Routine bilateral central lymph node clearance for papillary thyroid cancer

Risk factors and clinical indication of metastasis to lymph nodes posterior to right recurrent laryngeal nerve in papillary thyroid carcinoma: a single-center study in China

BACKGROUND

Lymph nodes posterior to right recurrent laryngeal nerve (PRRLN) may be frequently overlooked during central compartment dissection (CCD) for papillary thyroid carcinoma (PTC). The purpose of this study was to investigate risk factors of lymph node PRRLN metastasis in right-sided PTC, thereby to identify the indications for lymph node PRRLN dissection.

METHODS

We conducted a retrospective study of patients with right-sided PTC who underwent a thyroidectomy plus lymph node PRRLN dissection during ipsilateral CCD.

RESULTS

Overall, 108 patients (26.7%) had lymph node PRRLN metastases, including 26 (6.4%) who presented with solely lymph node PRRLN positivity. Factors of extrathyroidal extension, multifocality, larger tumor (≥1 cm), level VIa positivity (p < .0001 for each), and lateral compartments positivity (p = .0002) significantly predicted lymph node PRRLN metastasis in right-sided PTC.

CONCLUSION

Lymph node PRRLN should be routinely explored during CCD because of the possibility of only involvement in PTC. Factors of tumors larger than 1 cm, multifocality, and extrathyroidal extension were independent predictors of lymph node PRRLN metastasis in right-sided PTC, and suggested the clinical indications of lymph node PRRLN dissection.

Total thyroidectomy, without prophylactic central lymph node dissection, in the treatment of differentiated thyroid cancer. Clinical retrospective study on 221 cases

Total thyroidectomy (TT) is the standard of care for differentiated thyroid cancer (DTC), but still there is no consensus about the role of routine use of prophylactic central lymph node dissection. The aim of this study was to analyze our results of TT without prophylactic central lymphadenectomy in the treatment of DTC. Clinical records, between January 1998 and December 2005, of 221 patients undergoing TT, without prophylactic central lymph node dissection, were retrospectively evaluated. Two hundred and eleven patients (95.47 %) also underwent radioiodine (RAI) ablation followed by thyroid stimulating hormone (TSH) suppression therapy. In patients with loco-regional lymph nodal recurrence, lateral and central lymph node dissection was performed. The incidence of permanent hypoparathyroidism (iPTH <10 pg/ml) and permanent vocal fold paralysis were, respectively, 0.91 and 0.91 %. After a 9.6 ± 3.5 years mean follow-up, the rate of loco-regional recurrence, with positive cervical lymph nodes, was 3.16 % (7/221 patients). In these cases a lateral and central lymphadenectomy was carried out without significant complications. Our results showed that TT without prophylactic central lymph node dissection, followed by RAI ablation, was associated with low morbidity and low loco-regional recurrence rate, even if the lack of a control group treated with TT plus prophylactic central lymphadenectomy suggests caution against generalization of our assumption. Such last combined procedure could be indicated in high-risk patients, in whom loco-regional recurrence is more frequent. However, given the trend in the literature toward prophylactic lymphadenectomy and the avoidance of RAI treatment, prospective randomized trials should be conducted to better clarify this issue.

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.

A systematic review and meta-analysis of prophylactic central neck dissection on short-term locoregional recurrence in papillary thyroid carcinoma after total thyroidectomy

BACKGROUND

Prophylactic central neck dissection (pCND) at the time of total thyroidectomy (TT) remains controversial in clinically node-negative (cN0) papillary thyroid carcinoma (PTC). Despite occult central lymph node metastases being common, it is unclear if removing these metastases initially would reduce future locoregional recurrence (LRR). This systematic review and meta-analysis aimed at comparing the short-term LRR between patients who underwent TT with pCND and those who underwent TT alone.

METHODS

A systematic review of the literature was performed to identify studies comparing LRR between patients with PTC who underwent TT + pCND (group A) and those who underwent TT alone (group B). Inclusion criteria were cN0 patients, with each comparative group containing > 10 patients, and with the number of LRR and mean follow-up duration available. The pooled incidence rate ratio (IRR) was used for calculating the LRR rate between the two groups. Other parameters evaluated included postoperative radioiodine (RAI) ablation, surgically related complications, and overall morbidity. Meta-analysis was performed using a fixed-effects model.

RESULTS

Fourteen studies matched the selection criteria. Of the 3331 patients, 1592 (47.8%) belonged to group A, while 1739 (52.2%) belonged to group B. Relative to group B, group A was significantly more likely to have postoperative RAI ablation (71.7% vs. 53.1%; odds ratio [OR] = 2.60 [95% confidence interval (CI) = 2.12-3.18]), temporary hypocalcemia (26.0% vs. 10.8%; OR = 2.56 [CI = 2.04-3.21]), and overall morbidity (33.2% vs. 17.7%; OR = 2.12 [CI = 1.75-2.57]). When temporary hypocalcemia was excluded, overall morbidity was similar between the two groups (7.3% vs. 6.8%; OR = 1.07 [CI = 0.78-1.47]). Group A had a significantly lower risk of LRR than group B (4.7% vs. 8.6%; IRR = 0.65 [CI = 0.48-0.86]).

CONCLUSIONS

Group A was more likely to have postoperative RAI ablation, temporary hypocalcemia, and overall morbidity than group B. Temporary hypocalcemia was the major surgical morbidity in pCND and, when excluded, the overall morbidity appeared similar between the two groups. Although our meta-analysis would suggest that those who undergo TT + pCND may have a 35% reduction in risk of LRR than those who undergo TT alone in the short term (< 5 years), it remains unclear how much of this risk reduction is related to increased use of RAI ablation and potential selection bias in some of the studies examined.

Number of central lymph node metastasis for predicting lateral lymph node metastasis in papillary thyroid microcarcinoma

BACKGROUND

The purpose of this study was to present our evaluation of the relationship between the number of positive central lymph nodes and lateral lymph node metastasis in patients with papillary thyroid microcarcinoma (PTMC).

METHODS

Up to 141 patients with PTMC were divided into 3 groups according to different positive central lymph node classifications as follows: group A, no positive central lymph node; group B, 1 positive central lymph node; and group C, 2 or more positive central lymph nodes.

RESULTS

Incidence of lateral lymph node metastasis was 30.5% (43 of 141). It was significantly high in group C compared with groups A and B, although there was no significant difference between groups A and B. Number of positive central lymph node ≥2, underlying Hashimoto thyroiditis, and extrathyroidal extension were the independent predictive factors for lateral lymph node metastasis on multivariate analysis.

CONCLUSION

Lateral lymph node metastasis was mainly observed in patients with ≥2 positive central lymph nodes, which is an independent predictive factor for lateral lymph node metastasis. Therefore, ≥2 positive central lymph nodes may be valuable in predicting lateral lymph node metastasis.

Clinical analysis of prophylactic central neck dissection for papillary thyroid carcinoma

Purpose

The need of prophylactic central neck dissection (PCND) in patients with papillary thyroid carcinoma (PTC) is still controversial. The major restriction of PCND is the potential complications. We undertook a retrospective study to discuss its necessity in PTC patients.

Methods

A total of 188 patients with PTC who underwent total thyroidectomy and PCND were involved. In all of these, central lymph nodes were pathologic examined. Univariate and multivariate analyses were performed based on tumor location and size, etc.

Results

Overall, node metastases were found in 44.1 % (83/188) of patients. Tumor size was the independent positive predictor for lymph node metastasis, while gender, age, tumor multifocality, tumor location, and capsular infiltration were not independent predictors of central lymph node metastases. Postoperative complications happened in 5.3 % (10/188) of patients, which 4.8 % (9/188) had temporary hypocalcemia and 0 % (0/188) had permanent hypocalcemia. Rates of temporary and permanent recurrent laryngeal nerve injury were 0.5 % (1/188) and 0 % (0/188), respectively.

Conclusions

PCND is recommended in all patients with PTC.

German Association of Endocrine Surgeons practice guideline for the surgical management of malignant thyroid tumors

INTRODUCTION

Over the past years, the incidence of thyroid cancer has surged not only in Germany but also in other countries of the Western hemisphere. This surge was first and foremost due to an increase of prognostically favorable ("low risk") papillary thyroid microcarcinomas, for which limited surgical procedures are often sufficient without loss of oncological benefit. These developments called for an update of the previous practice guideline to detail the surgical treatment options that are available for the various disease entities and tumor stages.

METHODS

The present German Association of Endocrine Surgeons practice guideline was developed on the basis of clinical evidence considering current national and international treatment recommendations through a formal expert consensus process in collaboration with the German Societies of General and Visceral Surgery, Endocrinology, Nuclear Medicine, Pathology, Radiooncology, Oncological Hematology, and a German thyroid cancer patient support organization.

RESULTS

The practice guideline for the surgical management of malignant thyroid tumors includes recommendations regarding preoperative workup; classification of locoregional nodes and terminology of surgical procedures; frequency, clinical, and histopathological features of occult and clinically apparent papillary, follicular, poorly differentiated, undifferentiated, and sporadic and hereditary medullary thyroid cancers, thyroid lymphoma and thyroid metastases from primaries outside the thyroid gland; extent of thyroidectomy; extent of lymph node dissection; aerodigestive tract resection; postoperative follow-up and surgery for recurrence and distant metastases.

CONCLUSION

These evidence-based recommendations for surgical therapy reflect various "treatment corridors" that are best discussed within multidisciplinary teams and the patient considering tumor type, stage, progression, and inherent surgical risk.

Surgical extent of central lymph node dissection in clinically node-negative papillary thyroid cancer

BACKGROUND

The indications for elective bilateral central node dissection for patients with unilateral papillary thyroid carcinoma (PTC) who are clinically node negative are still not verified. We investigated the predictive factors of lymph node metastasis and formulated guidelines for surgical extent.

METHODS

From 2004 to 2009, 325 patients diagnosed with unilateral PTC who had undergone total thyroidectomy with bilateral central lymph node dissection (CLND) were enrolled retrospectively.

RESULTS

Central node metastasis was found in 45.2%, ipsilateral and contralateral lymph node metastasis was found in 40.0% and 16.0%, respectively. Tumor size larger than 1.0 cm and extrathyroidal extension were significant factors in predicting ipsilateral node metastasis (p = .004, < .001, respectively), and extrathyroidal extension and ipsilateral lymph node metastasis predicted contralateral node metastasis in multivariable analysis (p = .039, < .001, respectively).

CONCLUSION

Elective bilateral central node dissection may be considered in unilateral PTC with extrathyroidal extension or ipsilateral node metastasis.

Experience and analysis of Delphian lymph node metastasis in patients with papillary thyroid carcinoma

Background

Recently, lymph node metastasis (LNM) has been regarded as an important factor influencing loco-regional recurrence and survival rate in papillary thyroid cancer (PTC) patients. The aims of this study were to investigate the detection rate and metastasis rate of the Delphian lymph node (DLN) and clinical patterns related to regional LNM, and to examine how DLN metastasis affects PTC treatment.

Methods

We reviewed the medical records of 413 patients with pathologically confirmed PTC from among 452 patients who underwent thyroid surgery between January 2010 and October 2010 in the Department of Endocrine Surgery at Kosin University Gospel Hospital in Busan, South Korea.

Results

Multivariate analyses revealed a significantly higher proportion of cases with lymphovascular invasion (56.6% vs. 12.5%, P <0.001), central neck node metastasis (88.6% vs. 34.5%, P <0.001) and lateral neck node metastasis (47.2% vs. 10.2%, P <0.005) among cases with DLN metastasis compared to those without. The negative predictive value (NPV) of DLN metastasis with regard to the presence of contralateral central LNM for cases with a tumor size 1 cm or smaller than 1 cm was found to be 93.3% (127/136).

Conclusion

When DLN metastasis is not detected in papillary thyroid microcarcinomas (PTMC), thyroid lobectomy on the affected side and ipsilateral central neck lymph node dissection should be sufficient. In addition, even in cases where lateral neck LNM is not detected on preoperative examination, if DLN metastasis is detected postoperatively, more careful attention should be paid to the lateral neck nodes during follow-up.

Management of well-differentiated thyroid cancer

This review provides an overview of current guideline recommendations for the clinical evaluation and surgical management of well-differentiated thyroid cancer, and further examines the evidence for controversial topics such as the minimum degree of primary resection, the role of elective central neck dissection, and the extent of lateral neck dissection. Well-differentiated thyroid cancer comprises the majority of thyroid cancers, about 90%, and includes both papillary and follicular carcinomas. Despite convergence of the medical community in establishing treatment guidelines under the American Thyroid Association, there still remain many areas of disagreement.

Lateral cervical lymph node metastases in papillary thyroid cancer: a systematic review of imaging-guided and prophylactic removal of the lateral compartment

BACKGROUND

Papillary thyroid cancer (PTC) is a common endocrine cancer and frequently presents with lymph node (LN) metastases. The frequency of LN metastases in the lateral compartment and their surgical removal are poorly defined. There are no prospective randomised controlled trials addressing an eventual outcome difference relating to the extent of the initial surgical approach. The aim of this study was to define the extent of lateral LN involvement and the role of imaging in identification of these metastatic LN.

DESIGN AND METHODS

A systematic review of studies of patients with PTC undergoing either prophylactic or therapeutic lymphadenectomy of the lateral cervical compartment. Studies involving imaging modalities in the detection of lateral cervical LNs in PTC were also analysed.

RESULTS

Systematic review on the frequency of lateral LN metastases and their detection using various imaging tools identified 19 studies containing data on 5587 patients undergoing prophylactic or imaging-guided removal of the lateral compartment. Imaging-guided surgery retrieved cancerous lateral LNs in 446/3178 or 14% of eligible patients, whilst prophylactic lateral neck dissection yielded histopathological proof of cancer in 1177/204 or 57·5% of patients. The frequency of lateral compartment metastases increased with T stage. The sensitivity of ultrasound and CT was poor as low as 27% when accurately calculated.

CONCLUSION

Metastatic cervical LNs were found in more than half of patients when prophylactic lateral LN dissection was performed. Use of conventional imaging for the selection of the surgical approach to the lateral cervical compartment may commonly identify stage N1a instead of N1b and thus lead to false stage assignment as stage III rather than stage IV, concealing the severe prognostic implications of this stage progression in individual patients.

Ipsilateral and contralateral central lymph node metastasis in papillary thyroid cancer: patterns and predictive factors of nodal metastasis

BACKGROUND

The aims of this study were to evaluate the rate and risk factors of ipsilateral and contralateral central lymph node (CLN) metastases in patients with papillary thyroid cancer (PTC).

METHODS

A total of 161 patients who underwent total thyroidectomy with prophylactic CLN dissection (CLND) to treat PTC were enrolled.

RESULTS

Of 134 total cases excluding tumors located in the isthmus and bilateral lobes, 72 cases (53.7%) involved CLN metastases. Tumor size, age, and sex were found to be predictive of ipsilateral CLN metastasis and the rate of ipsilateral CLN metastasis in tumors > 1 cm was 59.6%. Contralateral CLN metastases were more prevalent only in tumors that already had ipsilateral CLN metastases (27.3%, p = .002).

CONCLUSIONS

It is suggested that risk factors of ipsilateral and contralateral CLN metastases should be considered while planning the extent of CLND in patients with clinically node-negative and unilateral PTC upon preoperative ultrasonography.

Utility of surgeon-performed ultrasound assessment of the lateral neck for metastatic papillary thyroid cancer

Ultrasound is the recommended staging modality for papillary thyroid cancer. Surgeons proficient in US assessment of the neck and experienced in the management of papillary thyroid cancer (PTC) appear uniquely qualified to assess the lateral cervical lymph nodes for metastatic disease. Of 310 patients treated for PTC between 2000 and 2008, 109 underwent surgeon-performed ultrasound (SUS) of the lateral neck preoperatively. Fine needle aspiration was performed on suspicious lateral lymph nodes. SUS findings were compared with FNA cytology and results of postoperative imaging studies. The sensitivity and negative predictive value of SUS were 88% and 97%, respectively. Four patients were found to have missed metastatic disease within 6 months. No patient underwent a nontherapeutic neck dissection. SUS combined with US-guided FNA of suspicious lymph nodes can accurately stage PTC to reliably direct surgical management.

Central cervical lymph node metastases in papillary thyroid cancer: a systematic review of imaging-guided and prophylactic removal of the central compartment

BACKGROUND

Papillary thyroid cancer (PTC) is a common endocrine cancer and commonly presents with lymph node (LN) metastases. The role of surgical removal of the central cervical LN compartment is poorly defined. There are no prospective randomized controlled trials addressing the relevance to the extent of the initial surgical approach.

DESIGN AND METHODS

A systematic review of studies of patients with PTC undergoing either prophylactic or therapeutic lymphadenectomy of the central LNs was carried out. Studies involving imaging modalities in the detection of LNs in PTC were also analysed.

RESULTS

Twenty-one studies contained data on 4188 patients undergoing prophylactic or imaging-guided removal of the central compartment. Imaging-guided surgery retrieved cancerous central LNs in 346 or 30% of eligible patients, whilst prophylactic central neck dissection yielded histopathological proof of cancer in 898 or 26·2% of patients. Five imaging studies revealed data on the use of ultrasound (US) and/or computerized tomography (CT). The sensitivity of US and CT was poor, ranging from 50% to 70% when accurately calculated.

CONCLUSION

Metastatic central LNs are found in nearly half of all patients with PTC when prophylactic central lymph node dissection (CLND) is performed. With unreliable imaging modalities, prophylactic CLND should be performed on all patients with PTC.

Patterns of lymph node metastases in papillary thyroid carcinoma: results from consecutive bilateral cervical lymph node dissection

BACKGROUND

In patients with papillary thyroid carcinoma (PTC), the appropriate extent of lymph node dissection has not yet been established due to lack of accurate patterns of lymph node metastases (LNM). The aim of this study was to clarify the LNM pattern in PTC patients based on our institution's experience with a consistent technique of bilateral neck dissection, and to consider the rational extent of lymph node dissection.

METHODS

Between 1990 and 1999, 152 consecutive patients with PTC who underwent curative total thyroidectomy and bilateral neck dissection as initial treatment were analyzed. The patterns of LNM according to clinicopathological classification were analyzed using the lymph node ratio (LNR; number of metastatic lymph nodes/number of dissected nodes) and frequency (FLNM; number of patients with LNM/number of dissected patients) in cervical compartments.

RESULTS

Regardless of clinicopathological classification, LNR in the central compartment was consistently higher than in other compartments, and FLNM in the ipsilateral lateral compartment was consistently higher than in other compartments except for multifocal tumors. The LNR and FLNM in the contralateral lateral compartment were significantly higher in advanced (≥T3) cases than in cases with smaller tumors (T1) and were comparable to those in the ipsilateral lateral compartment in advanced (≥T3) cases.

CONCLUSIONS

The pattern of LNR provided a better reflection of the patterns of LNM. In terms of the LNR, central neck dissection is the basic extent of lymph node dissection for all clinically apparent PTC. In advanced patients, it is also advisable to include bilateral lateral neck dissection.

Pattern and risk factors of central compartment lymph node metastasis in papillary thyroid cancer: a prospective study from an endocrine surgery centre

Lymphatic metastasis in papillary thyroid cancer (PTC) is eminent; however, the extent of central compartment lymph nodes dissection (CCD) is controversial and requires the knowledge of pattern and risk factors for central compartment lymph nodes metastasis (CCM). We did a prospective study of 47 cases with PTC who underwent total thyroidectomy (TT) with CCD with/without lateral lymph nodes dissection (LND). Clinicopathological profile including CCM as ipsilateral and contralateral was documented. On histopathology, the mean tumour size was 3.57 ± 2.42 cm 59.6% had CCM, which was bilateral in the majority (60.72%). The tumour-size was the most important predictor for lymph nodes metastasis-(P=0.018) whereas multicentricity-(P=0.002) and ipsilateral CCM-(P=0.001) were the predictors for contralateral CCM. The long-term morbidity of CCD done in primary setting is comparable with TT-alone. Bilateral CCD should be done with thyroidectomy in PTC, otherwise the risk of residual diseases and subsequent recurrence is high. The long-term morbidity is comparable in experienced hands.

The role of prophylactic central neck dissection in differentiated thyroid carcinoma: issues and controversies

Prophylactic central neck dissection (pCND) in differentiated thyroid carcinoma (DTC) is one of the most controversial surgical subjects in recent times. To date, there is little evidence to support the practice of pCND in patients with DTC undergoing total thyroidectomy. Although the recently revised American Thyroid Association (ATA) guideline has clarified many inconsistencies regarding pCND and has recommended pCND in “high-risk” patients, many issues and controversies surrounding the subject of pCND in DTC remain. The recent literature has revealed an insignificant trend toward lower recurrence rate in patients with DTC who undergo total thyroidectomy and pCND than those who undergo total thyroidectomy alone. However, this was subjected to biases, and there are concerns whether pCND should be performed by all surgeons who manage DTC because of increased surgical morbodity. Performing a unilateral pCND may be better than a bilateral pCND given its lower surgical morbidity. Further studies in this controversial subject are much needed.

Well-differentiated thyroid carcinomas: management of the central lymph node compartment and emerging biochemical markers

Well-differentiated thyroid cancers (WDTCs) are generally indolent cancers that are associated with a low mortality. Although the incidence of these tumors is increasing, there has not been an associated increase in the mortality rates. As we gain a greater understanding and more experience with these good prognosis cancers, the way in which we treat these tumors is evolving. The definition of persistent or recurrent disease has seen a shift from being a clinical and/or radiological diagnosis to now one based on a biochemical blood marker, thyroglobulin. Central lymph node metastases are a very common problem in WDTC, being present in up to 90% of patients. The optimal surgical management of the central lymph node compartment remains a hotly debated topic. This paper identifies these controversies and presents available data surrounding these issues. Biochemical tumor markers are gaining wider use in practice and in time hopefully provide more specific information with which surgical decision-making can be based. A summary of the clinically available markers is presented.

Analysis of prognostic factors in patients with multiple recurrences of papillary thyroid carcinoma

PURPOSE

Numerous studies in the past have mentioned various factors that influence the recurrence of papillary thyroid carcinoma, including age, tumor size, advanced stage, extrathyroidal extension, and distant metastasis, and attempts have been made to classify the disease into low-risk and high-risk group based on these clinicopathological factors. However, there has been relatively scarce study on patients with multiple recurrent papillary thyroid carcinoma. This study analyzed the risk factors associated with such cases.

MATERIALS AND METHODS

This study investigated various clinicopathological factors of 416 patients who were diagnosed with papillary thyroid carcinoma and received primary surgery at Yonsei University Wonju College of Medicine, Department of Surgery, from January 1983 to December 2006 and were followed up until October 2010. An investigation of factors associated with patients showing multiple recurrences was made.

RESULTS

Patients were divided into 3 groups: group 1 (no recurrence, n=380), group 2 (1 recurrence only, n=21), and group 3 (multiple recurrences, n=15). The univariate analysis on risk factors revealed tumor size greater than 2 cm, multifocality, clinical apparent lymph node metastasis to be risk factors associated with multiple recurrences of papillary thyroid carcinoma. A multivariate analysis performed on variables selected from univariate analysis demonstrated no significant risk factor. The 10-year disease-specific survival for 3 different patient groups (group 1, 2, and 3) was 100%, 100%, and 83.1%, respectively, and patients in more clinically advanced group demonstrated poorer prognosis (p<0.001). The 10-year overall survival rate for the 3 patient groups was 93.9%, 100%, and 92%, respectively, and clinically advanced groups tended to show poorer overall survival rate as well (p=0.046).

DISCUSSION

A more aggressive and extensive surgery, as well as closer follow up, is to be required when operating on patients with tumor size greater than 2 cm, multifocality, clinical apparent lymph node metastasis. The use of imaging modalities, such as ultrasonography and PET-CT scan, may be desirable when monitoring such patients.

Performing contralateral central lymph node dissection in papillary thyroid carcinoma: a decision approach

BACKGROUND

Substantial controversy exists over the role of prophylactic neck dissection for patients with papillary thyroid carcinoma (PTC). We hypothesized that a therapeutic strategy of performing a routine intraoperative frozen section of the ipsilateral central lymph node (CLN) after elective ipsilateral CLN dissection (CLND) for all unilateral PTC and then performing a contralateral CLND if the frozen section is positive for malignancy would reduce morbidity compared to a therapeutic strategy of routine bilateral CLND.

METHODS

In a group of 419 patients with PTC undergoing thyroidectomy during study the period, the 203 patients who had unilateral PTC and no evidence of adenopathy on ultrasonography were prospectively enrolled in our nonrandomized study that was performed between March 2009 and February 2010. Patients underwent a total thyroidectomy if tumor size was over 1 cm or extrathyroidal was detected on ultrasonography. Patients underwent a subtotal or near-total thyroidectomy if tumor size was <1 cm and additional benign tumor existed on contralateral lobe. There were 25 patients who had a unilateral CLND with a subtotal or near-total thyroidectomy, and 178 patients who underwent a unilateral or bilateral CLND with a total thyroidectomy.

RESULTS

There was no difference in the rate of major complications between unilateral CLND group and bilateral CLND group. The rate of transient hypocalcemia was 31.8% in the unilateral CLND group and 45.7% in the bilateral CLND group (p = 0.084). The rate of voice change was 7.6% in the unilateral CLND group 4.3% in the bilateral CLND group (p = 0.438). The ratio of malignant to all nodes retrieved was 0.5/7.88 in the unilateral CLND group and 5.13/17.20 in the bilateral CLND group. There was 78.3% sensitivity and 100% specificity for frozen biopsy of ipsilateral CLN to predict contralateral CLN metastasis. A positive ipsilateral CLN frozen biopsy was significantly associated with contralateral CLN metastasis (p < 0.001), as was younger age (p = 0.002) and existence of extrathyroidal extension (p = 0.031), each on univariate analysis.

CONCLUSIONS

In patients with unilateral PTC, routine ipsilateral CLND with intraoperative reading of the frozen section can be employed to assess the risk of contralateral CLN metastasis. This information should be of value in deciding whether to perform contralateral CLND or not.

Preoperative BRAF Mutation Has Different Predictive Values for Lymph Node Metastasis according to Tumor Size

Objective. To investigate whether BRAF mutation of papillary thyroid carcinoma (PTC) has different predictive values for regional lymph node (LN) metastasis according to tumor size.

Study Design. Prospective cohort study.

Setting. A tertiary hospital.

Subjects and Methods. From January 2009 to August 2009, the authors prospectively enrolled 102 consecutive patients with unifocal PTC based on the findings of ultrasonography-guided fine-needle aspiration biopsy (FNAB). BRAF mutation was tested on preoperative FNAB specimens. Total thyroidectomy and bilateral central neck dissection (± lateral neck dissection) was performed for all patients. Among 102 patients, 71 who were confirmed to have unifocal PTC by the surgical pathology were finally selected. The 71 patients were classified into 3 groups according to their tumor size: group I, ≤0.5 cm; group II, >0.5 cm and ≤1 cm; and group III, >1 cm. LN metastasis was evaluated in the surgical specimen as a dependent variable. The authors investigated whether BRAF mutation is predictive of LN metastasis in each group.

Results. Overall, BRAF mutation was a significant predictor of LN metastasis ( P = .045). When patients were classified into 3 groups, frequency of LN metastasis increased with tumor size: 4.8%, 50.0%, and 66.7% ( P < .001). However, the frequency of BRAF mutation was not different among 3 groups: 61.9%, 56.3%, and 72.2% ( P = .536). BRAF mutation was predictive of LN metastasis only in group II ( P = .026).

Conclusion. BRAF mutation of PTC may have differential predictive values for LN metastasis, according to tumor size.

Thyroid cancer and lymph node metastases

There is considerable controversy about the prognostic implications of lymph node metastases in patients with papillary thyroid cancer and whether patients with papillary thyroid cancer should have a prophylactic or selective central (level VI) neck dissection. Some experts report that a prophylactic ipsilateral neck dissection results in fewer patients having elevated thyroglobulin levels but others do not agree. A comprehensive review of the literature suggests that the presence of macroscopic metastases of papillary thyroid cancer in cervical lymph nodes results in a higher recurrence rate and increased death rate, especially in patients 45 years of age or older, whereas microscopic nodal metastases do not appear to adversely influence survival. Until more information is available we recommend preoperative ultrasonography and a selective ipsilateral neck dissection for patients with papillary thyroid cancer.

Prophylactic central lymph node dissection for clinically node-negative papillary thyroid microcarcinoma: influence on serum thyroglobulin level, recurrence rate, and postoperative complications

BACKGROUND

In papillary thyroid microcarcinoma (PTMC), regional lymph node metastasis (LNM) is associated with a increased locoregional recurrence rate. Yet, prophylactic central lymph node dissection (CLND) targeting subclinical central LNM continues to be a matter of debate in the treatment of PTMC, which generally carries an excellent prognosis. The aim of our study was to investigate the benefits and risks of prophylactic CLND in patients with clinically node-negative PTMC.

METHODS

This study included 232 patients who underwent surgery for clinically node-negative PTMC from 1999 to 2006. Of these 232 patients, 113 underwent only total thyroidectomy (TT) and 119 underwent TT in conjunction with prophylactic bilateral CLND (TT with CLND). We then compared serum thyroglobulin (Tg) levels, recurrence rates, and postoperative complications between the 2 groups (TT only and TT with CLND).

RESULTS

The postoperative stimulated serum Tg level was significantly less in the TT with CLND group than in the TT only group (1.07 vs. 2.24 ng/mL, respectively; P = .022). The stimulated Tg levels in the 2 groups became similar, however, after low-dose radioactive iodine treatment (0.44 ng/mL vs. 0.69 ng/mL, respectively; P = 0.341). There was no significant difference in 3-year locoregional control rates after TT with CLND and TT only (98.3% vs. 96.5%, respectively; P = .368). Although the frequency of permanent hypocalcemia was approximately 3 times greater in the TT with CLND group (5.6%) than in the TT only group (1.8%), this finding did not reach statistical significance.

CONCLUSION

With prophylactic CLND, the postoperative Tg level can significantly decrease. However, prophylactic CLND is not helpful in decreasing short-term locoregional recurrence in patients with clinically node-negative PTMC. Finally, the risk of permanent hypocalcemia may increase after CLND.

Lymph node involvement and surgical approach in parathyroid cancer

BACKGROUND

The best surgical approach to parathyroid cancer is disputed. Recommendations vary and are built on incoherent evidence. High rates of recurrence and death require an in-depth review of underlying findings.

METHODS

This retrospective study includes 11 patients with parathyroid cancer who underwent surgery with central and/or lateral neck dissection by a single surgeon between 2005 and 2010. The diagnosis was based on histopathological criteria in all patients. Patterns of lymph node and soft tissue involvement of these and formerly reported patients were analysed based on full-text review of all published cases of parathyroid cancer.

RESULTS

In this series only 1 of 11 patients (9.1%) manifested lymph node metastasis. In the literature, lymph node metastases have been reported in only 6.5% of 972 published patients, or in 32.1% of the 196 in whom lymph node involvement was assessed by the authors. They were, with few exceptions, localised in the central compartment. Recurrence in soft tissue is more frequent than in locoregional lymph nodes.

CONCLUSION

Oncological en bloc clearance of the central compartment with meticulous removal of all possibly involved soft tissues, including a systematic central lymph node resection, may improve outcomes and should be included in the routine approach to the suspicious parathyroid lesion. There is no need for a prophylactic lateral neck dissection.

Central neck lymph node dissection for papillary thyroid cancer: the reliability of surgeon judgment in predicting which patients will benefit

BACKGROUND

The role of routine prophylactic central-neck lymph node dissection (CLND) for papillary thyroid cancer (PTC) remains controversial. We perform CLND for PTC only in patients with enlarged nodes as determined by preoperative ultrasound and intraoperative inspection and palpation.

METHODS

We identified all patients with PTC who underwent CLND during thyroidectomy (group 1) at our institution, and then we identified an equivalent number of demographically matched patients who underwent thyroidectomy without CLND (group 2) and compared the outcomes of the 2 groups.

RESULTS

In all, 191 patients were identified for each group; 49/191 (26%) patients in group 1 developed locoregional nodal recurrence (12% central neck and 21% lateral neck), compared with 11/191 (6%) patients in group 2 (3% central neck and 3% lateral neck; P < .05). Overall, 161/191 (84%) patients in group 1 were disease free at last survey, compared with 180/191 (94%) patients in group 2 (P < .05). Transient hypocalcemia was significantly greater in group 1. No difference was found in disease-specific mortality.

CONCLUSION

Surgeon assessment of the central neck compartment is an accurate predictor of which patients with PTC will benefit from CLND. Patients with nonenlarged central neck nodes who undergo total thyroidectomy without CLND have a low risk of developing recurrence.