed database and based on our clinical experience, we describe a clinical framework that integrates important factors in three major inter-related domains (pre-operative imaging/clinical findings, medical team characteristics, and patient characteristics) to classify a patient as either ideal, appropriate or inappropriate for conservative treatment options. As part of this clinical framework, we examine how the medical decision making construct (minimalist versus maximalist) of the patient and clinician can impact selection of initial therapy.

EXPERT COMMENTARY

The dramatic rise in the incidence of very low risk differentiated thyroid cancer demands a re-evaluation of the appropriate use of more minimalistic treatment options. The selection of appropriate patients for less aggressive initial treatment options requires thoughtful, open discussions that can be aided by clinical decision making frameworks that recognize and value the medical decision making process of clinicians and patients.

Does hyperthyroidism worsen prognosis of thyroid carcinoma? A retrospective analysis on 2820 consecutive thyroidectomies

Background

Hyperthyroidism is associated with high incidence of thyroid carcinoma; furthermore, tumors arisen in hyperthyroid tissue show an aggressive behavior. Thyroid Stimulating Hormone (TSH) and Thyroid-stimulating antibodies, present in Graves’s disease, seem to play a key role in carcinogenesis and tumoral growth.

Methods

We retrospectively reviewed our series of patients who underwent thyroidectomy for thyroid carcinoma. We compared pathological features and surgical outcomes of hyperthyroid versus euthyroid patients.

Results

From 2007 to 2015, 909 thyroidectomies were performed at our institution for thyroid cancer: 87 patients were hyperthyroid and 822 euthyroid. We observed, in hyperthyroid patients, a higher rate of transient hypoparathyroidism (28.1% vs 13.2%; p < 0.01) and of node metastases (12.6% vs 6.1%; p = 0.03); also local recurrence rate was higher (5.7% vs 2.5%) even if not statistically significant (p = 0.17). Five-year disease free survival rate was significant lower in the same group (89.1% vs 96.6%; p = 0.03).

Conclusion

Thyroid cancers in hyperthyroid patients have an aggressive behavior, with high incidence of local invasion and a worse prognosis than euthyroid patients. All hyperthyroid patients should undergo a careful evaluation with ultrasound and scintigraphy; in case of suspicious nodules, an aggressive approach, including thyroidectomy and lymphectomy, is justified. In patients with toxic adenoma, thyroid cancer is uncommon, thus a loboisthmectomy can be safely performed.

Trial registration number

Research registry n. 2670 registered 19 June 2017 (retrospectively registered).

Multifocality as a prognostic factor in thyroid cancer: A meta-analysis

BACKGROUND

Thyroid cancer is one of the most common endocrine cancers whose incidence has been steadily increasing. Previous studies have suggested that multifocality in thyroid cancer is associated with poor prognosis. The present study aims to quantify the data on multifocality as a factor indicating poor prognosis by meta-analysis.

METHODS

A systematic search was carried out using the electronic databases PubMed and Medline. We searched for articles containing keywords of multifocality and thyroid cancer, as well as risk factors and prognostic factors for thyroid cancer (Lymph node metastases, extrathyroidal extension, distant metastases, disease recurrence, Age, tumour size. and gender). Data sets containing hazard ratios and odds ratios were then compared.

RESULTS

The meta-analysis was performed using a total of 21 articles, showed that multifocality is associated with an increased risk of development of LNM (12 Studies: OR = 1.87; 95% CI = 1.51-2.32; I2 = 49.11; p-value = .03), Extrathyroidal extension (15 Studies: OR = 3.18; 95% CI = 0.69-14.71; I2 = 95.62; p-value <.001), Tumour Size > 1 cm (3 Studies: OR = 2.75; 95% CI = 1.95-3.89; I2 = 0.00 and p-value = .88) and disease recurrence (5 Studies: HR = 2.81; 95% CI = 1.07-7.36; I2 = 95.85; p-value < .001). Risk factors that did not significantly contribute to a higher incidence of multifocality include Age >45, Male Gender.

CONCLUSIONS

Multifocality in thyroid cancer is a significant risk factor for disease progression and increases the risk of disease recurrence. The present study suggests that patients who have multifocal disease should therefore be managed more aggressively from an operative and post-operative perspective.

Rationality in prophylactic central neck dissection in clinically node-negative (cN0) papillary thyroid carcinoma: Is there anything more to say? A decade experience in a single-center

AIM

Papillary thyroid carcinoma (PTC) is the most common thyroid malignancy. Despite its extremely favorable prognosis, cervical lymph node metastases are a common feature of PTC and a known independent risk factor for local recurrence. However, the role of prophylactic central neck dissection (PCND) remains a matter of debate in patients with clinically node-negative (cN0) PTC. To better clarify the current role of PCND in the surgical treatment of PTC, evaluating advantages and disadvantages of PCND and outcome of cN0 PTC patients who have been treated with either total thyroidectomy alone or in combination with PCND. A review of recent literature data is performed.

METHODS

Between January 2000 and December 2015, 186 consecutive patients with cN0 PTC were identified to be included in the present study. 74 of these underwent total thyroidectomy associated with PCND, while 112 patients underwent total thyroidectomy alone. The epidemiological and clinical-pathological data of all patients included were collected at diagnosis and during follow-up.

RESULTS

Overall complication rate was significantly higher in the group of patients undergoing PCND (39.2% vs. 17.8%, p = 0.0006). To be specific, they presented a considerably increased risk of temporary recurrent laryngeal nerve injury (p = 0.009) and of permanent hypothyroidism (p = 0.016). Overall survival and recurrence rates did not differ between those undergoing PCND and those undergoing total thyroidectomy alone (p = 1.000 and p = 0.715, respectively).

CONCLUSIONS

The results of the present study do not support the routine use of PCND in the treatment of cN0 PTC patients.

Unintentional recurrent laryngeal nerve injuries following thyroidectomy: Is it the surgeon who pays the bill?

BACKGROUND

Thyroidectomy is one of the most common intervention in general surgery and, after the turn of the century, its rate has sharply increased, along with a worldwide increased incidence of differentiated thyroid cancers. Therefore, injuries of the recurrent laryngeal nerve have become one of the most frequent cause of surgical malpractice claims, mostly following surgery for benign pathology.

MAIN BODY

Even if the incidence of definitive paralysis is generally lower than 3%, during the last 20 years in Italy, the number of claims for damages has sharply raised. As a consequence, a lot of defensive medicine has been caused by this issue, and a witch-hunt has been accordingly triggered, so determining mostly a painful and lasting frustration for the surgeons, who sometimes are compelled to pay a lot of money for increasing insurance premiums and lawyers fees. Recurrent laryngeal nerve injury should be considered as a potentially catastrophic predictable but not preventable event, rather than the result of a surgical mistake.

CONCLUSION

Purposes of the Authors are analyzing incidence, conditions of risk, and mechanisms of recurrent laryngeal nerve injuries, underlining notes of surgical technique and defining medical practice recommendations useful to reduce the risk of malpractice lawsuits and judgments against surgeons.

Partial thyroidectomy for papillary thyroid microcarcinoma: Is completion total thyroidectomy indicated?

AIM

Papillary thyroid microcarcinoma (PTMC) is increasing in incidence. Despite its excellent clinical outcomes, there is still debate regarding which surgical approach is more appropriate for PTMC, procedures including hemithyroidectomy (HT), total thyroidectomy (TT), and completion thyroidectomy (CT) after initial HT and histopathologic examination confirming a PTMC. Here we report our experience in the surgical management of PTMC.

METHODS

We conducted a retrospective evaluation of all patients who received a postoperative diagnosis of PTMC between January 2001 and January 2016. Every patient was divided according to the type of surgery performed (TT or HT alone). Follow-up consisted of regular clinical and neck ultrasonographic examination. Clinical and histopathological parameters (e.g. age, sex, lesion size, histological features, multifocality, lymph node metastases, BRAF status when available) as well as clinical outcomes (e.g. complications rates, recurrence, overall survival) were analyzed.

RESULTS

Group A consisted of 86 patients who underwent TT, whereas Group encompassed 19 patients who underwent HT. Mean follow-up period was 58.5 months. In Group A, one patient (1.2%) experienced recurrence in cervical lymph nodes with need for reoperation. In Group B, eight patients (42%) underwent completion thyroidectomy after histopathological examination confirming PTMC, while one patient (5.3%) developed PTMC in the contralateral lobe with need for reoperation at 2 years after initial surgery. Multifocality was found in 19 patients in Group A (22%). Of these, 14 presented bilobar involvement, whereas in 3 cases multifocality involved only one lobe. 1 patient in Group B (5.3%) presented with unilateral multifocal PTMC (p = 0.11).

CONCLUSIONS

Low-risk patients with PTMC may benefit from a more conservative treatment, e.g. HT followed by close follow-up. However, appropriate selection of patients based on risk stratification is the key to differentiate therapy options and gain better results.

Cost-effectiveness analysis in papillary thyroid carcinoma patients with different neck dissection strategy: A retrospective cohort study

BACKGROUND

There are two surgical strategies for bilateral neck dissection (BND), simultaneous and two-stage operations. The aim of the study was to compare the cost-effectiveness BND with this two operations in papillary thyroid carcinoma (PTC) patients.

MATERIALS AND METHODS

Consecutive PTC patients undergoing BND were studied retrospectively, and were classified into simultaneous group (Group A) and two-stage group (Group B). Demographic, medical costs, complication and surgical variables were recorded.

RESULTS

This study included 256 PTC patients, of which 175 (68.4%) underwent simultaneous BND and 81 (31.6%) patients underwent two-stage. Patients in Group B spent almost twice as much on medical costs as patients in Group A ($4145.3 vs. $7352.5). Group A patients also had shorter hospital stays (11.71 ± 5.12 vs. 23.10 ± 7.11, P < .0001) and surgery times (203.61 ± 61.43min vs. 279.58 ± 71.59min, P < .0001). The average radioactive iodine therapy delay was 67 days in Group B. There was no significant difference in complications (34 vs. 18, P = .605) or disease-free-survival (93.71% vs. 90.12%, P = .243) between the two groups. No difference was found in rates of recurrent laryngeal nerve invasion/resection (12 vs. 11, P = .08; 10 vs. 6, P = .353) or tracheotomy (32 vs. 14, P = .846). However, internal jugular vein invasions were more common in patients with two-stage BND (7 vs. 9, P = .029).

CONCLUSION

Simultaneous BND is the most cost-effective strategy for the management of PTC patients without bilateral internal jugular veins invasion, due to lower treatment cost and the ability to avoid RAI delay.

Thyroid reoperation using intraoperative neuromonitoring

PURPOSE

Thyroid reoperations are at a high risk of recurrent laryngeal nerve (RLN) injury. The aim of the study was to investigate whether the use of intraoperative neuromonitoring (IONM) can aid in the RLN identification and minimize the risk of its injury, in comparison with visual RLN identification.

METHODS

This was a retrospective cohort study of patients who underwent thyroid reoperations with and without the use of IONM. Primary endpoint was the RLN identification rate; secondary: the prevalence of RLN injury, the frequency of total thyroidectomies, and the course of the RLN.

RESULTS

The study involved 61 patients undergoing thyroid reoperation among whom 24 were operated on with visual RLN identification only, while 37 procedures used IONM. In the non-monitored reoperations, 44.4% of the RLN were visually identified, as opposed to 91.6% in the IONM group (p < 0.001). Transient paresis occurred in three nerves with visualization (6.6%), and in one in IONM group 1.6% (p = 0.185). Permanent paresis occurred in the group with visualization (6.6%), as opposed to none with neuromonitoring. The extent of resection in both groups was significantly different (p = 0.043). Total, near-total thyroidectomies, Dunhill operations and subtotal thyroidectomies were performed in 71, 17, 4, and 8% in the visualization group, and in 94, 0, 3, and 3%, respectively, in the IONM group. A non-anatomical RLN course was observed in 80% of the reoperations with IONM.

CONCLUSIONS

Thyroid reoperation should be performed using IONM, because it allows for a significantly improved RLN identification rate and a significantly more radical resection.

The futility of intraoperative frozen section in the evaluation of follicular thyroid lesions

OBJECTIVE

Investigate the utility of intraoperative frozen section (iFS) in patients with follicular thyroid lesions following publication of the 2015 American Thyroid Association (ATA) guidelines.

STUDY DESIGN

Retrospective chart review.

METHODS

Patient demographics, preoperative cytology, frozen pathology, and final pathology were reviewed on patients undergoing thyroid surgery at a tertiary care hospital in which iFS was utilized over a 5-year period. The test performance of iFS and the frequency of indicated completion/total thyroidectomies pre- and postpublication of the 2015 ATA guidelines were calculated.

RESULTS

One hundred and one patients met inclusion criteria: 54 patients with follicular lesions of undetermined significance (FLUS) and 47 patients with a cytologic diagnosis of suspicious for follicular neoplasm/follicular neoplasm. The malignancy rate was 36%, but only 14% of malignancies were identified on iFS. A definitive benign or malignant diagnosis was given on iFS in only 21% of cases, and operative management was altered in two cases as a result of iFS. There was a statistically significant reduction in the frequency of indicated total/completion thyroidectomies based on high-risk features as a result of the 2015 ATA guidelines compared to prior recommendations (20.8% vs. 5.0%, P = < 0.001). None of these patients had findings on iFS that would have altered management intraoperatively.

CONCLUSION

Intraoperative frozen section offers minimal diagnostic utility in the evaluation of follicular thyroid lesions. Updates in the 2015 ATA guidelines further diminish its potential to impact management intraoperatively. Significant improvements in its ability to identify malignancies would be needed to justify its use.

LEVEL OF EVIDENCE

4. Laryngoscope, 128:1501-1505, 2018.

Intraoperative measurement of thyroglobulin in lymph node aspirates for the detection of metastatic papillary thyroid carcinoma

Background

Among patients with papillary thyroid carcinoma (PTC), 30%–80% have cervical lymph node (LN) metastases, which are most commonly located in the central compartment. However, preoperative ultrasonography identifies malignant central compartment LNs in only 20%–30% of cases. We aimed to evaluate the diagnostic value of intraoperative thyroglobulin (Tg) measurement in fine-needle aspirates (FNA-Tg) of suspicious metastatic LNs.

Methods

In total, 75 patients (75 LNs) with PTC or suspected PTC were enrolled in this study. Suspicious metastatic LNs were isolated intraoperatively, and FNA-Tg was performed. Then, the Tg values were compared with the corresponding pathological results and preoperative ultrasonography.

Results

In total, 37 LNs were diagnosed as malignant, and 38 were benign. According to the receiver operating characteristic (ROC) curve, the optimal cutoff value of intraoperative FNA-Tg was 147.5 ng/mL (sensitivity, 81.1%; specificity, 100%; p=0.000). The sensitivity and specificity for detecting central compartment LN metastasis were 77.78% (21/27) and 100% (36/36), respectively. The corresponding sensitivity of preoperative ultrasonography was lower than that of FNA-Tg (p=0.000). Serum Tg-antibody (Ab), thyroid-stimulating hormone (TSH) and thyroid peroxidase antibody (TPO-Ab) were not significantly associated with FNA-Tg values. There was no statistical correlation between preoperative serum Tg and intraoperative FNA-Tg (p=0.451).

Conclusion

Intraoperative FNA-Tg levels of suspicious metastatic cervical LNs can be useful for diagnosing metastatic PTC. Intraoperative LN-FNA-Tg may have an important role in determining which surgical procedure to perform.

Predictive factors and prognosis for recurrent laryngeal nerve invasion in papillary thyroid carcinoma

Background

Recurrent laryngeal nerve (RLN) invasion in papillary thyroid carcinoma (PTC) is one of the main predictors of poor prognosis. The present study investigated the risk factors for RLN invasion in PTC patients.

Methods

A total of 3,236 patients who received thyroidectomy due to PTC in Thyroid and Parathyroid Surgery Center of West China Hospital of Sichuan University were reviewed. Demographics and clinical factors, imaging examination (ultrasonography) characteristics, surgical details, postoperative pathological details, recurrence, and postoperative complications were recorded. Univariate and multivariate analyses were used to study the risk factors of RLN invasion, Kaplan–Meier method was performed to compare the outcomes of tumor recurrence.

Results

Patients with RLN invasion had a higher recurrence rate than those in the control group (p<0.001). Multivariate analyses showed that age greater than 45 years (p<0.001), a largest tumor size bigger than 10 mm (p<0.001), clinical lymph node metastasis (cN1) (p<0.001), posterior focus (p<0.001), extrathyroidal extension (p<0.001), esophageal extension (p<0.001), tracheal extension (p<0.001), and preoperative vocal cord paralysis (p<0.001) were independent predictors for RLN invasion.

Conclusion

PTC patients with RLN invasion have a negative prognosis and a higher recurrence rate. Meticulous operation and careful follow-up of patients with the above factors is recommended.

Early discharge after total thyroidectomy: a retrospective feasibility study

AIM

The continued hospitalization after total thyroidectomy is often due to the onset of hypocalcemic complications more than 24 hours after surgery. So it would be important to predict which patients will not develop the hypocalcemic complication to discharge them early. This was the aim of our study.

PATIENTS AND METHODS

Our retrospective study was conducted on 327 consecutive thyroidectomized patients, operated on for benign and malignant diseases. We evaluated the values of preoperative serum calcium levels (Cal0) and of the first postoperative day (Cal1) and two new variables were calculated (dCal and dCaln). The same thing was made on a subgroup of 111 patients in whom also parathiroyd hormone (PTH) values were detected. Statistical analysis was performed with the goal of determining if we could establish a safe criterion for discharge at 24 hours after surgery and if there is a correlation between suitability for discharge and diagnosis.

RESULTS

As to discharge, the predictive power of the discriminant function applied was significant both on the total of patients and in the subgroup of 111 patients, but it was clinically unacceptable because it would expose us to a 21% to 27% error rate. It is not possible to identify a threshold, below which to consider patients surely dischargeable. The diagnosis does not appear correlated with the suitability for discharge.

CONCLUSION

On the basis of serum calcium and PTH levels in the first postoperative day, it is impossible to predict which patients can be discharged 24 hours after surgery without incurring in hypocalcemic complications.