Extent Of Central Neck Dissection Research Articles

Risk factors of transient and permanent hypoparathyroidism after thyroidectomy: a systematic review and meta-analysis.

Postoperative hypoparathyroidism (hypoPT) is a common complication following thyroid surgery. However, current research findings on the risk factors for post-thyroid surgery hypoPT are not entirely consistent, and the same risk factors may have different impacts on transient and permanent hypoPT. Therefore, there is a need for a comprehensive study to summarize and explore the risk factors for both transient and permanent hypoPT after thyroid surgery. Two databases (PubMed and Embase) were searched from inception to 2024. The Newcastle-Ottawa Scale was used to rate study quality. Pooled odds ratios (OR) were used to calculate the relationship of each risk factor with transient and permanent hypoPT. Subgroup analyses were conducted for hypoPT with different definition-time (6 or 12mo). Publication bias was assessed using Begg's test, and Egger's test. A total of 19 risk factors from the 93 studies were included in the analysis. Among them, sex and parathyroid autotransplantation were the most frequently reported risk factors. Meta-analysis demonstrated that sex (female vs. male), cN stage, central neck dissection, lateral neck dissection, extent of central neck dissection (bilateral vs. unilateral), surgery (total thyroidectomy (TT) vs. lobectomy), surgery type (TT vs. sub-TT), incidental parathyroidectomy, and pathology (cancer vs. benign) were significantly associated with transient and permanent hypoPT. Preoperative calcium and parathyroid autotransplantation were only identified as risk factors for transient hypoPT. Additionally, node metastasis and parathyroid in specimen were associated with permanent hypoPT. The highest risk of hypoPT occurs in female thyroid cancer patients with lymph node metastasis undergoing TT combined with neck dissection. The key to preventing postoperative hypoPT lies in the selection of surgical approach and intraoperative protection.

Occult contralateral central neck metastasis in papillary thyroid carcinoma with preoperatively documented ipsilateral lateral neck metastasis

BackgroundThis study was conducted to evaluate risk factors and long-term prognosis of contralateral central neck metastasis (CCNM) in papillary thyroid cancer (PTC) patients with ipsilateral lateral neck metastasis. We present clinical evidence to aid in surgical decision-making regarding the extent of central neck dissection (CND), focusing on separation between ipsilateral and contralateral sides. MethodsA total of 379 PTC patients who underwent total thyroidectomy and concomitant bilateral central neck dissection with ipsilateral lateral neck dissection (LND) at a single institution was retrospectively included between January 1997 and December 2015. ResultsThe median follow-up time was 83.2 months, the mean age was 44.3 years, and the mean tumor size was 1.5 cm. Among the study sample, 266 patients were female (70.2%) and 113 (29.8%) were male. Of 379 patients, CCNM was present in 34.6%. In multivariate analysis, male sex (adjusted OR = 2.46, p = 0.002), bilaterality (adjusted OR = 2.58, p = 0.004), number of metastatic ipsilateral central lymph nodes (adjusted OR = 1.15, p = 0.002), number of metastatic lateral lymph nodes (adjusted OR = 1.48, p < 0.001), and three-level metastasis (adjusted OR = 2.46, p = 0.012) were identified as risk factors of CCNM. Overall recurrence occurred in 6.0% and 11.5% of patients in the CCNM (-) group and CCNM (+) group, respectively. In addition, contralateral recurrence was observed in 1.2% patients and 0.8% patients in the CCNM (-) group and CCNM (+) group, respectively. However, CCNM did not significantly increase risk of recurrence (adjusted HR = 1.01, p = 0.981). ConclusionsAlthough the probability of pathological CCNM is not negligible, CCNM was not associated with higher risk of recurrence. This study suggest that central neck dissection may be limited to the ipsilateral side, and the result regarding prognosis of CCNM may help to avoid bilateral CND so that it could have potential to minimize unnecessary surgery-related complications such as recurrent laryngeal nerve(RLN) injury or hypoparathyroidism.

The predictive factors for postoperative hypoparathyroidism and its severity on the first postoperative day after papillary thyroid carcinoma surgery.

The purpose of the study was to investigate the predictive factors for hypoparathyroidism and its severity on the first postoperative day (POD1) after total thyroidectomy (TT) with or without central neck dissection (CND) in patients with papillary thyroid carcinoma (PTC). From February 2014 to February 2019, 2550 PTC patients were admitted to our department. PTC patients who underwent TT were enrolled in this study. A parathyroid hormone (PTH) level lower than 15pg/mL on POD1 was defined as hypoparathyroidism, and the severity of hypoparathyroidism was classified into three categories according to the level of PTH on POD1: mild hypoparathyroidism (10pg/mL ≤ PTH < 15pg/mL), moderate hypoparathyroidism (5g/mL ≤ PTH < 10pg/mL), and severe hypoparathyroidism (PTH < 5pg/mL). Multiple clinical, pathological and surgical parameters of these two different groups were compared and analyzed to demonstrate the possible causes of hypoparathyroidism. Furthermore, patients who developed postoperative hypoparathyroidism were also included in a subgroup analysis according to the severity of their hypoparathyroidism. The underlying factors affecting different severities of hypoparathyroidism were also illustrated with univariate and multivariate analyses. Ultimately, 690 patients who underwent TT were enrolled in this retrospective study. Through the univariate analysis, different surgeons (P < 0.001), extent of CND (P = 0.009), prophylactic calcium supplementation (PCS) (P < 0.001), preoperative (pre-op) PTH level (P < 0.001), and pre-op phosphorus concentration (P = 0.022) were found to be significantly correlated with postoperative hypoparathyroidism. According to the multivariate analysis, PCS was the only independent high-risk factor for hypoparathyroidism. In the univariate analysis of patient subgroups with different severities of hypoparathyroidism, we demonstrated that the tumor T stage (P = 0.021) and pre-op PTH level (P < 0.001) were associated with the severity of hypoparathyroidism. Furthermore, after the multivariate analysis, hypertension (P < 0.001) and pre-op PTH (P < 0.001) were the two independent predictive factors for the severity of hypoparathyroidism after surgery. Postoperative PCS could increase the risk for PTC patients developing hypoparathyroidism after thyroid surgery. Patients with a history of hypertension and a relatively high pre-op PTH level may not develop severe hypoparathyroidism after TT with CND.

Indications and extent of central neck dissection for papillary thyroid cancer: An American Head and Neck Society Consensus Statement.

The primary purposes of this interdisciplinary consensus statement were to review the relevant indications for central neck dissection (CND) in patients with papillary thyroid cancer (PTC) and to outline the appropriate extent and relevant techniques required to accomplish a safe and effective CND. A writing group convened by the American Head and Neck Society (AHNS) Endocrine Committee was tasked with identifying the important clinical elements to consider when managing the central neck compartment in patients with PTC based on available evidence in the literature, and the group's collective experience. The position statement paper was then submitted to the full Endocrine Committee, Education Committee, and AHNS Council. This consensus statement was developed to inform the clinical decision-making process when managing the central neck compartment in patients with PTC from the AHNS. This document is intended to provide clarity through definitions as well as a basic guideline from which to manage the central neck. It is our hope that this improves the quality and reduces variation in management of the central neck, facilitates communication, and furthers research for patients with thyroid cancer. This represents, in our opinion, contemporary optimal surgical care for this patient population and is endorsed by the American Head and Neck Society. © 2017 Wiley Periodicals, Inc. Head Neck 39: 1269-1279, 2017.

Predictors and risk factors of hypoparathyroidism after total thyroidectomy

BackgroundThe aim of this study was to evaluate the risk factors for hypoparathyroidism after total thyroidectomy and to determine whether early postoperative serum levels of calcium and phosphorus could be used to predict its development. Materials and MethodsThe study group consisted of 1030 patients who had undergone total thyroidectomy at our institution between March 2008 and July 2014. The clinicopathologic characteristics, indications for the operation, and surgical details of normocalcemic and hypocalcemic patients were compared, and variations in serum calcium and phosphorus levels were measured every day after the operation. ResultsOf the 1030 patients, 291 (28.2%) were found to have transient hypocalcemia and 27 (2.6%) had permanent hypocalcemia. On univariate analysis, younger age (P = 0.001), female gender (P < 0.001), longer operative time (P = 0.009), extent of central neck dissection (CND) (P = 0.003), and malignancy (P = 0.005) were found to be significantly associated with transient hypocalcemia. On multivariate analysis, female gender (P = 0.001), extent of CND (P = 0.017), and the identification of parathyroid gland (PTG) tissue in permanent pathologic sections were significant factors. In addition, the occurrence of postoperative hypocalcemia was correlated with relative changes in serum calcium and phosphorus levels. Patients whose serum calcium levels decreased over 20% on postoperative day 2 were more likely to develop hypoparathyroidism, with 92% specificity. ConclusionFemale gender (P = 0.001), extent of CND (P = 0.014), and PTG in permanent pathologic sections (P = 0.035) were found to be significant factors affecting the development of hypocalcemia. Despite some study limitations, we suggest that the relative changes in the serum levels of calcium (20%) and of phosphorus (40%) on the second postoperative day may be reliable predictors of post-thyroidectomy hypoparathyroidism.

Oncologic outcomes of robotic thyroidectomy: 5-year experience with propensity score matching.

The oncologic outcome of robotic thyroidectomy is not yet well established. The aim of this study was to evaluate the recurrence rate after robotic thyroidectomy in comparison with conventional thyroidectomy for papillary thyroid carcinoma (PTC). We analyzed 896 patients with PTC who either underwent robotic (212 patients using a gasless unilateral axillary or an axillo-breast approach) or conventional cervical thyroidectomy (684 patients) with/without central neck dissection between October 2008 and February 2014. We excluded patients who underwent concomitant lateral neck dissection or completion thyroidectomy, and cases with T4 tumor, tumor lager than 4cm, other types of thyroid cancer, recurrent cancer, and distant metastasis. A propensity score matching analysis was done with ten covariates including age, gender, body mass index, tumor size, multifocality, bilaterality, extrathyroidal extension, type of thyroidectomy, extent of central neck dissection, and RAI ablation to reduce selection bias. In baseline data, the male ratio and the mean age were lower in the robotic group. Stage, multifocality, and bilaterality were higher in the conventional group. The rate of total thyroidectomy was higher in the conventional group. The two matched groups of each 185 patients were produced and well balanced by propensity score matching. In the comparison of propensity score matched groups, operative time was longer in the robotic group (P<0.001), and postoperative complications did not differ between the two groups, except for transient hypoparathyroidism and formation of seroma. The recurrence rate did not differ between the two groups after a mean follow-up of 43.6months (0.5 and 1.1% in the robotic and conventional groups, respectively, P=0.375). The oncologic outcome of robotic thyroidectomy in 5-year experience is comparable to that of conventional thyroidectomy in selected patients with PTC.

Extent of central neck dissection among thyroid cancer surgeons: Cross-sectional analysis.

It is unclear if surgeons are performing comprehensive central neck dissections for well-differentiated thyroid cancer. The purpose of this study was to determine mean lymph node retrieval in central neck dissection as well as variability across surgeons and institutions. A prospectively collected database identified 18 surgeons performing 425 central neck dissections, 313 unilateral and 112 bilateral. Demographics, perioperative, and pathologic factors were analyzed. Mean lymph node yield was 7.4 and 11.9 for unilateral and bilateral central neck dissection, respectively. Although 224 central neck dissections were prophylactic, both total and pathologic lymph node yields were significantly higher in therapeutic central neck dissection. There was a significant variation in lymph node yield across individual surgeons, institutions, and regions. High-volume central neck dissection surgeons have significantly lower lymph node yield compared to low-volume surgeons. Central neck dissection seems to be performed adequately; however, there is a significant variation in lymph node yield. Future initiatives should try to standardize the central neck dissections performed, with emphasis on obtaining a sufficient yield. © 2015 Wiley Periodicals, Inc. Head Neck 38: E328-E332, 2016.

Prophylactic neck dissection in papillary thyroid cancer: When is it necessary?

BACKGROUND The American Cancer Society estimates that there will be approximately 56,460 new diagnoses of thyroid cancer in the United States during 2012, and more than 90% will be papillary thyroid cancer (PTC). Despite the large, ever-increasing number of thyroid cancer cases, the ideal initial management of well-differentiated PTC remains controversial. The role of the prophylactic central neck dissection (pCND) has emerged as the most highly debated topic, with conflicting reports regarding indications, recurrence prevention, and reduction of cause-specific mortality. Currently, there is no argument that a formal, compartmental CND should be performed if preoperative or palpable nodal disease is encountered. However, the 2009 American Thyroid Association (ATA) guidelines state that, “Prophylactic central compartment neck dissection may be performed in patients with papillary thyroid carcinoma with clinically uninvolved central neck lymph nodes, especially for advanced primary tumors (T3 or T4; Grade C recommendation; expert opinion).” With the advent of personalized therapy based on molecular testing, the BRAF gene has shown the most promise in predicting lymph node metastases and may be used to direct clinicians on whether to perform a pCND. The focus of the review will seek to answer the question of best practice with regards to pCND in PTC. LITERATURE REVIEW Due to the excellent outcomes seen with PTC, the importance of lymph node metastases has been difficult to interpret. Recent, large, population-based studies have demonstrated a decrease in cause-specific survival in lymph-node positive PTC patients. Zaydfudim et al. used the Surveillance, Epidemiology, and End Results database to analyze outcomes of 30,054 patients with PTC. They concluded through multivariate analysis that metastatic LNs conveyed a 46% increased risk of death (HR, 1.46; P<.001) in patients 45 years, even with the majority of patients with excellent long-term survival. However, in patients< 45, lymph node status did not influence survival. While the presence of metastatic positive lymph nodes in PTC may dictate a decrease in cause-specific survival, does performing a prophylactic central neck dissection actually improve the patient’s outcome? A meta-analysis of five studies with a total of 1,264 patients demonstrated a decrease in lymph node recurrence (2% vs. 3.9%) in the thyroidectomy1pCND group, but this did not achieve statistical significance. The rate of transient recurrent laryngeal nerve paralysis (1.8%–5.4% thyroidectomy1pCND, 1%–1.3% thyroidectomy alone) and transient hypoparathyroidism (18%– 44% thyroidectomy1pCND, 8%–14% thyroidectomy alone (P< 0.02)) was higher in the group receiving pCND. Permanent recurrent nerve paralysis and hypocalcemia were not different between the two arms. The authors concluded that the balance between the risks and benefits favored thyroidectomy alone. However, they recognized several limitations to the study: inclusion of retrospective data, inconsistencies in the use of RAI and thyroid suppression postoperatively, limited data on timing of recurrence, and a lack of standardized reporting with regard to the extent of central neck dissection (ipsilateral vs. bilateral, etc.). The authors conclude with the call for a large, prospective trial to fully resolve the controversy. However, the feasibility of such a randomized trial was investigated by the ATA, which concluded that prohibitively large sample sizes (5,840 patients) and approximately $20 million would be required to demonstrate significant differences in outcomes. From the Louisiana State University Health Sciences Center– Shreveport, Department of Otolaryngology/Head and Neck Surgery, Shreveport, Louisiana, U.S.A.

Differentiated Thyroid Cancer: Indications and Extent of Central Neck Dissection—Our Experience

The aim of this retrospective study was to determine the rate of metastases in the central neck compartment and examine the morbidity and rate of recurrence in patients with differentiated thyroid cancer treated with or without a central neck dissection. Two hundred and fifteen patients undergoing total thyroidectomy with preoperative diagnosis of differentiated thyroid cancer, in the absence of suspicious nodes, were divided in two groups: those who underwent a thyroidectomy only (group A; n = 169) and those who also received a central neck dissection (group B; n = 46). Five cases (2.32%) of nodal recurrence were observed: 3 in group A and 2 in group B. Tumor histology was associated with a risk of recurrence: Hürthle cell-variant and tall cell-variant carcinomas were associated with a high risk of recurrence. Multifocality and extrathyroidal invasion also presented a higher risk, while smaller tumors were at lower risk. The results of this study suggest that prophylactic central neck dissection should be reserved for high-risk patients only. A wider use of immunocytochemical and genetic markers to improve preoperative diagnosis and the development of methods for the intraoperative identification of metastatic lymph nodes will be useful in the future for the improved selection of patients for central neck dissections.

Impact of lymph node metastases identified on central neck dissection (CND) on the recurrence of papillary thyroid cancer: potential role of BRAFV600E mutation in defining CND

The impact of metastasized cervical lymph nodes (CLN) identified on central neck dissection (CND) on the recurrence/persistence of papillary thyroid cancer (PTC) and the extent of CND needed to reduce recurrence/persistence have not been firmly established. To assess the impact of CLN metastasis and BRAF mutation on the recurrence/persistence of PTC and the potential of BRAF mutation in assisting CND. Analyses of 379 consecutive patients with PTC who underwent thyroidectomy with (n=243) or without CND (n=136) at a tertiary-care academic hospital during the period 2001-2010 for their clinicopathological outcomes and BRAF mutation status. Increasingly aggressive tumor characteristics were found as the extent of CND was advanced following conventional risk criteria from non-CND to limited CND to formal CND. Disease recurrence/persistence rate also sharply rose from 4.7% to 15.7% and 40.5% in these CND settings respectively (P<0.0001). CLN metastasis rate rose from 18.0 to 77.3% from limited CND to formal CND (P<0.0001). An increasing rate of BRAF mutation was also found from less to more extensive CND. A strong association of CLN metastasis and BRAF mutation with disease recurrence/persistence was revealed on Kaplan-Meier analysis and BRAF mutation strongly predicted CLN metastasis. CLN metastases found on CND are closely associated with disease recurrence/persistence of PTC, which are both strongly predicted by BRAF mutation. Current selection of PTC patients for CND is appropriate but higher extent of the procedure, once selected, is needed to reduce disease recurrence, which may be defined by combination use of preoperative BRAF mutation testing and conventional risk factors of PTC.

Related factors of central lymph node metastasis in papillary thyroid carcinoma

To study the related factors of central lymph node (CLN) metastasis in papillary thyroid carcinoma (PTC),the indications and the extent of central neck dissection (CND). A total of 153 cases treated between Jan. 2009 and Dec. 2010 was analysed retrospectively. Of the cases 28 males and 125 cases females, with a mean age of (44 ± 14) years. T1, T2, and T3 diseases accounted for 51, 10 and 81 cases, respectively; I, II, III and IV diseases for 88, 3, 26 and 36 cases, respectively. Multifocal tumors were found in 63 cases. The related clinicopathologic factors were analyzed, including sex, age, tumor size, extrathyroidal extension, and multifocal tumor. All the cases had total/near total thyroidectomy and CND, of them 64 cases had unilateral neck dissection and 18 cases had bilateral neck dissection. CLN metastases existed in 68.6% (105/153) cases, 37.2% (57/153) for unilateral and 31.4% (48/153) for bilateral respectively. The rates of CLN metastasis were 86.6% (71/82) in cN1 cases and 47.9% (34/71) cN0 cases, respectively,and the rates of bilateral CLN metastases were 45.1% (37/82) in cN1 cases and 15.5% (11/71) in cN0 cases. Multivariate analysis showed that extrathyroidal extension (P = 0.002, OR = 3.502) was an independent risk factor for CLN metastasis and that lateral neck lymph node metastasis (P = 0.028, OR = 3.080), surrounding tissue invasion (P = 0.014, OR = 3.113), and maximum tumor diameter greater than 1 cm (P = 0.012, OR = 3.732) were independent risk factors for bilateral CLN metastases. It is indicated that ipsilateral CND should be obligatory for PTC. Intraoperative frozen section examination should be routine. Bilateral CND should be conducted when ipsilateral CLN metastases accompanied by one of following issues such as more invasive tumor (surrounding tissue invasion, T3 or T4 disease), maximum tumor diameter greater than 1 cm, and lateral neck lymph node metastasis.