Clinical Study of Ultrasonographic Risk Factors for Central Lymph Node Metastasis of Papillary Thyroid Carcinoma

BackgroundThyroid cancer is the most common malignancy of the endocrine system worldwide. Papillary thyroid cancer (PTC) is the most common pathologic type. The preoperative diagnosis of PTC and central lymph node metastasis (CLNM) or metastatic tendency is of great clinical significance to the diagnosis, treatment and prognosis of these patients. This study was conducted to investigate the correlation between ultrasound features and central CLNM of PTC.MethodsThis study retrospectively analyzed patients who underwent PTC surgery and central lymph node dissection in the Department of Surgery, Beijing Tiantan Hospital, from January 2019 to February 2020. According to the inclusion and exclusion criteria, data from 136 patients were ultimately included, and the clinical and ultrasonic data of the patients were analyzed by multivariate regression to evaluate the correlation among grayscale ultrasound (US), superb microvascular imaging (SMI) and contrast-enhanced ultrasound (CEUS) features of thyroid nodules and CLNM of PTCs.ResultsThe multivariate analysis showed that tumor size, multifocality, microcalcification characteristics, SMI vascularization, and CEUS evaluation of contact with the adjacent capsule were correlated with PTC metastasis (P=0.008, P=0.001, P=0.028, P=0.041, and P< 0.001, respectively). Comparisons of the area under the ROC curves revealed that the area under the ROC curve of the degree of nodular invasion into the thyroid capsule was the largest (AUC: 0.754). The sensitivity and specificity for evaluating CLNM of PTC were 67.7% and 83.1%, respectively.ConclusionsUltrasound characteristics of the following features are associated with a high risk of lymph node metastasis in PTCs: maximum diameter of nodules ≥1 cm, multifocality, ≥5 microcalcifications, abundant blood flow of SMI in nodules and nodule contact with the thyroid capsule ≥25% under CEUS. Ultrasound has clinical value in the preoperative evaluation of CLNM of PTCs.

Continuous, Large-Volume Hydrodissection to Protect Delicate Structures around the Thyroid throughout the Radiofrequency Ablation Procedure

<b><i>Introduction:</i></b> Small-volume hydrodissection liquid dissipates rapidly and confers only short-term protection during radiofrequency ablation (RFA) of benign thyroid nodules. The aim of this study was to establish a safe method for continuous, large-volume hydrodissection. <b><i>Methods:</i></b> A long needle was inserted and positioned outside the thyroid capsule; 5% glucose was injected to maintain a 3- to 5-mm continuous safety buffer. From October 2015 to July 2020, 166 patients underwent hydrodissection with different volumes, and ablation efficacy and complications associated with different liquid volumes (≤40 mL vs. &#x3e;40 mL) were compared at 1-month postprocedure. Moreover, 20 mL liquid (equivalent to 250 mL in the human body) was injected around the thyroid of a rhesus monkey, after which CT scans were used to visualize the liquid’s fate and verify its safety. <b><i>Results:</i></b> The 51 patients with 10–40 mL injections and 116 patients with larger injections (45–450 mL) showed similar complete ablation rates (88.46% vs. 90.44%, <i>p</i> = 0.582), comparable 6-month VRR (82.79% vs. 76.62%, <i>p</i> = 0.079), and complication incidences, although the latter group had larger nodules (9.11 mL vs. 13.79 mL, <i>p</i> = 0.003), more energy delivered (3.44 kcal vs. 6.04 kcal, <i>p</i> &#x3c; 0.001), and longer operation times (51.37 min vs. 69.2 min, <i>p</i> &#x3c; 0.001). In the animal experiment, the 20 mL of liquid diffused quickly (within 10 min) from the vicinity of the thyroid to the mediastinum and retropharyngeal space. It was observed in the kidneys at 10 min and disappeared from the neck and chest space by 24 h. <b><i>Conclusions:</i></b> Continuous, large-volume hydrodissection can protect the delicate structures around the thyroid throughout the RFA procedure and might be beneficial in large thyroid nodule ablation.

Papillary thyroid microcarcinoma: distinct form or cancer growth stage?

Background. Over the past decades an increase in the incidence of papillary thyroid microcarcinoma (PTMC) has been observed throughout the world owing to the improved diagnostics. There are many different opinions about the aggressiveness degree of this group of tumors, as well as about the tactics of managing patients with PTMC.Aim of the study is the identification of the prognostic factors responsible for the features of the clinical course, including the more aggressive one.Materials and methods. A study was carried out with a detailed analysis of a group of patients with papillary thyroid cancer ≤1 cm in size and the existing clinical data of regional and distant metastases. All patients underwent thyroidectomy with bilateral central cervical lymph node dissection. Factors such as gender, patient age, bilaterality, extrathyroid extension, the presence or absence of a capsule around the tumor node, the absence or presence of metastases in the central part were assessed. In 26.6% histological examination revealed metastatic lesions of the central group lymph nodes. Latent metastases were detected in 24.2% of women and 43% of men, in 36.7% of patients <55 and in 14.3% of patients ≥ 55 years, in 29.5% with the absence of the node capsule and in 19.3% with encapsulated tumors, in 48.1% with multicentric growth and in 19.5% with a solitary neoplasm, in 21.7% with a tumor size ≤0.5 cm and in 27.9% with a node of 0.6–1 cm, in 24% with the absence of invasion of the thyroid capsule and in 31% with the presence of extrathyroid invasion, in 21% of patients with typical, in 26% with follicular and 43% with mixed papillary cancer. 95 patients received radioiodine therapy. No additional metastases were found in them.Results. When conducting univariate analysis, the main signs influencing the development of metastases in the central zone were age up to 55 years (p = 0.009, χ2 = 6.919) and multicentric neoplasm (p = 0.004, χ2 = 8.530); in multivariate analysis, similarly, age younger 55 years (p = 0.000, Exp B = 0.011, CI 95.0% 0.001–0.106) and multifocality (p = 0.027, Exp B = 2.686, CI 95.0% 1.119–6.448).Conclusion. PTMC is not a separate group or tumor morphotype, and the determination of treatment tactics for this group of patients should be based not only on the size of the tumor, but on the clinical and biological parameters of the tumor.

Selecting the Right Plane of Dissection in Thyroidectomy: Along the Recurrent Laryngeal Nerve or the Thyroid Capsule? A Retrospective Analysis

Introduction Total thyroidectomy remains highly technical, with a significant risk of recurrent laryngeal nerve (RLN) compromise and hypoparathyroidism. After identifying RLN, at the level of the ligament of Berry, local factors may compel the surgeon to either dissect along the nerve or the thyroid capsule. Objective The objective of the present study is to compare these two approaches in terms of outcomes and complication rates. Methods This is a retrospective analysis from September, 2013 to April 2019 of 511 consecutive patients undergoing thyroidectomy. General demographics and disease parameters were recorded. At the discretion of the surgeon and according to the demands of the local operative factors, the patients either had dissection along the RLN or along the thyroid capsule. Perioperative and postoperative parameters such as blood loss, duration of surgery, hospital stay, pain scores, analgesia requirements and complications were recorded. The groups were compared with the Pearson chi-squared test or with the Fisher exact test. A p-value < 0.05 was considered statistically significant. Results The incidence of transient hypocalcaemia and transient RLN compromise were higher when dissection was performed along the nerve as opposed to the plane along the thyroid capsule. Other parameters including operative time, hospital stay, pain scores, analgesia requirement, wound infection, seroma, hemorrhage, and recurrence did not differ between the groups. Subgroup analysis of the patients who presented with complications showed that local factors, malignancy, and extent of surgery correlated positively with complications when dissected along the RLN. Conclusion Dissection along the capsule of the thyroid during thyroidectomy is a safer plane in terms of low rate of transient RLN injury and hypoparathyroidism as opposed to dissection along the nerve.

Multi-modal Ultrasonic Diagnosis and Prognosis for Primary Thyroid Lymphoma Invasiveness

Objective Sixty-nine patients with primary thyroid lymphoma (PTL) were evaluated for diagnostic value and prognosis for PTL invasiveness. Methods We retrospectively (2008–2019) analyzed multi-modal ultrasonic images and clinical characteristics from pathologically confirmed PTL patients. These patients were divided into aggressive PTL(n=46) and indolent PTL(n=23). Results Age(>70 years old) and elevated LDH (lactase dehydrogenase) were statistically different clinical features between aggressive and indolent PTL. From ultrasonic images, 34 cases were nodular, 11 diffused, and 24 mixed. Mixed types displayed high invasiveness (45.7%) while diffuse types displayed higher inertness (39.1%), and differences were statistically significant (P = 0.000). Elastography, invaded thyroid capsule and increased chaotic vascularity also showed significant differences between aggressive and indolent PTL. We observed statistical difference in OS(overall survival rates) between aggressive and indolent PTL(p=0.032). Single factor Kaplan-Meier (K-M) analysis showed that: age > 70 years old, aggressive pathology, Ki67>30%, elastography scored >3 were positively correlated with the risk of poor prognosis of PTL (P < 0.05).Conclusions Multi-modal ultrasound provides accurate ultrasonographic information, e.g., ultrasound patterns, elastography, invaded thyroid capsules, and hypervascularity, which facilitates PTL invasiveness diagnostics for improved clinical treatment. In addition, PTL patients with age > 70 years old, aggressive pathology, Ki67>30%, elastography scored >3 are more likely to have poor prognosis.

Truncal vs Branch Ligation of Inferior Thyroid Arteries in Total Thyroidectomy: Does It Affect Postoperative Hypoparathyroidism?

Objective Postthyroidectomy hypoparathyroidism remains a significant challenge. Truncal ligation of the inferior thyroid arteries (ITAs) may lead to an increased risk of hypoparathyroidism; however, dissection along the thyroid capsule with branch ligation of the thyroid arteries could be a safer option. This study’s objective was to compare the effect of truncal versus branch ligation of the ITAs on the rate of postoperative hypoparathyroidism. Study Design Randomized prospective trial in line with the CONSORT guidelines. Setting The study was conducted at a high-volume tertiary care setting. Methods We randomized 319 patients into 2 groups: truncal ITA ligation (n = 157) and branch ITA ligation (n = 162). The primary outcomes were serum calcium and parathormone levels on the second postoperative day, followed by the levels on months 1, 3, 6, and 12. The need for exogenous replacements was noted. The secondary outcomes, such as operative time, blood loss, and other complications, were also recorded. Results Our study revealed a significant difference in the incidence of transient hypocalcemia in patients undergoing truncal ITA ligation and branch ITA ligation (22.9% vs 3.1%, P < .05). The results showed that the levels of serum calcium and parathormone dropped on the second postoperative day and that 36 patients from the truncal ITA ligation group required exogenous calcium and vitamin D replacement. In contrast, only 5 patients from the branch ITA ligation group required the same. Conclusions This is the largest randomized trial of patients undergoing thyroidectomy, and it shows that dissection along the thyroid capsule with branch ligation of the ITAs is more likely to preserve parathyroid function as opposed to truncal ligation of ITAs.

SAT-LB77 Thyroid Radiofrequency Ablation: A New Office Based Procedure for Endocrinologists

Recent FDA approval of thyroid RF has made it possible for endocrinologists in the USA to finally treat their own patients after obtaining training. I have 5 years experience working with these systems and have trained many endocrinologists in my practice. In 2019 I began a preliminary study of 12 patients with negative biopsies to see the feasibility of doing thyroid RF in my ultrasound room in my office without going to imaging centers or the hospital. The fee for office based RF is 3-6 times less expensive. RF system by RF Medical Korea was used in all cases. The results are promising. Skin and thyroid capsule local injection was all that was needed for pain control. Vital signs were monitored by my roving nurse. The maximal watts used was 20-40. There were no major complications and only one bruise in the neck area. No vocal symptoms. All 12 tolerated the procedure and after 30 minutes observation left with only a small band aid over the injection site. Two flew out of state that night.Conclusion: A preliminary assessment of in office thyroid RF without general of conscience sedation by trained endocrinologists suggests larger study with 80-100 cases is the next step.