Role of preoperative ultrasonography in the surgical management of patients with thyroid cancer

Thyroid nodules and differentiated thyroid cancer: update on the Brazilian consensus

Thyroid nodules are frequent findings, especially when sensitive imaging methods are used. Although thyroid cancer is relatively rare, its incidence is increasing, particularly in terms of small tumors, which have an uncertain clinical relevance. Most patients with differentiated thyroid cancer exhibit satisfactory clinical outcomes when treatment is appropriate, and their mortality rate is similar to that of the overall population. However, relapse occurs in a considerable fraction of these patients, and some patients stop responding to conventional treatment and eventually die from their disease. Therefore, the challenge is how to identify the individuals who require more aggressive disease management while sparing the majority of patients from unnecessary treatments and procedures. We have updated the Brazilian Consensus that was published in 2007, emphasizing the diagnostic and therapeutic advances that the participants, representing several Brazilian university centers, consider most relevant in clinical practice. The formulation of the present guidelines was based on the participants' experience and a review of the relevant literature.

The utility of intraoperative ultrasound in modified radical neck dissection: a pilot study

BACKGROUND

Although the value of surgeon-performed neck ultrasound (SPUS) for thyroid nodules has been validated, the utility of intraoperative ultrasound (US) in modified radical neck dissection (MRND) has not been reported in the literature. The aim of this study was to analyze the utility of intraoperative SPUS in assessing the completeness of MRND for thyroid cancer.

METHODS

Between 2007 and 2011, a total of 25 patients underwent MRND by 1 surgeon for thyroid cancer. All patients underwent intraoperative SPUS, which was repeated at the end of the neck dissection (completion US) to look for missed lymph nodes (LNs).

RESULTS

There were 10 male and 15 female patients. Pathology included 23 papillary and 2 medullary carcinomas. The number of LNs removed per case was 23 ± 2, and the number of positive was LNs 5 ± 1. In 4 (16%) cases, intraoperative US detected 7 residual LNs, which would have been missed, if completion US were not done. These missed LNs were located in low-level IV (3 nodes), high-level II (2 nodes), and posterior level V (2 nodes) and measured 1.4 ± 0.2 cm. At follow-up, recurrence was seen in 2 (8%) patients, including a superior mediastinal recurrence in a patient with tall cell cancer and a jugular LN recurrence at level II in another patient with papillary thyroid cancer.

CONCLUSION

This pilot study shows that intraoperative SPUS can help assess the completeness of MRND. According to our results, intraoperative completion US identifies LNs missed by palpation 16% of the time.

Surgical management of the lateral neck compartment for metastatic thyroid cancer

PURPOSE OF REVIEW

The lateral neck compartment is the second most frequent target region for metastatic papillary thyroid cancer (PTC) and medullary thyroid cancer (MTC). Lateral lymph node metastases are associated with locoregional recurrence and, when they involve either side of the neck, with mediastinal and distant metastases.

RECENT FINDINGS

For tumors originating from the upper thyroid pole, the first nodal basin is not invariably the central compartment (as for primaries arising from the inferior thyroid pole) but often the upper part of the ipsilateral lateral compartment. Lymph node dissection of the first basin may differ depending on the location of the primary tumor. Involvement of the contralateral lateral compartment is seen in PTC with extensive central compartment involvement, and in MTC with preoperative basal calcitonin levels more than 200  pg/ml (normal limit <10  pg/ml).

SUMMARY

After lateral lymph node dissection for metastatic thyroid cancer, dysfunction of lateral neck nerves is fairly common. This observation underpins the importance of striking a balance between oncological benefit and surgical risk. Lateral lymph node dissection may be warranted for an upper thyroid pole primary, for a tumor with extensive involvement of the central compartment, and for an MTC with increased basal calcitonin level of 20-200  pg/ml (ipsilateral dissection) or more than 200  pg/ml (bilateral dissection).

Pitfalls in the staging of cancer of thyroid

Thyroid cancer includes several neoplasms originating from the thyroid gland-from indolent and curable histologies of differentiated thyroid carcinoma to aggressive anaplastic thyroid carcinoma. Differentiation of thyroid nodules is problematic on CT and MR imaging unless there is evidence of extrathyroidal extension. Evaluation of regional lymph nodes is often performed clinically or with ultrasound. The retropharyngeal and mediastinal lymph nodes are better evaluated by CT and MR imaging. Nuclear scintigraphy is useful for staging and treatment of distant metastasis in differentiated thyroid carcinoma. PET may have a role in aggressive cancers. Accurate staging affects surgical management and subsequent therapy.

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.

Papillary thyroid carcinoma nodal surgery directed by a preoperative radiographic map utilizing CT scan and ultrasound in all primary and reoperative patients

BACKGROUND

To study the diagnostic accuracy of physical examination (PE), ultrasonography (US), contrastenhanced computed tomography (CT) and in preoperative detection of macroscopic nodal metastasis in primary/recurrent papillary thyroid carcinoma (PTC) patients to determine if the routine addition of CT would be beneficial in accurate preoperative lymph-node surgery planning.

METHODS

In a tertiary center prospective study, 162 PTC patients underwent preoperative lymph-node evaluation by PE, US, and CT. Sensitivity, specificity, positive/negative predictive value (PPV/NPV) of each nodal detection technique were calculated in central/lateral cervical compartments. The gold standard for diagnostic-accuracy was surgical pathology.

RESULTS

In patients undergoing primary (Group I)/revision (Group II) surgical treatment for PTC, combined US/CT yielded significantly higher sensitivity for macroscopic lymph-node detection in both lateral and central neck, most marked in Group I-central compartment.

CONCLUSIONS

Combined preoperative US/CT provides reliable, objective, preoperative macroscopic nodal metastasis map to design rational nodal surgery in primary/revision PTC patients.

Surgeon-performed ultrasound predictors of malignancy in patients with Hürthle cell neoplasms of the thyroid

BACKGROUND

Fine-needle aspiration cannot reliably determine malignancy in patients with Hürthle cell neoplasms (HCNs) of the thyroid. Thyroid nodule size and characteristics determined by surgeon-performed ultrasound (SUS) may be useful for predicting malignancy in HCN preoperatively. This study examined whether tumor size and features by SUS can reliably predict malignancy in patients with HCN.

MATERIALS AND METHODS

We performed a retrospective review of 84 patients with HCN by fine-needle aspiration, who underwent SUS and thyroidectomy from 2002 to 2010. All patients underwent thyroid lobectomy with isthmusectomy unless there was a history of radiation exposure, familial thyroid cancer, obstructive symptoms, bilateral nodules, and/or patient preference, in which case total thyroidectomy was performed. Tumor size and malignant features by SUS were correlated with final histopathology using multivariate regression analysis.

RESULTS

On final histopathology, 29 patients had malignant thyroid nodules and 55 patients had benign ones. There were no statistically significant differences in terms of age, race, ethnicity, or gender between HCN patients who revealed malignant or benign nodules on final pathology. Tumor size ≥ 4 cm measured by SUS did not predict malignancy in HCN. Hypoechogenicity and hyperechogenicity were significantly associated with malignancy, whereas isoechogenicity was predictive of benignity (P = 0.044). No other ultrasonographic features were predictive for thyroid carcinoma by multivariate analysis.

CONCLUSIONS

Tumor size and features determined by SUS do not reliably predict malignancy in patients with HCN. Such patients at risk for malignancy should initially undergo thyroid lobectomy for definitive diagnosis.

Quantitative shear wave elastography as a prognostic implication of papillary thyroid carcinoma (PTC): elasticity index can predict extrathyroidal extension (ETE)

OBJECTIVE

To investigate whether the quantitative elasticity index of shear wave elastography (SWE) can predict extrathyroidal extension (ETE) of papillary thyroid carcinoma (PTC) preoperatively.

METHODS

A total of 208 patients with pathology confirmed PTC whom underwent SWE during preoperative staging US between April 2011 to June 2012 were included.SWE indices of E mean, E max, E min of the index malignancy, the ratios between E mean of the lesion and parenchyma (E ratio-P), and muscle (E ratio-M), and grayscale US findings, including ETE, multifocality, bilaterality, and central and lateral lymph node (LN) metastasis were evaluated. The correlations of SWE indices and grayscale US findings with pathologic prognostic factors of PTC were analyzed by Chi square or Fisher's exact test, and multivariate regression analysis.

RESULTS

ETE was associated with E mean, E max, E min, and E ratio-M (P = 0.005, 0.009, 0.016 and <0.001, respectively), multifocality was associated with E mean, E max, and E min (P = 0.028, 0.007, and 0.004, respectively), and central LN metastasis was associated with E ratio-M (P = 0.03). On multivariate analysis, E mean and E min were independent factors for predicting ETE (P = 0.032, 0.049, respectively).

CONCLUSIONS

Quantitative elasticity index of SWE could predict pathologic ETE, and SWE could be a complimentary method to grayscale US for preoperative prediction of prognostic factors of 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.

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.

Ultrasonographic guideline for thyroid nodules cytology: single institute experience

Purpose

The main issue with the current ultrasonography (US) guidelines is the overestimation of malignant and indeterminate nodules as they do not aid in making decisions to treat patients. To overcome this, new US guidelines for thyroid nodules that have been shown to be better correlated with cytologic results have been proposed. We also suggested specific indications for US-guided fine needle aspiration (FNA) using the new US guidelines.

Methods

Clinical and pathologic data from 925 patients and 1,419 thyroid nodules were retrospectively collected. All subjects underwent US- and US-guided FNA at Department of Surgery, Wonju Christian Hospital, between March 2010 and July 2011. Sensitivity, specificity, accuracy, positive predictive value (PPV), and negative predictive value (NPV) were calculated for both the current guidelines and the new guidelines.

Results

The accuracy, sensitivity, specificity, PPV, and NPV for the current guidelines in predicting malignancy were 24.1%, 99.3%, 62.2%, 25.0%, and 99.8%, respectively. The accuracy, sensitivity, specificity, PPV, and NPV for the new guidelines in predicting malignancy were 66.0%, 96.0%, 86.7%, 47.7%, and 99.4%, respectively.

Conclusion

The use of the new US guidelines allow for a more accurate and specific diagnosis and a better treatment plan than the current guidelines. Additionally, the use of the new FNA guidelines may help prevent unnecessary FNAs and promote cost-effective follow-up for patients.

Disease outcomes and nodal recurrence in patients with papillary thyroid cancer and lateral neck nodal metastases

BACKGROUND

The prognostic influence of lateral neck nodal metastases present at the time of diagnosis of papillary thyroid cancer (PTC) remains controversial. This study aims to document disease outcomes and nodal recurrence rates in such patients.

METHODS

Patients with PTC and lateral neck nodal metastases who underwent concurrent total thyroidectomy, central and lateral compartment neck dissection between 2000 and 2010 were identified from the prospectively maintained surgical databases of The University of Sydney and University of Wisconsin Endocrine Surgical Units. Disease outcomes and nodal recurrence rates were compared at 12 months post-operatively and in longer-term follow-up.

RESULTS

During this 11-year period, 121 patients were identified. Mean age was 45 years; 58% were female and 98% underwent post-operative radioactive iodine ablation. At a median follow-up of 31 months (range 12-140), there were no disease-specific deaths and disease-free survival (defined by stimulated serum thyroglobulin (Tg) < 2.0 μg/L, negative clinical and radiological examination) was 66%. Of the 50 patients with persistently elevated Tg measured 12 months post-operatively, 15 developed clinical lateral neck nodal recurrence. All have undergone re-operative surgery. Elevated stimulated Tg at 12 months post-operatively and a nodal ratio of >30% were significantly associated with an increased risk of lateral neck nodal recurrence.

CONCLUSION

With total thyroidectomy, formal compartmental neck dissection and radioactive iodine treatment, disease-free survival can be achieved in the majority of patients with PTC and synchronous lateral neck nodal metastases. A persistently elevated Tg post-operatively and a high ratio of metastatic nodes identify patients at increased risk of locoregional recurrence.

Recent advances in the surgical treatment of differentiated thyroid cancer: a comprehensive review

Differentiated thyroid cancers have become one of the fastest growing malignancies in the world. While surgery has remained the cornerstone of management of these tumors, the surgical approach has seen numerous innovations over the past few decades. The use of video-assistance and robotics has revolutionized thyroid surgery. This paper provides a comprehensive evaluation of the different approaches to thyroid surgery, the utility of prophylactic and therapeutic lymph node dissection, and evidence-based guidelines in the treatment of differentiated thyroid cancers. Minimally invasive video-ssisted thyroidectomy is both safe and effective in the hands of the trained surgeon and, in selected patient populations, has comparative perioperative morbidity and better cosmesis as compared to conventional open thyroidectomy. It is universally accepted that therapeutic central lymph node dissection should be performed when metastatic lymph nodes are identified on physical exam, ultrasound, or intraoperatively. In the absence of overt nodal metastasis, the role of elective prophylactic central lymph node dissection remains a matter of debate and prospective, randomized studies are warranted to evaluate the utility of this procedure.

Prediction of occult central lymph node metastasis in papillary thyroid carcinoma by preoperative BRAF analysis using fine-needle aspiration biopsy: a prospective study

CONTEXT

Few reports have determined whether preoperative detection of the BRAF V600E mutation in fine-needle aspiration biopsy (FNAB) may influence determination of surgical extent such as prophylactic central lymph node dissection (CLND) in patients with papillary thyroid carcinoma (PTC).

OBJECTIVES

Our objectives were to investigate whether preoperative BRAF analysis may assist determination of surgical extent, including prophylactic CLND with variable clinicopathological risk factors for central lymph node metastasis, in patients with PTC and clinically node-negative neck.

PATIENTS AND METHODS

From July 2009 to May 2011, we prospectively enrolled 148 PTC patients with clinically node-negative neck who received a total thyroidectomy and prophylactic CLND. BRAF mutation by pyrosequencing was tested on preoperative FNAB specimens. The relationships between occult central lymph node metastasis and preoperative BRAF mutation or clinicopathological factors were analyzed. Additionally, we assessed the associations between preoperative BRAF mutation status and various clinicopathological characteristics of PTC revealed postoperatively.

RESULTS

The prevalence of the BRAF V600E mutation was 53.4%, and the rate of occult central lymph node metastasis was 25.7%. Multivariate analysis showed that tumor size over 1 cm [P = 0.006; odds ratio (OR) = 3.559], perithyroidal invasion (P = 0.023; OR = 2.893), and preoperative positive BRAF mutation (P = 0.029; OR = 2.727) were independent risk factors for the presence of occult central lymph node metastasis. BRAF mutation examined in FNAB specimens, compared with the wild-type allele, strongly predicted perithyroidal invasion (48 vs. 29%; P = 0.017), extracapsular spread (65 vs. 45%; P = 0.017), occult central lymph node metastasis (35 vs. 15%; P = 0.004), and advanced TNM stage (44 vs. 28%; P = 0.035). In the multivariate analysis, patients with preoperative positive BRAF mutation were significantly more likely (P = 0.023; OR = 2.848) to have occult central lymph node metastasis.

CONCLUSION

Preoperative BRAF analysis by FNAB and primary tumor size based on ultrasonography may assist in predicting occult central lymph node metastasis in patients with PTC and clinically node-negative neck.

Preoperative ultrasonography findings predict the need for repeated surgery in papillary thyroid cancer

OBJECTIVE

To determine the impact of neck ultrasonography in predicting papillary thyroid cancer persistence or recurrence.

METHODS

Between March 2005 and March 2009, we identified patients with a preoperative diagnosis of papillary thyroid cancer. Exclusion criteria included no documented preoperative ultrasonography and initial surgery at an outside institution. Patients with positive preoperative ultrasonography were compared with patients who had negative preoperative ultrasonography by assessing rates of neck dissection, complications, disease persistence or recurrence, and the need for repeated surgery.

RESULTS

Of 127 patients initially identified, 16 did not have preoperative ultrasonography and 4 did not have their initial surgery at our institution, leaving 107 patients in our cohort. Twenty-two patients had positive preoperative ultrasonography and 85 patients had negative preoperative ultrasonography. Patients with positive preoperative ultrasonography had a higher rate of repeated surgery than those with negative preoperative ultrasonography (27% vs 4.7%, P = .003). There was no difference in postoperative complication rates. No patients with negative preoperative ultrasonography and an ultrasound report stating specifically "no suspicious lymph nodes" required repeated surgery.

CONCLUSIONS

Negative preoperative ultrasonography with specific lymph node evaluation predicts a low risk of needing early reoperation. Positive preoperative ultrasonography may be a marker for more aggressive disease and the best predictor of the need for additional surgery in the future.

Complications of central neck dissection in patients with papillary thyroid carcinoma: results of a study on 1087 patients and review of the literature

BACKGROUND

Prophylactic central neck dissection (CND) has been proposed in the treatment of patients affected by papillary thyroid carcinoma (PTC) with clinically negative neck lymph nodes. The procedure allows pathologic staging of lymph nodes of the central compartment and treatment of the micrometastases. Nevertheless, the morbidity that its routine use adds to the total thyroidectomy must be taken into account. The aim of this study was to characterize the morbidity that CND adds to the total thyroidectomy.

METHODS

This was a retrospective study of 1087 patients with PTC and clinically negative neck lymph nodes. Patients were divided into three study groups: Group A, total thyroidectomy; Group B, total thyroidectomy and ipsilateral CND; Group C, total thyroidectomy and bilateral CND. Primary endpoints of the study were evaluated by comparing the rates of transient and permanent recurrent laryngeal nerve (RLN) injury and hypoparathyroidism in the three study groups.

RESULTS

Analysis of data showed no significant differences in the rate of transient (Group A: 3.6%, Group B: 3.9%, and Group C: 5.5%; p=0.404) and permanent (Group A: 1%, Group B: 0.5%, and Group C: 2.3%; p=0.099) RLN injury between the three study groups. Both ipsilateral CND and bilateral CND were associated with a higher rate of transient hypoparathyroidism (Group: A 27.7%, Group B: 36.1%, and Group C: 51.9%; p=0.014; odds ratio [OR]: 1.477; 95% confidence interval [CI]: 1.091-2.001; p<0.001; OR: 2.827; 95% CI: 2.065-3.870, respectively). Bilateral CND had a higher rate of permanent hypoparathyroidism (Group A: 6.3%, Group B: 7%, and Group C: 16.2%; p<0.001; OR: 2.860; 95% CI: 1.725-4.743).

CONCLUSIONS

The increased rates of transient and permanent hypoparathyroidism in our series suggest a critical review of indications for the routine use of prophylactic CND for PTC. Prophylactic CND ipsilateral to the tumor associated with total thyroidectomy may represent an effective strategy for reducing the rate of permanent hypoparathyroidism. Concomitant completion contralateral paratracheal lymph node neck dissection should be performed in presence of lymph node metastasis on intraoperative frozen-section pathology. This approach limits the use of bilateral CND to patients with intraoperative pathological findings of lymph node metastases.

Clinical predictors of right upper paraesophageal lymph node metastasis from papillary thyroid carcinoma

Background

Central and lateral lymph node metastases are quite common in patients with papillary thyroid carcinoma, and the predictors for those metastases have been well studied. Right upper paraesophageal lymph node metastasis has rarely been studied. The aim of this study was to identify the clinicopathological characteristics that may be risk factors for right upper paraesophageal lymph node metastasis in patients with papillary thyroid carcinoma.

Methods

This was a prospective observational study of 243 patients with papillary thyroid carcinoma (PTC) who underwent total thyroidectomy and comprehensive central lymph node dissection with or without lateral lymph node dissection between April 2008 and January 2010. The clinicopathologic findings from these patients were investigated and the patterns of lymph node metastasis were analyzed in the patients who had right upper paraesophageal lymph node disease.

Results

Of the 243 patients undergoing lymph node dissection, 14 had right upper paraesophageal lymph node metastases. Two of these patients had right upper paraesophageal lymph node metastasis only, without central compartment metastasis. Univariate analysis of clinicopathologic findings showed that right upper paraesophageal lymph node metastasis had significant association with larger primary tumors, multifocal tumors, extrathyroid extension, and lymphatic invasion (p <0.05 for each factor).

Conclusions

Although there were no independent predictors of right upper paraesophageal lymph node metastasis, it can be the only site of metastasis without other compartmental metastasis. Therefore, during surgery for patients with central or lateral lymph node metastases from PTC, it may be helpful to examine the right upper paraesophageal lymph nodes.

Roles of ultrasonography and computed tomography in the surgical management of cervical lymph node metastases in papillary thyroid carcinoma

AIMS

Adequate evaluation and surgical management of cervical lymph node metastasis is very important in papillary thyroid carcinoma (PTC). The aim of this study was to evaluate the impact of preoperative ultrasonography (US) and computed tomography (CT) on the surgical management of cervical lymph node metastases in PTC.

METHODS

Medical records and imaging findings were retrospectively analyzed for 252 patients with PTC who underwent thyroidectomy with neck dissection.

RESULTS

The sensitivity of both imaging techniques was lower in the central neck (US 23%, CT 41%) than in the lateral neck (US 70%, CT 82%). The specificities of US and CT were 97% and 90% in the central neck, and 84% and 64% in the lateral neck, respectively. Our surgical plans for therapeutic neck dissection were based on imaging findings in 59% of patients who underwent lateral compartment neck dissection and in 32.1% of patients who underwent central compartment neck dissection, respectively.

CONCLUSIONS

The roles of preoperative US and CT in surgical planning for central compartment neck dissection in PTC are limited because of their low sensitivity in the central neck, but US and CT may be useful in cases with non-palpable lateral neck nodes.

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.

Diagnostic adequacy of surgeon-performed ultrasound-guided fine needle aspiration biopsy of thyroid nodules

BACKGROUND

Surgeon-performed ultrasonography (US) of thyroid nodules might serve as a potential therapeutic guide to designate accurate surgical or clinical intervention.

OBJECTIVE

To evaluate the diagnostic adequacy of surgeon-performed ultrasonography guided fine needle aspiration biopsy (FNAB) of thyroid nodules, the factors responsible for diagnostic adequacy and the impact of surgeon-performed US on treatment approach.

METHODS

Retrospective review of a single surgeon performed 621 US-guided FNABs without on-site cytological specimen assessment. Outside US findings were compared to the surgeon-performed US. Measured variables and outcomes for the study included diagnostic adequacy rates and the effects of detected differences between US reports on treatment variability.

RESULTS

Diagnostic adequacy rate of surgeon-performed US-guided FNAB was determined to be 94.52% without on-site specimen evaluation by cytologist. Non-diagnostic specimens occurred in 34 of 621 (5.48%) nodules. The differences detected between the outside US and surgeon-performed US altered invasive treatment algorithm in 30 (5.47%) patients. FNAB was avoided for 15 (2.7%) patients. Total thyroidectomy became the preferred surgical option in 15 (2.7%) patients after the discovery of additional nodules in the contralateral lobe.

CONCLUSION

Surgeon-performed US offers clear clinical benefits in terms of diagnostic yield of FNAB with providing valuable additional data that might alter surgical treatment approach.

Suspicious ultrasound characteristics predict BRAF V600E-positive papillary thyroid carcinoma

BACKGROUND

Current American Thyroid Association (ATA) guidelines recommend routine cervical ultrasound (US) in thyroid nodule evaluation. Specific US characteristics can help diagnose papillary thyroid carcinoma (PTC). The aim of this blinded cohort study was to determine whether these specific US characteristics can also reliably detect the more aggressive variants of PTC that are often associated with the BRAF(V600E) mutation.

METHODS

After Institutional Review Board approval, we identified a cohort of patients from January 2007 to December 2009 with histologic PTC≥1 cm who had cervical US, initial thyroid surgery, and molecular testing for BRAF(V600E) on fine-needle aspiration biopsy or histology. Preoperative US images were evaluated by a single radiologist, who was blinded to BRAF status, for nodule size and the presence or absence of the following suspicious US features: taller-than-wide shape, ill-defined margins, hypoechogenicity, calcifications, noncystic composition, and absent halo.

RESULTS

BRAF-positivity was associated with most known suspicious US findings, including taller-than-wide shape (47% vs. 7%, p<0.001), ill-defined margins (42% vs. 9%, p<0.001), hypoechogenicity (83% vs. 36%, p<0.001), micro/macrocalcifications (87% vs. 24%, p<0.001), and absent halo (85% vs. 27%, p<0.001) but was not associated with noncystic composition. When ≥3 suspicious US features were present, BRAF-positivity was predicted with a positive predictive value of 82%. The absence of suspicious US features together with negative BRAF testing predicted PTC without extrathyroidal extension or lymph node metastasis (negative predictive value 88%).

CONCLUSIONS

With routine preoperative cervical US and molecular testing, a trained radiologist or surgeon can improve the preoperative characterization of PTC, potentially impacting risk stratification and initial surgical management.

In papillary thyroid cancer, preoperative central neck ultrasound detects only macroscopic surgical disease, but negative findings predict excellent long-term regional control and survival

BACKGROUND

Ultrasound (US) of the central neck compartment (CNC) is considered of limited sensitivity for nodal spread in papillary thyroid cancer (PTC); elective neck dissection is commonly advocated even in the absence of sonographic abnormalities. We hypothesized that US is an accurate predictor for long-term disease-free survival, regardless of the use of elective central neck dissection in patients with PTC.

METHODS

A retrospective chart review of 331 consecutive PTC patients treated with total thyroidectomy at M.D. Anderson Cancer Center between 1996 and 2003 was performed. Information retrieved included preoperative sonographic status of the CNC, surgical treatment of the neck, demographics, cancer staging, histopathological variables and use of adjuvant treatment. The endpoints for the study were nodal recurrence and survival.

RESULTS

There were 112 males and 219 females with a median age of 44 years (range 11-87). The median follow-up time for the series was 71.5 months (range 12.7-148.7). There were 151 (45.6%) patients with a T1, 58 (17.5%) with a T2, 70 (21.1%) with a T3, and 52 (15.7%) with a T4. Preoperative sonographic abnormalities were present in the CNC in 79 (23.9%) patients. During the surveillance period, 11 (3.2%) patients recurred in the central neck, with an average time for recurrence of 22.8 months. Advanced T stage (T3/T4) and abnormal US were independent prognostic factors for recurrence in the central neck (p=0.013 and p=0.005 respectively). There were 119 (35%) patients with a sonographically negative central compartment who underwent elective central neck dissection; 85 of them (71.4%) were found to be histopathologically N(+) while 34 (28.6%) were pN0. There were no differences in overall survival (p=0.32), disease specific survival (DSS; p=0.49), and recurrence-free survival (p=0.32) between these two groups. Preoperative US of the CNC was an age-independent predictor for overall survival (p<0.001), DSS (p=0.0097), and disease-free survival (p=0.0005) on bivariate Cox regression.

CONCLUSIONS

US of the central compartment is an age-independent predictor for survival and CNC recurrence-free survival in PTC. Prophylactic neck dissection of the central compartment does not improve long-term disease control, regardless of the histopathological status of the lymph nodes retrieved. Our findings emphasize the ability of US to clinically detect relevant nodal disease and support conservative management of the CNC in the absence of abnormal findings.

Prognostic implications of microscopic involvement of surgical resection margin in patients with differentiated papillary thyroid cancer after high-dose radioactive iodine ablation

OBJECTIVE

To evaluate the relationship between microscopic cancerous involvement of surgical margin and recurrence in patients with differentiated papillary thyroid cancer (PTC) who underwent total thyroidectomy followed by high-dose radioactive iodine ablation (HDRIA).

METHODS

Consecutive 197 PTC patients (184 women; mean age 44.9 years) who underwent total thyroidectomy without gross residual tumor followed by HDRIA were retrospectively reviewed. Resection margin involvement was evaluated and recurrence of the disease was assessed with clinicopathologically. Recurrence detected within 12 months after HDRIA were defined as early recurrence, detected after 12 months were defined as late recurrence.

RESULTS

The mean follow-up was 85.9 ± 16.6 months. Twelve patients (6.1%) had microscopic cancerous involvement of surgical margin [margin (+) group], and 185 patients had negative surgical resection margins [margin (-) group]. Three patients (25.0%) in the margin (+) group and 11 patients (5.9%) in the margin (-) group had early recurrence. Margin (+) group showed higher incidence of early recurrence and lower incidence of disease free compared to margin (-) group (25.0 vs. 5.9%, p < 0.01; 66.7 vs. 81.1%, p < 0.01, respectively); however, there was no difference in incidence of late recurrence between the two groups (p = 1.00). There were no significant differences in the disease-free survival between the margin (+) and margin (-) groups after exclusion of early recurrence (p = 0.78).

CONCLUSIONS

After high-dose radioactive iodine ablation, PTC patients with microscopic cancerous surgical margin involvement had a higher incidence of early recurrence and no different late recurrence rate compared to patients without microscopic cancerous surgical margin involvement.

Preoperative basal calcitonin and tumor stage correlate with postoperative calcitonin normalization in patients undergoing initial surgical management of medullary thyroid carcinoma

BACKGROUND

The optimal initial operative management of medullary thyroid cancer (MTC) and the use of biomarkers to guide the extent of operation remain controversial. We hypothesized that preoperative serum levels of calcitonin and carcinoembryonic antigen (CEA) correlate with extent of disease and postoperative levels reflect the extent of operation performed.

METHODS

We assessed retrospectively clinical and pathologic factors among patients with MTC undergoing at least total thyroidectomy; these factors were correlated with biomarkers using regression analyses.

RESULTS

Data were obtained from 104 patients, 28% with hereditary MTC. Preoperative calcitonin correlated with tumor size (P < .001) and postoperative serum calcitonin levels (P = .01) after multivariable adjustment for lymph node positivity, extent of operation, and hereditary MTC. No patient with a preoperative calcitonin level of <53 pg/mL (n = 20) had lymph node metastases. TNM stage (P = .001) and preoperative calcitonin levels (P = .04), but not extent of operation, independently correlated with the failure to normalize postoperative calcitonin. Postoperative CEA correlated with positive margins (adjusted P = 04). Neither preoperative nor postoperative CEA was correlated with lymph node positivity or extent of surgery.

CONCLUSION

Preoperative serum calcitonin and TMN stage, but not extent of operation, were independent predictors of postoperative normalization of serum calcitonin levels. Future studies should evaluate preoperative serum calcitonin levels as a determinate of the extent of initial operation.

The treatment of differentiated thyroid cancer in children: emphasis on surgical approach and radioactive iodine therapy

Pediatric thyroid cancer is a rare disease with an excellent prognosis. Compared with adults, epithelial-derived differentiated thyroid cancer (DTC), which includes papillary and follicular thyroid cancer, presents at more advanced stages in children and is associated with higher rates of recurrence. Because of its uncommon occurrence, randomized trials have not been applied to test best-care options in children. Even in adults that have a 10-fold or higher incidence of thyroid cancer than children, few prospective trials have been executed to compare treatment approaches. We recognize that treatment recommendations have changed over the past few decades and will continue to do so. Respecting the aggressiveness of pediatric thyroid cancer, high recurrence rates, and the problems associated with decades of long-term follow-up, a premium should be placed on treatments that minimize risk of recurrence and the adverse effects of treatments and facilitate follow-up. We recommend that total thyroidectomy and central compartment lymph node dissection is the surgical procedure of choice for children with DTC if it can be performed by a high-volume thyroid surgeon. We recommend radioactive iodine therapy for remnant ablation or residual disease for most children with DTC. We recommend long-term follow-up because disease can recur decades after initial diagnosis and therapy. Considering the complexity of DTC management and the potential complications associated with therapy, it is essential that pediatric DTC be managed by physicians with expertise in this area.

The role of preoperative neck ultrasounds to assess lymph nodes in patients with suspicious or indeterminate thyroid nodules

BACKGROUND AND OBJECTIVES

Currently there are no recommendations for obtaining a preoperative neck ultrasound for patients with suspicious or indeterminate thyroid nodules. Because a preoperative surgical ultrasound can detect suspicious lymph nodes that could result in ultimately altering surgical management, we chose to study which variables were predictive of this change.

METHODS

Medical records of 173 patients who presented between January 2006 and December 2010 with suspicious or indeterminate thyroid cytology were retrospectively reviewed. Clinicopathological variables were analyzed to determine factors predictive of malignancy and a change in operative approach.

RESULTS

One hundred thirty-four of 173 patients were evaluable. Seventeen of 134 (12.6%) of the preoperative ultrasounds were suspicious. Seven of 134 (5.2%) patients underwent a formal lymph node dissection based on ultrasound findings. Size of tumor, Bethesda FNAB category, and male gender were associated with malignancy while thyroid nodule microcalcifications and category of FNAB were associated with performing lymph node dissections.

CONCLUSION

Thyroid nodule microcalcifications on ultrasound and category of FNAB appear to be the best predictors of metastatic disease. Because the surgical approach was altered in only a few patients, further analysis is needed to delineate whether performing cervical ultrasound for suspicious/indeterminate nodules is cost effective.

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.

Preoperative serum thyroid stimulating hormone levels in well-differentiated thyroid carcinoma is a predictive factor for lateral lymph node metastasis as well as extrathyroidal extension in Korean patients: a single-center experience

It has been known that thyroid stimulating hormone (TSH) stimulates the growth or development of thyroid malignancy and higher serum TSH has association with both thyroid cancer incidence and advanced tumor stage. However, the role of TSH in high-risk features of well-differentiated thyroid cancer was not fully evaluated especially in Asian population. The purpose of our study is to evaluate the association of preoperative serum TSH levels with the advance of differentiated thyroid cancer and its high-risk clinicopathological features in Korean patients. We evaluated 554 patients retrospectively who underwent thyroidectomy and diagnosed as differentiated thyroid cancer during a 3-year period at Pusan National University Hospital. The preoperative TSH levels were significantly higher in the patients with extrathyroidal extension (P = 0.002) and those with lateral lymph node metastasis (P = 0.007). As the increase of the serum TSH concentration, there were significant rising trends in the prevalence of extrathyroidal extension (P = 0.009). In the patients with TSH ≥ 2.5 mIU/L, the prevalences of extrathyroidal extension (P = 0.006) and lateral lymph node metastasis (P = 0.024) were also significantly higher. Using multiple logistic regression, preoperative TSH level was a predictive factor for the presence of extrathyroidal extension (P = 0.008) and lateral lymph node metastasis (P = 0.025). Hashimoto's thyroiditis itself was not associated with the status of extrathyroidal extension and lateral lymph node metastasis. In conclusion, preoperative TSH levels were associated with lateral lymph node matastasis, a novel finding, and extrathyroidal extension in well differentiated thyroid cancer and might be useful as a preoperative supplementary marker for determining the optimal extent of differentiated thyroid cancer surgery in Korean patients.

Staging of papillary thyroid carcinoma with ultrasonography: performance in a large series

BACKGROUND

This study was designed to evaluate the performance of ultrasonography (US) for the preoperative staging of papillary thyroid carcinoma (PTC) in a large series according to the TNM classification.

METHODS

Preoperative US was performed for the evaluation of primary tumors and lymph node metastasis in 722 consecutive patients with cytologically proven PTC. Three experienced radiologists prospectively determined T and N categories of PTC. N categorization was based on compartments, including left and right lateral compartments (levels II-V) and central compartment (level VI). All patients underwent surgery and central compartment dissection. Lateral compartment dissection was selectively performed. We assessed the diagnostic performance of preoperative US for staging of PTC on the basis of pathologic findings of surgical specimens. Subgroup analysis according to suspicion of diffuse thyroid disease (DTD) on US was performed to compare US accuracies for N categorization.

RESULTS

US predicted 61.7% (142/230) of patients with multifocal PTC and 67.1% (100/149) of patients with bilateral malignancy. Overall accuracy of US for T categorization was 69.7% (503/722) and that of US for N categorization was 59% (426/722). Accuracies of sonographic categorization for N0, N1a, and N1b were 66% (276/418), 33.3% (70/210), and 85.1% (80/94), respectively. Overall US accuracy for prediction of an N category was significantly lower in patients with US-indicated DTD (51.1%, 67/131) than it was in patients without DTD (60.7%, 359/591; P = 0.043).

CONCLUSIONS

Preoperative US is a feasible technique for the preoperative staging of PTC and is helpful for the detection of lateral compartment metastasis. Presence of DTD can affect the staging of lymph node metastasis.

Cystic lymph nodes in the lateral neck as indicators of metastatic papillary thyroid cancer

OBJECTIVE

To determine whether radiographic findings portend to metastatic disease in patients with papillary thyroid carcinoma (PTC) and whether cystic lymph node metastasis can be recognized by preoperative, ultrasound-guided fine-needle aspiration (FNA).

METHODS

We performed a retrospective review of patients with cystic lymph nodes in the lateral neck identified on preoperative ultrasonography between March 1996 and December 2009. Factors examined included demographic information; stage; cytologic and final pathologic findings; and imaging characteristics including location, size, and presence of vascularity and calcifications. Time of cystic node identification in relationship to initial diagnosis was also recorded.

RESULTS

Thirty patients had cystic lymph nodes in the lateral neck on cervical ultrasonography during the study period. Among this group, 28 (93%) had PTC, 1 (3%) had papillary serous carcinoma of the ovary, and 1 (3%) had poorly differentiated thyroid cancer. Median age at initial cancer diagnosis was 41 years (range, 16-64 years). Twenty-one patients (70%) were women, and median lymph node size was 1.8 cm (range, 0.6-4.8 cm). Twenty-three patients (77%) had a solitary cystic lymph node, and the remainder had more than 1 cystic lymph node. Cystic lymph nodes were identified at initial presentation in 11 patients (37%), while cystic lymph nodes were discovered in 19 patients (63%) after the initial operation. FNA was performed on the cystic lymph nodes of 23 patients (77%). Cytologic findings were positive for metastatic disease in 18 of 23 patients (78%). Among the 5 of 23 patients with negative cytologic findings, thyroglobulin aspirate was obtained in 1 patient, confirming metastatic PTC. Final pathologic review after surgical resection of cystic lymph nodes with negative cytologic findings from FNA was consistent with metastatic disease in 4 of 5 patients (80%).

CONCLUSIONS

In patients with PTC, the presence of a cystic lymph node by ultrasonographic examination is highly suggestive of locally metastatic disease. Confirmation of metastatic PTC may sometimes be achieved with thyroglobulin aspirate from cystic lymph nodes when cytologic findings are negative. Clinicians should strongly consider surgical lymph node resection of cystic lymph nodes regardless of the preoperative cytologic findings by FNA.

Central lymph node metastasis of unilateral papillary thyroid carcinoma: patterns and factors predictive of nodal metastasis, morbidity, and recurrence

BACKGROUND

Although subclinical cervical lymph node (LN) metastases in papillary thyroid carcinoma (PTC) are common, the efficacy of prophylactic central LN dissection (CLND) is unclear. Few prospective studies have assessed the relationships between complete pathologic information regarding tumors and metastatic nodes in the central compartment. We therefore investigated the pattern and predictive indicators of central LN metastasis, morbidity, and recurrence in patients who underwent total thyroidectomy and prophylactic CLND for unilateral PTC and clinically node-negative neck (cN0) disease.

METHODS

This prospective study involved 184 patients with previously untreated unilateral PTC and cN0 who underwent total thyroidectomy and bilateral CLND. Nodal samples were divided into the prelaryngeal/pretracheal and ipsilateral and contralateral paratracheal regions, with each assessed for clinicopathologic predictors of central metastases. Postoperative morbidity and recurrence were assessed.

RESULTS

Rates of metastasis to ipsilateral and contralateral central compartments were 42.9 and 9.8%, respectively. Multivariate analysis showed that tumor size >1 cm and extrathyroidal extension were independent predictors of ipsilateral metastasis, and ipsilateral metastases independently predicted contralateral metastases (P < 0.05 each). Permanent hypoparathyroidism and incidental recurrent nerve paralysis were found in 1.6 and 0% of patients, respectively. After a mean follow-up of 46 months, none of these patients had recurrence in the central compartment.

CONCLUSIONS

Subclinical metastases are highly prevalent in the ipsilateral central neck of patients with PTC >1 cm. Contralateral central metastases, although uncommon, are associated with ipsilateral central metastases. These findings may guide the necessity and extent of prophylactic bilateral or unilateral CLND.

Influence of prophylactic central lymph node dissection on postoperative thyroglobulin levels and radioiodine treatment in papillary thyroid cancer

BACKGROUND

Prophylactic central lymph node dissection with total thyroidectomy (TT) for the treatment of papillary thyroid cancer (PTC) is controversial because of the possibility of increased morbidity with uncertain benefit. The purpose of this study is to determine whether prophylactic central neck dissection provides any advantages over TT alone.

METHODS

Retrospective cohort study of patients with PTC without preoperative evidence of lymph node involvement undergoing either TT or TT with bilateral central lymph node dissection (TT + BCLND).

RESULTS

From 2002 to 2009, 143 patients with clinically node-negative PTC underwent either TT (n = 65) or TT + BCLND (n = 78). The groups were similar in age, gender, tumor size, multifocality, angioinvasion, and metastasis/age/completeness-of-resection/invasion/size score. The presence of involved central neck lymph nodes upstaged 28.6% of patients in the TT + BCLND group to stage III disease, which resulted in higher radioactive iodine ablation doses. Stimulated serum thyroglobulin levels and the number of patients with undetectable stimulated thyroglobulin levels before and 1 year after radioactive iodine ablation were equivalent.

CONCLUSION

The addition of routine central lymph node dissection to TT for the treatment of PTC upstages nearly one third of patients over the age of 45 thereby changing the dose of radioactive iodine ablative therapy, but does not change postoperative thyroglobulin levels after completion of radioiodine treatment.

Preoperative ultrasonographic tumor characteristics as a predictive factor of tumor stage in papillary thyroid carcinoma

BACKGROUND

The purpose of this study was to evaluate the usefulness of tumor characteristics on ultrasonography for predicting the pathologic stage of papillary thyroid carcinoma.

METHODS

We evaluated 354 patients who underwent surgery for papillary thyroid carcinoma (≤2 cm). We analyzed the preoperative ultrasonography findings such as tumor size, shape, margin, echogenicity, calcification, vascularity, and contact with the capsule.

RESULTS

Tumor size, echogenicity, and contact with the capsule were predictive for the presence of extrathyroid extension. Size and echogenicity were significantly associated with central lymph node metastasis in the multivariate analysis. Some ultrasonography characteristics such as round shape, well-defined margin, and isoechoic echogenicity were negative predictive factors for extrathyroid extension and central lymph node metastasis.

CONCLUSION

Preoperative tumor characteristics on ultrasonography correlated with several prognostic factors for papillary thyroid carcinoma and may serve as preoperative supplementary markers for determining the optimal extent of surgery.