Compartment Lymph Node Metastasis Research Articles

Intraoperative frozen section for determining the extent of surgery in papillary thyroid carcinoma: comprehensive risk factor assessment.

There is much debate on the optimal treatment approach of papillary thyroid carcinoma (PTC). Different guidelines base recommendations on various risk factors. While diagnosing the various risk factors is difficult due to the technical limitations, intraoperative frozen section (IFS) may be a feasible method. We aim to real-time evaluate the multiple risk factors, including lymph node metastasis (LNM), extrathyroidal extension (ETE), multifocality using IFS, and then identify a more effective surgical plan, which may help avoid the need for a second surgery and improve prognosis of patients. We retrospectively reviewed the medical records of 364 patients from January 1, 2021 to December 31, 2021. All the patients were initially recommended to undergo a hemithyroidectomy (HT) with isthmusectomy and ipsilateral central compartment neck dissection (CCND). IFS would be executed immediately. Further total thyroidectomies (TTs) would be performed if: (I) results of IFS showed >5 LNM, or (II) there are 1≤ LNM ≤5 but with ETE and/or multifocal carcinoma. The patients were divided and investigated according to the extent of surgery. Based on the results of IFS, 72 patients underwent TT. The TT group displayed larger average tumor diameter, greater age, higher average body mass index (BMI), and elevated incidence of hypertension and hyperlipidemia compared to the HT group. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of IFS were 77.61%, 100%, 100%, and 88.46%, respectively. IFS is a highly reliable procedure. Comprehensively evaluating central compartment LNM, ETE, and multifocal carcinoma through IFS helps identify a more reasonable surgical option under the current clinical consensus, which may thus help avoid the need for a second surgery.

Microbubble contrast agent SonoVue: An efficient medium for the preoperative lymphatic mapping of thyroid carcinoma.

Objective: To assess the value of microbubble contrast agent SonoVue in the thorough preoperative lymphatic mapping of patients with thyroid carcinoma, including the lymphatic drainage region, the detection of sentinel lymph node (SLN), and the diagnosis of lymph node metastasis (LNM). Materials and methods: 55 patients with 62 thyroid malignancies proved by surgical pathology (59 papillary thyroid carcinomas and three medullary thyroid carcinomas) who underwent preoperative lymphatic contrast-enhanced ultrasound (LCEUS) with microbubble contrast agent SonoVue were enrolled. All LNM were confirmed by pathology. The location of thyroid lesions, ultrasonic features of lymph nodes, lymphatic drainage region, and detection of SLN were assessed. The diagnostic performance (sensitivity, specificity, positive predictive value, negative predictive value and accuracy) of different parameters for the LNM diagnosis was calculated. Results: SonoVue effectively demonstrated the lymphatic drainage region for all enrolled thyroid carcinomas. The most common lymphatic drainage region for thyroid carcinomas was region VI (93.55%), followed by region III (62.90%), region IV (48.39%) and region II (4.84%). When divided by the lesion location, the most common lymphatic drainage regions for the nodule in isthmus, superior lobe and inferior lobe of the thyroid were region VI, region III, and region VI respectively. SLN was detected in 96.77% (60/62) of cases. The two cases without SLN demonstration had pathologically proven LNM. The most common sonographic sign of LNM was perfusion defect (54.17%). The diagnostic accuracy of SonoVue in central and lateral compartment LNM was 86.67% and 91.67%, respectively. Conclusion: Microbubble contrast agent SonoVue is a valuable imaging contrast medium for thorough preoperative lymphatic mapping in patients with thyroid carcinoma, including the lymphatic drainage region, the detection of SLN, and the diagnosis of LNM. LCEUS with SonoVue alone has limitations of false negatives when there is lymphatic vessel obstruction and may need to be combined with other ultrasound modalities.

Risk factor score for the prediction of central compartment lymph node metastasis in papillary thyroid carcinoma and its clinical significance.

To establish the criteria for a risk factor score (RFS) for predicting the probability of central compartment lymph node metastasis (LNM) in papillary thyroid carcinoma (PTC) and to explore the clinical significance of the RFS. The data of 412 patients with PTC who underwent surgical resection between May 2013 and July 2016 were retrospectively analysed and divided into two groups: a central LNM group and a non-central LNM group. In each group, the frequency of six risk factors was documented: sex, age, tumour size, extracapsular spread (ECS), tumour multifocality, and tumour location. The maximum likelihood method of discriminant analysis was adopted to calculate patient scores for the six risk indicators. In addition, the data of 104 patients with PTC admitted between July 2016 and December 2016 were prospectively analysed using this method and these six risk factors. A higher score represented one certain possibility that was the more appropriate for one patient. In the retrospective group, the result was as follows: 129 patients with positive (+) lymph nodes in the central compartment and 168 patients with negative (-) lymph nodes in the central compartment, which was in line with the actual results. In the prospective group, there were 28 patients with positive lymph nodes in the central compartment and 48 patients with negative lymph nodes in the central compartment. The coincidence rates using the RFS were 71.9% for the retrospective group and 73.1% for the prospective group. By simple and quantitative analyses of the presence of central LNM, the RFS is of great significance when choosing surgical approaches and postoperative individual-based treatment plans, as well as when determining the prognosis of central compartment LNM in patients with PTC.

The utility of sentinel Lymph node biopsy in the lateral neck in papillary thyroid carcinoma.

BackgroundRegional lymph node metastases (LNMs) are very common in papillary thyroid carcinoma (PTC) and associate with locoregional recurrence. The appropriate management of cervical lymph nodes is very important. Therefore, this study evaluated the application of sentinel lymph node biopsy (SLNB) in the lateral neck in PTC patients.MethodsThis prospective study was conducted from 1 November 2015 to 31 December 2017 and recruited 78 PTC patients treated with SLNB in the lateral neck and prophylactic lateral neck dissection (compartments II–IV) followed by thyroidectomy or lobectomy and central neck dissection.ResultsThere were 78 PTC patients enrolled and sentinel lymph nodes (SLNs) were detected among 77 patients. A total of 30 patients were diagnosed with SLN metastases (SLNMs). The remaining 47 patients were pathologically negative of SLN, whereas 4 patients were found with metastases in the non-SLN samples. The detection rate, sensitivity, specificity, and accuracy rate of SLNB in the lateral neck were 98.7%, 87.1%, 98.7%, and 93.6%, respectively. However, the values varied greatly in each specific compartment of the lateral neck, and all of them were no more than 80%. These 34 PTC patients diagnosed with lateral compartment LNM (LLNM) were more likely to be younger (41.38 vs. 48.95 years old, p = 0.002) and exhibit extrathyroidal extension (56.8% vs. 31.7%, p = 0.026) and central compartment LNM (66.7% vs. 12.1%, p < 0.001). Tumors located in the upper third of the thyroid lobe also had a significantly higher probability of LLNM compared with those in middle or inferior location (66.7% vs. 35.3% vs. 34.8%, p = 0.044). At last, age (OR=0.912, p = 0.026), tumor location (upper vs inferior, OR=17.478, p = 0.011), and central compartment LNM (OR=25.364, p < 0.001) were independently predictive of LLNM.ConclusionsSLNB can help surgeons to identify some PTC patients who may benefit from therapeutic lateral neck dissection and protect some patients from prophylactic lateral neck dissection. However, it cannot accurately indicate specific lateral compartment-oriented neck dissection. Meanwhile, LLNM is more likely to occur in PTC patients with younger age or upper pole tumors or central compartment LNM.

Ultrasound-based radiomics analysis for preoperative prediction of central and lateral cervical lymph node metastasis in papillary thyroid carcinoma: a multi-institutional study

BackgroundAn accurate preoperative assessment of cervical lymph node metastasis (LNM) is important for choosing an optimal therapeutic strategy for papillary thyroid carcinoma (PTC) patients. This study aimed to develop and validate two ultrasound (US) nomograms for the individual prediction of central and lateral compartment LNM in patients with PTC.MethodsA total of 720 PTC patients from 3 institutions were enrolled in this study. They were categorized into a primary cohort, an internal validation, and two external validation cohorts. Radiomics features were extracted from conventional US images. LASSO regression was used to select optimized features to construct the radiomics signature. Two nomograms integrating independent clinical variables and radiomics signature were established with multivariate logistic regression. The performance of the nomograms was assessed with regard to discrimination, calibration, and clinical usefulness.ResultsThe radiomics scores were significantly higher in patients with central/lateral LNM. A radiomics nomogram indicated good discrimination for central compartment LNM, with an area under the curve (AUC) of 0.875 in the training set, the corresponding value in the validation sets were 0.856, 0.870 and 0.870, respectively. Another nomogram for predicting lateral LNM also demonstrated good performance with an AUC of 0.938 and 0.905 in the training and internal validation cohorts, respectively. The AUC for the two external validation cohorts were 0.881 and 0.903, respectively. The clinical utility of the nomograms was confirmed by the decision curve analysis.ConclusionThe nomograms proposed here have favorable performance for preoperatively predicting cervical LNM, hold promise for optimizing the personalized treatment, and might greatly facilitate the decision-making in clinical practice.

Central Compartment Lymph Nodes Have Distinct Metastatic Patterns in Different Age Groups.

Background and PurposeCentral compartment lymph node metastasis (CLNM) is a manifestation of tumor aggressiveness and an indicator of tumor prognosis. The purpose of this study was to construct a nomogram for evaluating CLNM patterns in papillary thyroid carcinoma (PTC) in different age groups.MethodA total of 907 patients diagnosed with PTC from August 2014 to December 2018 were enrolled. A nomogram illustrating CLNM was generated using the results of multivariate logistic regression analysis.ResultsAccording to the best Youden index, we set the cut-off age at 45 years. Multivariate logistic regression analysis showed that in patients aged <45 years, large tumor size (P<0.05), extra-thyroid extension (P<0.05) and thyroglobulin level >40 ng/ml (OR=2.985, 95% CI 1.379-6.462; P<0.05) were independent risk factors; meanwhile, Hashimoto’s thyroiditis (OR=0.532, 95% CI 0.324-0.874; P<0.05) was a protective factor of CLNM. In the subgroup with age ≥45 years, large tumor size (P<0.05), extra-thyroid extension (P<0.05), unclear margin (OR=1.604, 95% CI 1.065-2.416; P<0.05), male gender (OR=2.009, 95% CI 1.257-3.212; P<0.05) were independent risk factors for CLNM. In the subgroup with age <45 years, an area under the curve (AUC) of 0.729 (95% CI 0.680-0.777); P<0.05) was obtained. In the ≥45 years subgroup, the AUC was 0.668 (95% CI 0.619-0.716; P<0.05).ConclusionCLNM of PTC in different age groups may have distinct patterns. Based on the potential risk factors for CLNM in patients with different age stratification, a user-friendly predictive model was established.

Clinical outcome of patients with differentiated thyroid cancer and raised antithyroglobulin antibody levels: a retrospective study

BackgroundThyroglobulin (Tg) is a specific tumor marker for differentiated thyroid cancer (DTC). However, in the presence of an antithyroglobulin antibody (TgAb), it becomes unreliable. The purpose of the study was to assess the long-term outcome of DTC patients with raised TgAb.MethodIn a retrospective study, we included patients with DTC who had raised TgAb following total thyroidectomy. We excluded patients with persistently raised Tg (≥ 1 ng/ml) or radioiodine avid disease. Serial TgAb levels, excellent response (ER), incomplete response (IR), and anatomical recurrence were evaluated.ResultsA total of seventy-six patients were included in the study. Patients with IR had higher baseline TgAb (1071.27 ± 1216.17 vs. 99.61 ± 91.29 IU/ml, p < 0.001) and central compartment lymph node metastases (70.8% vs. 46.4%, p = 0.035) in comparison to those in the ER group. In the first follow-up, 64 (84.2%) patients had a stable or fall in the TgAb (0 to − 98.3%). Sixty-eight patients received high-dose radioiodine therapy (RIT). Out of these, 59 (86.5%) had transient, and 51 (75%) had a long-term fall in TgAb. After a follow-up period of 58.74 ± 26.26 months, 63.2% (48 out of 76) patients had IR. Nine (11.8%) patients had a rising TgAb level (3.7–170.9%) from baseline. Eleven patients underwent 18F-FDG PET/CT, and five of them demonstrated metabolically active recurrent disease. Three patients underwent cervical lymph nodes dissection. None of the patients died during the follow-up period.ConclusionHigh post-operative TgAb levels and central compartment lymph nodal metastases are risk factors for IR. RIT leads to a significant fall in the TgAb in these patients. The low level of raised TgAb is associated with an excellent outcome. Patients with recurrences had very high baseline TgAb > 1000 IU/ml. Raised TgAb was associated with good clinical outcomes and not associated with increased mortality.

Clinicopathological Features as Prognostic Predictors of Poor Outcome in Papillary Thyroid Carcinoma.

Simple SummaryThyroid cancer incidence is increasing, with overdiagnosis being the major driver of the thyroid cancer “epidemic”. Papillary thyroid carcinoma, usually with excellent prognosis, sometimes has an aggressive metastatic pattern. This heterogeneity in progression makes it difficult to tailor treatment strategies for an individual patient. We aimed to identify clinicopathological factors associated with papillary thyroid carcinoma recurrence, persistence, and specific mortality. Our study supports that both pre-surgical factors, such as male gender, presence of psammoma bodies, gross extra-thyroidal extension, and lateral compartment lymph node metastases, as well as lymph vessel invasion, venous invasion, presence of necrosis, and incomplete surgical resection, should be taken into consideration regarding treatment and follow-up of PTC patients. The same is true when analysis is restricted to stage I patients. The importance of this report is to emphasize clinical and imaging pre-surgical thyroid cancer patients’ evaluation for an appropriate surgical treatment and patient prognosis.Papillary thyroid cancer (PTC) has an indolent nature and usually excellent prognosis. Some PTC clinicopathological features may contribute to the development of aggressive metastatic disease. In this work, we want to evaluate PTC clinicopathological features that are presurgical prognostic predictors of patients’ outcomes and find which indicators are more adequate for tailoring surgical procedures and follow-up. We studied a series of 241 PTC patients submitted to surgery. All patients’ files and histological tumor samples were reviewed. The 8th edition AJCC/UICC (American Joint Committee on Cancer/Union for International Cancer) Controlstaging system and the 2015 American Thyroid Association risk stratification system were used. Total thyroidectomy was performed in 228 patients, lymphadenectomy in 28 patients. Gross extrathyroidal extension (ETE) was present in 10 patients and 31 tumor resection margins were incomplete. Cervical lymph node metastases (LNMs) were present in 34 patients and distant metastases at diagnosis in four patients. In multivariate analysis, male gender (OR = 15.4, p = 0.015), venous invasion (OR = 16.7, p = 0.022), and lateral compartment LNM (OR = 26.7, p = 0.004) were predictors of mortality; psammoma bodies (PBs) (OR = 4.5, p = 0.008), lymph vessel invasion (OR = 6.9, p < 0.001), and gross ETE (OR = 16.1, p = 0.001) were predictors of structural disease status; male gender (OR = 2.9, p = 0.011), lymph vessel invasion (OR = 2.8, p = 0.006), and incomplete resection margins (OR = 4.6, p < 0.001) were predictors of recurrent/persistent disease. Our study supports that the factors helping to tailor patient’s surgery are male gender, presence of PBs, gross ETE, and lateral compartment LNM. Together with pathological factors, lymph vessel invasion, venous invasion, necrosis, and incomplete surgical resection, should be taken into consideration regarding treatment and follow-up of patients.

CUNR scoring system for the prediction of lateral lymph node metastasis in papillary thyroid carcinoma.

ObjectiveOur present study aimed to evaluate and compare the number and rate of central lymph node metastases (LNMs) for the prediction of lateral LNM (LLNM) in papillary thyroid carcinoma (PTC) and to develop a scoring system.ResultsCapsule invasion, tumor location in the upper portion of the thyroid, an ipsilateral central compartment LNM number ≥3, and an ipsilateral central compartment LNM rate of ≥56% were identified as significant independent predictors of ipsilateral lateral LNM in PTC. The predictive ability of an ipsilateral central compartment LNM rate ≥56% (area under the curve (AUC) = 0.802) was better than that of an ipsilateral central compartment LNM number ≥3 (AUC = 0.755). The ROC curves identified the best index point (CUNR) to distinguish the presence or absence of ipsilateral LLNM as 11, which has a high sensitivity (0.860) and a low false-negative rate (0.100, 1-Specificity). These findings were supported by the validation cohort.ConclusionsPatients with a CUNR index point equal to or greater than 11 and ipsilateral lateral lymph node dissection should be considered for a diagnosis of LLNM.Patients and MethodsA total of 1,281 PTC patients were included and divided into two groups: those with a presence of LLNM (n = 222) and those with an absence of LLNM (n = 1059). Univariate and multivariate analyses were performed to detect the risk factors for LLNM, and receiver operating characteristic (ROC) curves were used to detect the best cutoff values of these predictors. Additionally, a scoring system for the odds ratio (OR) of independent factors was developed and validated in an independent cohort of PTC patients (n = 560).

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

BackgroundAmong 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.MethodsIn 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.ResultsIn 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).ConclusionIntraoperative 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.

[Cervical lymph node metastasis in medullary thyroid carcinoma].

To study the patterns of cervical lymph node metastasis of medullary thyroid carcinoma. Ninety-one patients with medullary thyroid carcinoma first treated between January 1999 and October 2014 were analyzed retrospectively. Of 91 patients, 39 cases presented with clinical negative node (cN0) and 52 cases with clinical positive node (cN+). Central compartment dissection was performed in all cases. Lateral neck dissection was performed in 52 cN+ cases (71 sides). All neck dissection specimens were obtained and analyzed for lymph node (LN) involvement with respect to neck levels. The distribution of LN with metastasis was studied in cN+ patients and the following factors were used to study the predictive value of central compartment LN metastasis: sex, age, family history, tumor size, bilateral tumor, multifocality of the tumor, extracapsular spread, and remote metastasis. Univariate analysis with the χ(2) test was used to analyze the statistical correlation between central compartment LN metastasis and other clinical factors. Multiple logistic regression analysis was used to identify the factors related to central compartment metastasis. Neck and bilateral neck metastasis rates were 73.6%, 19.8% respectively. Metastasis rates in central compartment and superior mediastinal region were 68.1% and 27.5% respectively. The central compartment metastasis rate was 33.3% in cN0 patients and 94.2% in cN+ patients. The superior mediastinal metastasis rate was 2.6% in cN0 patients and 46.2% in cN+ patients. Extracapsular spread was an independent predictive factor for central compartment metastasis (χ(2)=15.592, P=0.000, OR=12.876). The incidences of LN metastases at level II, III, IV, V were 62.9%,84.5%,83.1%,50.0% in cN+ patient, respectively. Multi-sites were involved. The possibility of lateral neck metastasis was higher when preoperative value of calcitonin was higher than 300 ng/L (66.7% vs 28.6%, χ(2)=5.771, P=0.016). Cervical lymph node metastasis of medullary thyroid carcinoma is higher. Central compartment dissection is necessary in cN0 patients with extracapsular spread. Neck dissection from level II to level VII was necessary in cN+ patients. Preoperative value of calcitonin maybe can predict the lateral neck metastasis incidence.

Prediction of central compartment lymph node metastasis in papillary thyroid microcarcinoma

We aimed to determine the predictive factors for central compartment lymph node metastasis (LNM) in papillary thyroid microcarcinoma (PTMC). We undertook a retrospective study of 291 patients treated for PTMC. The following criteria were assessed to predict the presence of central compartment LNM: sex, age, tumour multifocality, tumour size, tumour bilaterality, extracapsular spread (ECS), lateral neck LNM, coexistence of chronic lymphocytic thyroiditis, BRAF(V) (600E) mutation and ultrasonography (US) features. Univariate and multivariate analyses were performed to identify clinicopathological characteristics and US findings in predicting central compartment LNM from PTMC. The central compartment LNM affected 133 (45.7%) of 291 patients. With use of univariate and multivariate analyses, male gender (OR 2.020; P = 0.039), tumour size (>5 mm) (OR 3.687; P = 0.015), ESC (OR 2.330; P = 0.044), lateral LNM (OR 15.075; P = 0.000) and BRAF(V) (600E) mutation (OR 2.464; P = 0.000) were independently correlated with central compartment LNM. Age, tumour multifocality, tumour bilaterality, coexistence of chronic lymphocytic thyroiditis and US characteristics were not significantly related to the presence of central compartment LNM. We have also developed a nomogram to predict the probability of central compartment LNM for an individual patient. The sensitivity was 71.9% and specificity was 70.3%, with an under the receiver operating characteristic (ROC) curve of 0.772. A prophylactic neck dissection of the central compartment should be considered particularly in PTMC patients with male gender, a >5 mm tumour size, ECS of the tumours, lateral LNM and positive BRAF(V) (600E) mutation.

Incidence and clinical characteristics of prelaryngeal lymph node metastasis in papillary thyroid cancer

There is little data that determine the clinical characteristics of prelaryngeal lymph nodes (PLN) metastasis in patients with papillary thyroid cancer (PTC). The aims of this prospective study were to evaluate the incidence and the clinical characteristics of metastasis to the PLN for PTC patients who underwent total thyroidectomy and prophylactic central neck dissection. Sixty-seven patients who underwent total thyroidectomy and prophylactic bilateral central lymph node neck dissection for PTC were enrolled. Central neck compartment was further divided into prelaryngeal, ipsilateral/contralateral paratracheal, and pretracheal regions. Clinicopathologic factors including age, sex, tumor size and location, extrathyroidal extension, and central and lateral nodal metastasis were evaluated. Of the 67 patients who underwent PLN dissection, 13 (19.4 %) had evidence of PLN metastasis. Tumor size was significantly larger in patients with PLN involvement (2.28 versus 1.12 cm; p = 0.020). Additionally, primary tumors larger than 1 cm, extrathyroidal extension, and isthmus involvement were more prevalent in PLN-positive patients. Patients with positive PLNs were also more frequently found to have lateral lymph node metastasis (23.1 vs. 1.9 %; p = 0.021), pretracheal lymph node metastasis (76.9 vs. 27.8 %; p = 0.003), and bilateral central lymph node metastasis (38.5 vs. 11.1 %; p = 0.031) than PTC patients without PLN involvement. The incidence of PLN metastasis in PTC patients who underwent prophylactic central lymph node neck dissection was 19.4 %. PLN metastasis was associated with tumor size, extrathyroidal extension, isthmus involvement, and other compartment lymph node metastasis.

The usefulness and accuracy of sentinel lymph node biopsy using single photon emission computed tomography/computed tomography with 99mTc phytate to detect locoregional lymph node metastases in patients with papillary thyroid carcinoma

PurposeRegional lymph node (LN) metastases are detected in 57-85% of patients with papillary thyroid carcinoma (PTC) and are associated with increased tumor recurrence. However, the management of lymphatic disease in patients with PTC has been ongoing source of debate. We have prospectively assessed the usefulness and accuracy of sentinel LN (SLN) biopsy for the detection of LN metastases in patients with PTC on preoperative imaging using single photon emission computed tomography/computed tomography (SPECT/CT) and 99mTc phytate.MethodsWe prospectively assessed 39 patients with PTC who had risk factors for recurrence or with the necessity of intraoperative LN sampling for suspicious LN metastases on preoperative imaging from August 2010 to March 2011. The patients underwent preoperative lymphoscintigraphy and SPETC/CT and intraoperative SLN biopsy (SLNB).Results99mTc lymphoscintigraphy and SPECT/CT localized SLN in 38 patients (97.4%), with the gamma probe identifying 2.15 mean SLNs in the lateral neck of the 39 patients. Skip metastasis was found in one patient, and lateral compartment LN metastasis in 17 (43.5%). The sensitivity, specificity, and accuracy of SLNB for lateral compartment LN metastasis were 88.2%, 100%, and 94.8%, respectively. SLNB was more accurate and useful for lateral than for central compartment LN metastasis.ConclusionSPECT/CT improved SLN detection and anatomical localization compared with lymphoscintigraphy. SLNB in patients with risk factors for recurrence or the necessity of intraoperative LN sampling for suspected LN metastases on preoperative imaging was accurate in detecting LN metastases and may help in deciding whether to perform lateral compartment dissection in patients with PTC.

Predictive Factors for Central Compartment Lymph Node Metastasis in Thyroid Papillary Microcarcinoma

We examined the incidence of nodal involvement and attempted to determine the predictive factors for central compartment lymph node (LN) metastasis in thyroid papillary microcarcinoma (PMC). Retrospective chart review. We undertook a retrospective study of 52 patients treated between January 2000 and December 2005 for PMC by total thyroidectomy and elective central compartment LN dissection with or without comprehensive lateral neck dissection (n = 9). There were 45 women and 7 men whose mean age was 47.6 +/- 11.5 years. The following criteria were used to study the predictive value of central compartment LN metastasis: sex, age, multifocality of the tumor, extracapsular spread (ECS), the involvement of the lateral neck LN, tumor size, and tumor location. In 16 of 52 (31%) patients, central compartment LN metastasis was found. With use of univariate and multivariate analysis, ECS, lateral LN metastasis, and tumor size (>5 mm) were independent correlates of central compartment metastasis. Sex, age, multifocality, and tumor location were not associated with central compartment LN metastasis and did not significantly influence the predictive value of these variables. We found a significant association among ECS, lateral LN metastasis, tumor size (>5 mm), and central compartment LN metastasis in patients with PMC. A prophylactic neck dissection of the central compartment should be considered particularly in patients with ECS of the tumors, metastatic LN in the lateral neck, and a greater than 5 mm tumor size.