Yanping Gong

Prediction of nonrecurrent laryngeal nerve before thyroid surgery—experience with 1825 cases

BACKGROUND Nonrecurrent laryngeal nerve (NRLN) is a rare anatomic anomaly, which often co-occurs with aberrant right subclavian artery (ARSA). With this large case series, we present our experience of predicting the presence of NRLN by the means of chest X-ray film, thoracic computed tomography (CT), and ultrasonography. MATERIALS AND METHODS A prospective, nonrandomized study has been carried out. A total of 1825 patients with various thyroid disorders scheduled for surgery were recruited between January 2006 and July 2012. All patients underwent preoperative chest X-ray examination. Those suspected with ARSA further underwent thoracic CT scan. Unsuspected patients who had NRLN revealed by surgery were analyzed with ultrasonography postoperatively. RESULTS A total of 41 patients (2.25%) were suspected to have ARSA by X-ray, of those 19 (46.3%) were confirmed by thoracic CT and proven to have NRLN upon subsequent surgery. No NRLN injury was inflicted. For the remaining 22 cases, CT scan suggested a normal right subclavian artery and none had NRLN upon surgery. For the 1784 unsuspected patients, 4 (0.22%) were discovered to have NRLN upon surgery, of those one was injured. For the 19 predicted NRLN, the time used for identifying the nerve was significantly shorter than the four cases with unsuspected NRLN (t = -15.978; P = 0.000). After the operation, all these unsuspected NRLN were confirmed to have ARSA by ultrasonography. CONCLUSIONS Patients scheduled for thyroid surgery should be screened for ARSA upon routine chest X-ray and thyroid ultrasonography before surgery. Detection of ARSA can accurately predict the existence of NRLN; hence prevent NRLN injury during subsequent surgery.

Association of the preoperative neutrophil-to-lymphocyte and platelet-to-lymphocyte ratios with lymph node metastasis and recurrence in patients with medullary thyroid carcinoma

AbstractThe preoperative neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) are known to be prognostic factors in several cancers. However, no previous investigation has been performed to evaluate the significance of the NLR and PLR in medullary thyroid carcinoma (MTC).The aim of this study was to identify the ability of the preoperative NLR or PLR to predict lymph node metastasis and recurrence in patients with MTC. Data from all patients with MTC who had undergone surgery at our institution from May 2009 to May 2016 were retrospectively evaluated. Receiver operating characteristic (ROC) analysis was performed to identify optimal NLR and PLR cutoff points, and we assessed independent predictors of lymph node metastasis and recurrence using univariate and multivariate analyses.Based on the inclusion and exclusion criteria, a total of 70 patients were enrolled in this study. The ideal cutoff points for predicting lymph node involvement were 2.7 for the NLR and 105.3 for the PLR. The optimal cutoff points of the NLR and PLR for predicting recurrence were 2.8 and 129.8, respectively. Using the cutoff values, we found that PLR>105.3 (odds ratio [OR] 4.782, 95% confidence interval [CI] 1.4–16.7) was an independent predictor of lymph node metastasis and that PLR>129.8 (OR 3.838, 95% CI 1.1–13.5) was an independent predictor of recurrence.Our study suggests that the preoperative PLR, but not NLR, was significantly associated with lymph node metastasis and recurrence in patients with MTC.

Risk factors of hypoparathyroidism following total thyroidectomy with central lymph node dissection

Abstract The risk factors of hypoparathyroidism after total thyroidectomy (TT) with central lymph node dissection (CND) have not been completely defined. The aim of the study was to evaluate the risk factors of hypoparathyroidism after the surgery. We retrospectively reviewed our patients who underwent TT and CND (including lateral lymph node dissection) for thyroid carcinoma between January 2013 and June 2016. According to the postoperative serum levels of parathyroid hormone within 6 months, the patients were divided into normal, transient hypoparathyroidism, and permanent hypoparathyroidism groups. The clinicopathologic characteristics and surgical details were compared among the 3 groups. The risk factors of hypoparathyroidism were investigated by univariate and multivariate analyses. Of the 903 patients, 399 (44.2%) were found to have transient hypoparathyroidism and 10 (1.1%) had permanent hypoparathyroidism. On multivariate analysis, female gender (P < .001), nonuse of carbon nanoparticles (P = .038), parathyroid autotransplantation (P < .001), accidental parathyroid resection (P = .004), and bilateral CND (BCND, P = .003) were the independent risk factors of transient hypoparathyroidism; nonuse of carbon nanoparticles (P = .041) and a tumor in the upper pole of thyroid gland (P = .031) were the independent risk factors of permanent hypoparathyroidism. Patients with transient hypoparathyroidism were more likely to develop permanent hypoparathyroidism when they had hypertension (P = .026) and a tumor in the upper pole of thyroid gland (P = .010). Precise surgical techniques and carbon nanoparticles suspension should be applied for in situ preservation of parathyroid glands (PGs) in thyroid carcinoma patients, especially in females with hypertension and a tumor in the upper pole of thyroid gland. Autotransplantation is only performed when a PG is resected inadvertently or devascularized. TT with BCND should be better performed by an experienced surgeon to reduce the incidence of hypoparathyroidism.

Risk factors for level V lymph node metastases in solitary papillary thyroid carcinoma with clinically lateral lymph node metastases

The extent of lateral neck dissection (LND) in surgical resection of papillary thyroid carcinoma (PTC) with clinically lateral LNM (LLNM) remains controversial. We aimed to explore the frequency of and risk factors for level V LNM in patients with solitary PTC and clinically LLNM. To analyze the frequency and risk factors for level V LNM, we retrospectively reviewed 220 solitary PTC patients who underwent total thyroidectomy, bilateral central neck dissection, and therapeutic LND. LLNM were present in 82.3% patients, and levels II–V LNM were present in 45.9%, 62.7%, 55.5%, and 12.3% patients, respectively. Ipsilateral level V LNM was significantly associated with tumor size >10 mm, extrathyroidal extension, ipsilateral central LNM ratio ≥50%, and contralateral central LNM (CLNM), bilateral CLNM, and simultaneous levels II–IV LNM. Contralateral CLNM was an independent risk factor for level V LNM. In patients with solitary PTC and clinically LLNM, level V LNM was relatively uncommon. Therefore, routine level V lymphadenectomy may be unnecessary in these patients unless level V LNM is suspected on preoperative examination or associated risk factors, especially contralateral CLNM, are present.

Novel Management of Intractable Cervical Chylous Fistula with Local Application of Pseudomonas aeruginosa Injection

Objective Cervical chylous fistula is an uncommon complication after neck dissection, but it might lead to some serious clinical outcomes. Although most cervical chylous fistulas can heal in a few days with standard treatments, some can be intractable. In this study, we describe a new method with local application of Pseudomonas aeruginosa injection for intractable cervical chylous fistula. Study Design Case series with chart review. Setting West China Hospital, Sichuan University, Chengdu, China. Subjects and Methods The charts of 18 patients who were treated with P aeruginosa injection (PAI) for intractable cervical chylous fistula were retrospectively reviewed. Results All patients were successfully treated with PAI. Mild fever (temperature, <38°C) occurred in 9 patients, moderate fever (38°C-39°C) in 4 patients, and severe fever (>39°C) in 5 patients. All patients had mild to severe neck pain. Conclusions Local application of PAI is an effective method for the treatment of intractable cervical chylous fistula, of which the most common side effects are transient fever and local pain.

Does the number of parathyroid glands autotransplanted affect the incidence of hypoparathyroidism and recovery of parathyroid function

Background: The relationship between the number of parathyroid glands autotransplanted and hypoparathyroidism as well as recovery of parathyroid function is not understood fully. The aim was to ascertain whether the number of autotransplanted glands affected the incidence of hypoparathyroidism and recovery of parathyroid function in long‐term follow‐up after thyroidectomy. Methods: A retrospective cohort study included all patients with papillary thyroid carcinoma who underwent first‐time total thyroidectomy with central neck dissection between June 2012 and June 2015. The patients were divided into 4 groups (0, 1, 2, and 3) on the basis of the number of parathyroid glands autotransplanted. Results: Of the 766 patients, 283 (36.9%) had no gland autotransplanted, and 373 (48.7%), 97 (12.7%), and 13 (1.7%) had 1, 2, and 3 glands autotransplanted, respectively. More lymph nodes and more metastatic ones in the central compartment were retrieved in groups 2 and 3 (P < .05). With increasing number of autotransplanted glands, the incidence of transient hypoparathyroidism was 26.1%, 36.2%, 52.6%, and 84.6% (P < .05), and the incidence of permanent hypoparathyroidism was 1.8%, 1.1%, 1.0%, and 0% (P > .05). The recovery rates of serum parathyroid hormone concentration were 84.7%, 82.2%, 82.0%, and 79.2% after 2‐year follow‐up (P > .05). Conclusion: Autotransplantation is an effective strategy for restoration of parathyroid function. Transient hypoparathyroidism is positively correlated to the number of autotransplanted parathyroid glands during total thyroidectomy with central neck dissection. There is no increase in permanent hypoparathyroidism in patients with a higher number of autotransplanted glands, despite more extensive lymph node disease. (Surgery 2018;161:XXX‐XXX.)

Preserved SCN4B expression is an independent indicator of favorable recurrence-free survival in classical papillary thyroid cancer

Voltage-gated sodium channel β subunits (encoded by SCN1B to SCN4B genes) have been demonstrated as important multifunctional signaling molecules modulating cellular processes such as cell adhesion and cell migration. In this study, we aimed to explore the expression profiles of SCN4B in papillary thyroid cancer (PTC) and its prognostic value in terms of recurrence-free survival (RFS) in classical PTC. In addition, we also examined the potential effect of DNA methylation on its expression. A retrospective study was performed by using data from available large databases, including the Gene Expression Omnibus (GEO) datasets and the Cancer Genome Atlas (TCGA)-Thyroid Cancer (THCA). Results showed that SCN4B is downregulated at both RNA and protein level in PTC compared with normal thyroid tissues. Preserved SCN4B expression was an independent indicator of favorable RFS in patients with classical PTC, no matter as categorical variables (HR: 0.243, 95%CI: 0.107–0.551, p = 0.001) or as a continuous variable (HR: 0.684, 95%CI: 0.520–0.899, p = 0.007). The methylation status of one CpG site (Chr11: 118,022,316–318) in SCN4B DNA had a moderately negative correlation with SCN4B expression in all PTC cases (Pearson’s r = -0.48) and in classical PTC cases (Pearson’s r = -0.41). In comparison, SCN4B DNA copy number alterations (CNAs) were not frequent and might not influence its mRNA expression. In addition, no somatic mutation was found in SCN4B DNA. Based on these findings, we infer that preserved SCN4B expression might independently predict favorable RFS in classical PTC. Its expression might be suppressed by DNA hypermethylation, but is less likely to be influenced by DNA CNAs/mutations.

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.

Protocol for management after thyroidectomy: a retrospective study based on one-center experience

Background and aim The optimal approach to detect and treat symptomatic hypocalcemia (SxH) after thyroidectomy is still uncertain. In our retrospective study, we sought to set a standardized postoperative management protocol on the basis of relative change of parathyroid hormone (PTH) and absolute value of postoperative day 1 (POD1) PTH. Methods Patients who underwent thyroidectomy were identified retrospectively in our prospective database. Blood was collected 1 day before surgery and on POD1. Extra calcium and calcitriol supplement was prescribed when necessary. Meanwhile, postoperative signs of SxH were treated and recorded in detail. Patients were followed up for 1 month after surgery and then 3 months thereafter. Results A total of 744 patients were included in the final analysis. Transient SxH occurred in 86 (11.6%) patients, and persistent SxH occurred in 4 (0.54%) patients in more than half year after surgery. Relative decrease of PTH reached its maximal discriminative effect at 70% (area under the curve [AUC] =0.754), with a sensitivity of 72.1% and a specificity of 75%. In Group 1 (≤70%), 24 (4.67%) patients were interpreted as having SxH, whereas in Group 2, 62 (27.0%) patients had SxH (>70%), P<0.001. Days of symptom relief in Group 1–1 (1, 2) were significantly shorter than those in Group 2–2 (1, 10), P=0.023. In Group 2, 112 (80%) patients with POD1 PTH <1 pmol/L were treated with calcitriol, whereas only 8 (8.89%) patients with POD1 PTH ≥1 pmol/L were treated with calcitriol (P<0.001). According to relief of SxH and recovery of parathyroid function, treating with and without calcitriol showed no difference in patients with POD1 PTH <1 and ≥1 pmol/L. Conclusion Relative decrease of PTH >70% is a significant risk factor for SxH in post-thyroidectomy. The decreasing percent of PTH ≤70% ensures discharge on POD1, but longer hospitalization was advocated for patients with decreasing percent of PTH >70%, who needed extra calcitriol supplement when POD1 PTH <1 pmol/L.

Preoperative vitamin D deficiency and postoperative hypocalcemia in thyroid cancer patients undergoing total thyroidectomy plus central compartment neck dissection

Background There appears to be a lack of consensus whether preoperative vitamin D deficiency (VDD) increases the risk of postoperative hypocalcemia and decreases the accuracy of postoperative parathyroid hormone (PTH) in predicting hypocalcemia in thyroid cancer patients undergoing total thyroidectomy (TT) plus central compartment neck dissection (CCND). This study aims to address these issues. Method All consecutive thyroid cancer patients who underwent TT plus CCND were retrospectively reviewed through a prospectively collected database between October 2015 and April 2016 in a tertiary referral hospital. The multivariate analysis was performed to identify the significant predictors for hypocalcemia. Receiver operator characteristic curve (ROC) was created and the area under the ROC was used to evaluate the predictive accuracy of postoperative PTH and compared between patients with or without VDD. Results A total of 186 patients were included. The incidence of VDD was 73.7% (137 patients). The incidence of biochemical and symptomatic hypocalcemia was similar in patients with or without VDD (P = 0.304 and 0.657, respectively). Multivariate analysis showed that only postoperative PTH was an independent predictor of symptomatic hypocalcemia (OR = 8.05, 95%CI = 3.99-16.22; P = 0.000). The area under the ROC was similar between patients with preoperative vitamin D level < 20 and ≥20 ng/mL (0.809 versus 0.845, P = 0.592). Conclusion VDD was not a significant risk factor for hypocalcemia following TT+CCND, and did not affect the accuracy of postoperative PTH as a predictor of postoperative hypocalcemia. Thus, routine preoperative screening for vitamin D seems to be unnecessary.BACKGROUND There appears to be a lack of consensus whether preoperative vitamin D deficiency (VDD) increases the risk of postoperative hypocalcemia and decreases the accuracy of postoperative parathyroid hormone (PTH) in predicting hypocalcemia in thyroid cancer patients undergoing total thyroidectomy (TT) plus central compartment neck dissection (CCND). This study aims to address these issues. METHOD All consecutive thyroid cancer patients who underwent TT plus CCND were retrospectively reviewed through a prospectively collected database between October 2015 and April 2016 in a tertiary referral hospital. The multivariate analysis was performed to identify the significant predictors for hypocalcemia. Receiver operator characteristic curve (ROC) was created and the area under the ROC was used to evaluate the predictive accuracy of postoperative PTH and compared between patients with or without VDD. RESULTS A total of 186 patients were included. The incidence of VDD was 73.7% (137 patients). The incidence of biochemical and symptomatic hypocalcemia was similar in patients with or without VDD (P = 0.304 and 0.657, respectively). Multivariate analysis showed that only postoperative PTH was an independent predictor of symptomatic hypocalcemia (OR = 8.05, 95%CI = 3.99-16.22; P = 0.000). The area under the ROC was similar between patients with preoperative vitamin D level < 20 and ≥20 ng/mL (0.809 versus 0.845, P = 0.592). CONCLUSION VDD was not a significant risk factor for hypocalcemia following TT+CCND, and did not affect the accuracy of postoperative PTH as a predictor of postoperative hypocalcemia. Thus, routine preoperative screening for vitamin D seems to be unnecessary.