Risks and Adequacy of an Optimized Surgical Approach to the Primary Surgical Management of Papillary Thyroid Carcinoma Treated During 1999–2006

Follow-up and Outcomes of 186 Patients With Follicular Cell-Derived Thyroid Cancer Seen at a Referral Center by One Thyroidologist in 2015

OBJECTIVE

To study the profile, management, and outcomes of follicular cell-derived thyroid cancer (FCDTC) before publication of the 2016 American Thyroid Association guidelines recommending less-aggressive thyroid cancer procedures.

METHODS

Patients with FCDTC were seen by one thyroidologist at Mayo Clinic during the 2015 calendar year. Patients underwent surgical procedures for FCDTC in 2015 or earlier at Mayo Clinic or another institution. Follow-up data were collected from January 1, 2016, through July 20, 2022. Outcomes measured included tumor characteristics, treatment methods, adverse effects, diagnostic imaging methods, and primary tumor/metastasis status at the last follow-up.

RESULTS

Of 186 included patients, 85 had total or near-total thyroidectomy. Bilateral disease was present in 35.5% of these patients, and contralateral involvement would have been missed by lobectomy for 9 (10%) patients with low-risk thyroid cancer. Additionally, 57% had positive neck lymph nodes identified during their surgical procedure, 25% (21% in central compartment) of which were undetected by preoperative ultrasonography. At the last follow-up, 65.6% of patients had no evidence of disease and 10.7% had distant metastases.

CONCLUSION

This report outlines the profile and outcomes of patients with FCDTC who were treated at a referral center before the revised 2016 American Thyroid Association guidelines. Lobectomy for low-risk FCDTC may miss some cancer in the contralateral lobe. However, the clinical importance of these missed microcarcinomas is unclear. Preoperative ultrasonography effectively predicts lateral, but not central compartment, nodal metastases.

Para-tracheal neck dissection - is dissection of the upper part of level Ⅵ necessary?

Papillary thyroid carcinoma (PTC) has a high propensity for regional metastases, however, the impact of such metastases on the outcome of the patients is minimal. The central compartment of the neck is considered the first and the most common echelon of metastases from thyroid carcinoma. Physical examination along with ultrasonography are the gold standard pre-operative evaluation of patients with PTC. Ultrasonography is highly sensitive in evaluating lateral neck nodes, however, its value in evaluating the central compartment is limited, resulting in a relatively high rate of occult metastases in this compartment. The main potential complications of para-tracheal neck dissection (PTND) are recurrent laryngeal nerve paralysis and hypocalcemia and these may be higher in patients undergoing PTND compared to thyroidectomy alone. New histological data is available showing no evidence of lymph nodes in the central compartment above a level parallel to the inferior border of the cricoid cartilage. These findings support withholding dissection of the upper para-tracheal region routinely as a part of PTND in patients with well-differentiated thyroid cancer. By doing that, the complications may be lower and identical to thyroidectomy alone, thus may abolish arguments against more common use of elective PTND in patients with thyroid carcinoma.

Neck Dissection in the Surgical Treatment of Thyroid Cancer

The incidence of thyroid cancer is increasing, largely attributable to overdetection related to prevalent diagnostic and radiologic imaging modalities. Papillary thyroid cancer remains the most common thyroid malignancy. It has a high tendency for regional metastasis to the cervical lymph nodes. The optimal management of the neck in patients with thyroid carcinoma has long been an important topic of debate. This article addresses central and lateral neck dissection, providing a simplified guide to the most up-to-date and evidence-based practices.

Comprehensive Lateral Neck Dissection in Papillary Thyroid Carcinoma may Reduce Lateral Neck Recurrence Rates

OBJECTIVE

To Identify predictors of recurrent disease following lateral neck dissection (LND) for papillary thyroid carcinoma (PTC).

METHODS

A retrospective review of patients who underwent first-time LND for PTC at our institution (2000-2015) was performed. Medical records were examined for biopsy or pathologically proven lateral neck recurrence. Differences between the groups with and without recurrence were compared. All LNDs were then classified in to two groups: "comprehensive" (CND), involving levels IIa-Vb at minimum, or "selective", labelling less extensive dissection (SND).

RESULTS

Four hundred nine patients underwent 467 LNDs. Surveillance data were available for 317 patients who underwent 362 LNDs (mean age 45 ± 16; range 18-88). The median follow-up was 64 ± 48 months (range 3-197). Recurrence was detected in 71 lateral necks (20%). The total number of lymph nodes was greater in the group without recurrence compared to those with recurrence (23 vs. 19, p = 0.02). Among patient demographics, radioactive iodine treatment, primary tumor characteristics and characteristics of nodal metastases, only an older patient age (mean 50 vs. 43 years) was associated with lateral neck recurrence (p < .01). CND was performed in 102 lateral necks and SND in 143 necks. There were 12 recurrences recorded in the CND group (12%) vs. 31 in the SND group (22%, p = .04). The majority of recurrences (70%) involved levels included in the original dissection.

CONCLUSIONS

Younger patients, more extensive dissection and a higher total number of lymph nodes removed are associated with a lower incidence of lateral neck recurrence after LND for papillary thyroid carcinoma.

Papillary Thyroid Carcinoma (PTC) in Children and Adults: Comparison of Initial Presentation and Long-Term Postoperative Outcome in 4432 Patients Consecutively Treated at the Mayo Clinic During Eight Decades (1936-2015)

BACKGROUND

Contemporary guidelines for managing PTC advise an approach wherein primary tumor and regional metastases (RM) are completely resected at first surgery and radioiodine remnant ablation (RRA) is restricted to high-risk patients, policies our group has long endorsed. To assess our therapeutic efficacy, we studied 190 children and 4242 adults consecutively treated during 1936-2015.

SUBJECTS AND METHODS

Mean follow-up durations for children and adults were 26.9 and 15.2 years, respectively. Bilateral lobar resection was performed in 86% of children and 88% of adults, followed by RRA in 30% of children and 29% of adults; neck nodes were excised in 86% of children and 66% of adults. Tumor recurrence (TR) and cause-specific mortality (CSM) details were taken from a computerized database.

RESULTS

Children, when compared to adults, had larger primary tumors which more often were grossly invasive and incompletely resected. At presentation, children, as compared to adults, had more RM and distant metastases (DM). Thirty-year TR rates were no different in children than adults at any site. Thirty-year CSM rates were lower in children than adults (1.1 vs. 4.9%; p = 0.01). Comparing 1936-1975 (THEN) with 1976-2015 (NOW), 30-year CSM rates were similar in MACIS <6 children (p = 0.67) and adults (p = 0.08). However, MACIS <6 children and adults in 1976-2015 had significantly higher recurrence at local and regional, but not at distant, sites. MACIS 6+ adults, NOW, compared to THEN, had lower 30-year CSM rates (30 vs. 47%; p < 0.001), unassociated with decreased TR at any site.

CONCLUSIONS

Children, despite presenting with more extensive PTC when compared to adults, have postoperative recurrences at similar frequency, typically coexist with DM and die of PTC less often. Since 1976, both children and adults with MACIS <6 PTC have a <1% chance at 30 years of CSM; adults with higher MACIS scores (6 or more) have a 30-year CSM rate of 30%.

Decision making for the central compartment in differentiated thyroid cancer

The central compartment is a common site for nodal spread from differentiated thyroid carcinoma, often occurring in patients without clinical or ultrasonographic (US) evidence of neck lymph node metastasis (cN0). However, the role of elective central compartment neck dissection (CND) among patients with DTC remains controversial. We performed a systematic literature review, also including review of international guidelines, with discussion of anatomic and technical aspects, as well as risks and benefits of performing elective CND. The recent literature does not uniformly support or refute elective CND in patients with DTC, and therefore an individualized approach is warranted which considers individual surgeon experience, including individual recurrence and complication rates. Patients (especially older males) with large tumors (>4 cm) and extrathyroidal extension are more likely to benefit from elective CND, but elective CND also increases risk for hypoparathyroidism and recurrent nerve injury, especially when operated by low-volume surgeons. Individual surgeons who perform elective CND must ensure the number of central compartment dissections needed to prevent one recurrence (number needed to treat) is not disproportionate to their individual number of central compartment dissections per related complication (number needed to harm).

Optimization of the risk-benefit ratio of differentiated thyroid cancer treatment

The vast majority of differentiated thyroid cancers (DTC) are characterized by an innocuous nature, excellent patient survival, and limited treatment requirement. However, a significant proportion of affected patients is prone to receiving overtreatment, due to undertreatment concerns associated with the difficulty to differentiate them from a small minority affected by aggressive DTC. Identification of prognostic factors and development of staging systems has helped to reduce the proportion of overtreatment in DTC. However, the absolute number of overtreated patients continues to increase, as a result of an on-going incidence surge in early DTC associated with the increased application and sensitivity of modern diagnostic tools. In the present paper, we describe how DTC treatment can be optimized by thoughtful evidence-based balancing of oncologic safety against treatment associated morbidity.

Patterns of Initial Recurrence in Completely Resected Papillary Thyroid Carcinoma

BACKGROUND

Despite improvements in the surgical and medical treatment of papillary thyroid carcinoma (PTC), subsets of patients suffer from structural recurrence after initial treatment. This study evaluated the timing and patterns of recurrence in completely resected PTC patients.

METHODS

A retrospective review of a prospectively maintained thyroid cancer database was performed. The timing and patterns of recurrence were reviewed in 2250 patients with PTC >1 cm who achieved complete remission after total thyroidectomy and/or radioactive iodine treatment. Univariate and multivariate analyses were performed to identify factors predictive of recurrence patterns.

RESULTS

During 8.1 years of mean follow-up, 68 (3.0%) patients developed structural recurrences: 53 lymph node recurrences (LNR), 11 local soft tissue recurrences (LR), and four distant recurrences (DR). Two patients died of DR. Younger patients had a higher proportion of LNR, and older patients had a tendency toward LR/DR. LNR showed a peak incidence between one and three years after remission, but LR/DR showed a delayed peak incidence between two and four years. The factors that significantly increased the risk of LNR were multifocal tumor and lymph node metastasis (central/lateral). The factors that increased the risk of LR/DR were old age, large tumor size (>2 cm), and lateral lymph node metastasis. In addition, central neck dissection significantly reduced subsequent LR/DR.

CONCLUSION

Patterns of recurrence after complete PTC resection are variable and associated with specific clinicopathologic factors. Understanding the timing and patterns of recurrence may lead to more effective adjuvant treatment and improved long-term follow-up strategies.

Incidence and Risk Factors for Occult Level 3 Lymph Node Metastases in Papillary Thyroid Cancer

BACKGROUND

Papillary thyroid cancer (PTC) frequently disseminates into cervical lymph nodes. Lateral node involvement is described in up to 50 % patients undergoing prophylactic lateral neck dissection. This study aimed to assess this finding and identify which factors predict for occult lateral node disease.

METHODS

Patients with fine needle aspiration-confirmed PTC (Bethesda V or VI), without evidence of cervical lymph node metastases, underwent a total thyroidectomy with prophylactic ipsilateral central and level 3 dissection. Level 3 nodes were removed by compartmental dissection or by sampling the sentinel nodes overlying the jugular vein, according to surgeon preference. Data were collected prospectively from January 2011 to August 2014. Statistical analysis was performed by SPSS software.

RESULTS

A total of 137 patients underwent total thyroidectomy with prophylactic ipsilateral central and level 3 dissection for PTC. The incidence of occult level 3 disease was 30 % (41/137 patients). A total of 48 % of patients (66/137) harbored occult central neck disease. A total of 80.5 % of patients with pN1b disease had macrometastases (≥2 mm), and 15 % exhibited skip metastases with central compartment sparing. In patients with pN1b disease, a median of 6 level 3 nodes were retrieved, with an average involved nodal ratio of 0.29. Multivariate regression demonstrated risk factors for occult lateral neck metastasis include tumor size (odds ratio 1.1), upper pole tumors (odds ratio 6.6), and vascular invasion (odds ratio 3.2) (p < 0.05).

CONCLUSIONS

PTC is associated with a significant incidence of occult central and lateral nodal metastases. In patients undergoing prophylactic central neck dissection, inclusion of level 3 dissection should be considered in patients with large upper lobe cancers.

Intermediate-risk differentiated thyroid carcinoma patients who were surgically ablated do not need adjuvant radioiodine therapy: long-term outcome study

OBJECTIVE

The mute question is whether patients with DTC of intermediate risk of recurrence, second most common presentation, who were surgically ablated in the first place, ever needed adjuvant RAI therapy? This study exclusively evaluated the long-term outcome in intermediate-risk patients with DTC.

DESIGN

Two-arm retrospective cohort study conducted between years 1991 and 2012.

SETTING

Institutional practice.

PATIENTS

Intermediate-risk DTC patients, with pathologically proven T1/2 N1 M0, T3 with/without N1 M0 disease, with a minimum follow-up of 12 months, were included. Of 254 patients who fulfilled the inclusion/exclusion criteria, 125 patients were surgically ablated (Gr-I) and 129 patients had significant remnant and/nodal disease (Gr-II). No radioiodine in Gr-I and adjuvant RAI therapy was administered in Gr-II patients.

MEASUREMENTS

Baseline characteristics were compared and overall survival, event-free survival, disease-free survival/overall remission rates and recurrence rates were calculated for both the groups.

RESULTS

All baseline patient characteristics were comparable except 24-h RAIU between two groups. Depending on adjuvant radioiodine therapy outcome, Gr-II patients were subclassified as Gr-IIa (ablated) and Gr-IIb (not ablated). With a median follow-up duration of 10·3 years (range: 1-21 years), 12/125 (9·6%) patients had disease recurrence and 10 (8%) showed persistent disease in Gr-I. In Gr-IIa, 6/102 (5·9%) patients recurred but only one of them was successfully ablated with (131) I, and 5 (4·9%) had persistent disease. However, in Gr-IIb, 27 patients who failed first-dose adjuvant RAI therapy, 8/27 (29·6%) showed persistent disease (P = 0·000). Overall survival was 100%; however, disease-free survival rates were 92% and 90%, in Gr-I and Gr-II, respectively.

CONCLUSION

Intermediate-risk surgically ablated patients do not need adjuvant RAI therapy and patients who failed to achieve ablation with first dose of (131) I may be dynamically risk stratified as high-risk category and managed aggressively.

Giant Posttraumatic Cervical Hematoma: Acute Presentation of Papillary Thyroid Carcinoma in an Adolescent

OBJECTIVE

To describe a rare case of acute presentation of papillary thyroid carcinoma (PTC).

CLINICAL PRESENTATION AND INTERVENTION

A 19-year-old male presented with an expanding cervical mass following blunt trauma. A computed tomography scan revealed a mass suspected to be hematoma that was compressing the vessels and thereby deviating the trachea. Immediate surgery was performed. Neither vascular injury nor active bleeding was seen; instead, a solid, hematoma-like tumefaction in the right thyroid lobe was revealed. A total thyroid lobectomy was performed. A histologic paraffin section confirmed a PTC that was permeated by hematoma.

CONCLUSION

This was a unique case of an acute, life-threatening presentation of previously asymptomatic PTC in an adolescent.

Central neck dissection in the treatment of well-differentiated thyroid cancer

Therapeutic central compartment neck dissection (CCND) is required for confirmed nodal metastasis in patients with differentiated thyroid cancer. The need for routine prophylactic CCND in patients with papillary thyroid cancer is controversial. This article presents the current evidence to inform the debate against the background of the recommendations of US and British thyroid cancer guidelines. Potential advantages of pCCND include reduced local recurrence, preventing the need for further central compartment surgery and improved staging. Opponents claim that there is no proven patient benefit and that there is increased risk of recurrent laryngeal nerve injury and hypocalcemia.

Long-Term Outcomes Following Therapy in Differentiated Thyroid Carcinoma: NTCTCS Registry Analysis 1987-2012

CONTEXT

Initial treatments for patients with differentiated thyroid cancer are supported primarily by single-institution, retrospective studies, with limited follow-up and low event rates. We report updated analyses of long-term outcomes after treatment in patients with differentiated thyroid cancer.

OBJECTIVE

The objective was to examine effects of initial therapies on outcomes.

DESIGN/SETTING

This was a prospective multi-institutional registry.

PATIENTS

A total of 4941 patients, median follow-up, 6 years, participated.

INTERVENTION

Interventions included total/near-total thyroidectomy (T/NTT), postoperative radioiodine (RAI), and thyroid hormone suppression therapy (THST).

MAIN OUTCOME MEASURE

Main outcome measures were overall survival (OS) and disease-free survival using product limit and proportional hazards analyses.

RESULTS

Improved OS was noted in NTCTCS stage III patients who received RAI (risk ratio [RR], 0.66; P = .04) and stage IV patients who received both T/NTT and RAI (RR, 0.66 and 0.70; combined P = .049). In all stages, moderate THST (TSH maintained subnormal-normal) was associated with significantly improved OS (RR stages I-IV: 0.13, 0.09, 0.13, 0.33) and disease-free survival (RR stages I-III: 0.52, 0.40, 0.18); no additional survival benefit was achieved with more aggressive THST (TSH maintained undetectable-subnormal). This remained true, even when distant metastatic disease was diagnosed during follow-up. Lower initial stage and moderate THST were independent predictors of improved OS during follow-up years 1-3.

CONCLUSIONS

We confirm previous findings that T/NTT followed by RAI is associated with benefit in high-risk patients, but not in low-risk patients. In contrast with earlier reports, moderate THST is associated with better outcomes across all stages, and aggressive THST may not be warranted even in patients diagnosed with distant metastatic disease during follow-up. Moderate THST continued at least 3 years after diagnosis may be indicated in high-risk patients.

Recurrence of papillary thyroid cancer after optimized surgery

Recurrence of papillary thyroid cancer (PTC) after optimized surgery requires a full understanding of the disease, especially as it has changed in the last 15 years, what comprises optimized surgery, and the different types and implications of disease relapse that can be encountered. PTC has evolved to tumors that are much smaller than previously seen, largely due to various high quality imaging studies obtained for different reasons, but serendipitously identifying thyroid nodules that prove to be papillary thyroid microcarcinomas (PTMC). With rare exception, these cancers are cured by conservative surgery without additional therapy, and seldom result in recurrent disease. PTC is highly curable in 85% of cases because of its rather innocent biologic behavior. Therefore, the shift in emphasis from disease survival to recurrence is appropriate. As a result of three technologic advances-high-resolution ultrasound (US), recombinant TSH, and highly sensitive thyroglobulin (Tg)-disease relapse can be discovered when it is subclinical. Endocrinologists who largely control administration of radioactive iodine have used it to ablate barely detectable or even biochemically apparent disease, hoping to reduce recurrence and perhaps improve survival. Surgeons, in response to this new intense postoperative surveillance that has uncovered very small volume disease, have responded by utilizing US preoperatively to image this disease, and incorporated varying degrees of lymphadenectomy into their initial treatment algorithm. Bilateral thyroid resection-either total or near-total thyroidectomy-remains the standard for PTC >1 cm, although recent data has re-emphasized the value of unilateral lobectomy in treating even some PTC measuring 1-4 cm. Therapeutic lymphadenectomy has universal approval, but when lymph nodes in the central neck are not worrisome to the surgeon's intraoperative assessment, although that judgment in incorrect up to 50%, whether they should be excised has reached a central point of controversy. Disease relapse can occur individually or in combination of three different forms: lymph node metastasis (LNM), true soft tissue local recurrence, and distant disease. The latter two are worrisome for potentially life-threatening consequences whereas nodal metastases are often persistent from the initial operation, and mostly comprise a biologic nuisance rather than virulent disease. A moderate surgical approach of bilateral thyroid resection, with usual central neck nodal clearance, and lateral internal jugular lymphadenectomy for node-positive disease can be performed safely, and with about a 5% recurrence rate.

American Thyroid Association statement on preoperative imaging for thyroid cancer surgery

BACKGROUND

The success of surgery for thyroid cancer hinges on thorough and accurate preoperative imaging, which enables complete clearance of the primary tumor and affected lymph node compartments. This working group was charged by the Surgical Affairs Committee of the American Thyroid Association to examine the available literature and to review the most appropriate imaging studies for the planning of initial and revision surgery for thyroid cancer.

SUMMARY

Ultrasound remains the most important imaging modality in the evaluation of thyroid cancer, and should be used routinely to assess both the primary tumor and all associated cervical lymph node basins preoperatively. Positive lymph nodes may be distinguished from normal nodes based upon size, shape, echogenicity, hypervascularity, loss of hilar architecture, and the presence of calcifications. Ultrasound-guided fine-needle aspiration of suspicious lymph nodes may be useful in guiding the extent of surgery. Cross-sectional imaging (computed tomography with contrast or magnetic resonance imaging) may be considered in select circumstances to better characterize tumor invasion and bulky, inferiorly located, or posteriorly located lymph nodes, or when ultrasound expertise is not available. The above recommendations are applicable to both initial and revision surgery. Functional imaging with positron emission tomography (PET) or PET-CT may be helpful in cases of recurrent cancer with positive tumor markers and negative anatomic imaging.

Papillary thyroid cancer: strategies for optimal individualized surgical management

OBJECTIVE

The goal of this article was to describe the optimal individualized surgical management of patients with papillary thyroid cancer (PTC).

METHODS

This summary reviews the relevant literature that takes into account description of the context of disease incidence, current practice guidelines, controversies in the management of thyroid resection and management of central neck lymph nodes, alternative methods of treatment, and evidence from the author's institution to support the final recommendations.

RESULTS

Combining the rationale for treatment decisions from the Mayo Clinic's surgical management of PTC, plus recently published large institutional series and a meta-analysis of patient outcomes, the recommendations for PTC >1 cm include the following: (1) preoperative ultrasound to identify and map the location of lateral jugular lymph node metastasis; (2) bilateral total or near-total thyroidectomy; (3) routine central neck (compartment VI) lymph node dissection; and (4) inclusion of lateral neck lymph node dissection when indicated. Alterations are advised depending on either the level of expertise or anatomic findings at the time of performing the thyroidectomy and lymph node dissection.

CONCLUSIONS

Because all of the data presented from the Mayo Clinic and the literature fall short of Level 1 evidence, these recommendations should not be considered dogmatic nor should they exclude reasonable alternatives that are also presented.

Solitary lateral neck node metastasis in papillary thyroid carcinoma

Background

Papillary thyroid carcinoma (PTC) is associated with a high incidence of regional node metastasis, but the patterns of lateral neck node metastasis (LNM) vary. Occasionally, a solitary LNM (SLNM) is seen in PTC patients. We therefore assessed whether selective single level node dissection is appropriate in PTC patients with SLNM.

Methods

We retrospectively reviewed the medical records of 241 PTC patients who underwent total thyroidectomy with central neck dissection plus ipsilateral internal jugular node dissection (level II to IV) between January 2010 and December 2011. Of these patients, 51 had SLNM and 190 had multiple LNM (MLNM). The clinicopathologic characteristics of the two groups were compared.

Results

Age, gender ratio, and numbers of lateral neck nodes harvested (29.4 ± 11.0 versus 30.3 ± 9.5; P = 0.574) were similar in the SLNM and MLNM groups. Mean primary tumor size was significantly smaller in the SLNM than in the MNLM group (1.03 cm versus 1.35 cm; P = 0.037). The proportion of patients with primary tumor ≤ 1 cm was significantly greater in the SLNM group (60.8% versus 38.4%; P = 0.006), whereas the proportion with maximal node size ≤ 0.7 cm (28.9% versus 73.3%; P <0.001) and the proportion with capsular invasion (62.7% versus 83.7%, P = 0.002) were significantly lower in the SLNM than in the MLNM group.

Conclusions

Selective single level neck dissection can be considered as an alternative to systemic lateral neck dissection in PTC patients with SLNM, maximal metastatic node size ≤ 0.7 cm, and no extrathyroidal invasion.

Referral patterns for patients with high-risk thyroid cancer

OBJECTIVE

Knowledge of referral patterns for specialty cancer care is sparse. Information on both the need and reasons for referral of high-risk, well-differentiated thyroid cancer patients should provide a foundation for eliminating obstacles to appropriate patient referrals and improving patient care.

METHODS

We surveyed 370 endocrinologists involved in thyroid cancer management. From information in a clinical vignette, respondents were asked to identify the reasons they would need to refer a high-risk patient to a more specialized facility for care. We performed multivariable analysis controlling for hospital and physician characteristics.

RESULTS

Thirty-two percent of respondents reported never referring thyroid cancer patients to another facility. Of those that would refer a high-risk patient to another facility, the opportunity for a patient to enter a clinical trial was the most common reason reported (44%), followed by high-dose radioactive iodine (RAI) with or without dosimetry (33%), lateral neck dissection (24%), and external beam radiation (15%). In multivariable analysis, endocrinologists with a higher percentage of their practice devoted to thyroid cancer care were significantly less likely to refer patients to another facility (P = .003).

CONCLUSION

The majority of endocrinologists treating thyroid cancer patients report referring a high-risk patient to another facility for some or all of their care. Knowledge of the patterns of physician referrals and the likelihood of need for referral are key to understanding discrepancies in referral rates and obstacles in the referral process.

Prophylactic lymph node dissection in papillary thyroid carcinoma: is there a place for lateral neck dissection?

BACKGROUND

Cervical lymph node (LN) metastases are common in patients with papillary thyroid carcinoma (PTC), and they have a negative impact on recurrence. The management of preoperatively node-negative (N0) PTC is still controversial. The aim of our study was to describe the results of a prophylactic bilateral lymph node dissection (LND) and to investigate its impact on recurrence.

METHODS

From 2003 to 2011, we analyzed 603 consecutive preoperatively N0 PTC patients. For each patient, we reviewed demographics data, tumor characteristics, pattern and risk factors of LN metastasis, and outcome.

RESULTS

Lymph node metastases were found in 23 % of patients: 19 % in the central compartment and 8 % in the lateral compartment, including 1 % in the lateral compartment on the opposite side from the tumor. Multivariate analysis showed that hyperthyroidism and extrathyroidal invasion of the tumor were significantly associated with LN metastasis. Further analysis showed that localization of the tumor in the upper third of the thyroid lobe and metastatic LN in the central compartment were independent risk factors for lateral LN metastasis. During the 4.3-year follow-up, 23 recurrences were observed (4 %), including 5 in the central compartment. Recurrence rates were 2 % in the N0 group, 5 % in N1a patients, and 22 % in N1b patients (p < 0.001).

CONCLUSIONS

In preoperatively N0 PTC patients, LN metastases are frequent in central and ipsilateral lateral compartments. Prophylactic LND in the central and ipsilateral lateral compartments should therefore be recommended in the presence of PTC to identify high-risk patients.

Predictive factors for extrathyroidal extension of papillary thyroid carcinoma based on preoperative sonography

OBJECTIVES

The purpose of this study was to evaluate the diagnostic performance and predictive factors of extrathyroidal extension of papillary thyroid carcinoma based on preoperative sonography.

METHODS

Preoperative sonography was performed for 568 patients who underwent surgery for papillary thyroid cancer between May 2009 and December 2010. Patients' T stages based on preoperative sonography were compared with their T stages based on pathologic examination, and we statistically analyzed the discriminatory performance of sonography. Among the 568 patients enrolled in this study, we selected 320 patients in whom extrathyroidal extension was suspected on sonography. We analyzed several predictive factors for extrathyroidal extension.

RESULTS

Two hundred seventy-five of the 568 patients were proven to have pathologic extrathyroidal extension of papillary thyroid cancer after surgery (75.9% diagnostic accuracy, 83.3% sensitivity, 68.9% specificity, 71.6% positive predictive value, and 81.5% negative predictive value). Of 320 patients with sonographically suspected extrathyroidal extension, a larger lesion size (P < .001) and a higher lymph node stage on sonography (P = .004) were the best predictors of extrathyroidal extension among the features that we measured. There were no significant differences in terms of the lesion site or thyroid parenchymal background echogenicity. Thyroid capsular protrusion had a higher predictive value than the abutting ratio (P = .001). However, increasing the abutting ratio enabled the prediction of extrathyroidal extension on sonography (P = .009).

CONCLUSIONS

Preoperative sonography is a helpful tool for predicting pathologic extrathyroidal extension of papillary thyroid cancer. In particular, clinicians should focus on the lesion size, nodal stage, and abutment or capsular protrusion of the lesion while performing sonography because these are the most useful predictive factors for extrathyroidal extension.

Pediatric endocrine surgery: a 20-year experience at the Mayo Clinic

CONTEXT

Surgically managed endocrinopathies are rare in children. Most surgeons have limited experience in this field. Herein we report our operative experience with pediatric patients, performed over two decades by high-volume endocrine surgeons.

SETTING

The study was conducted at the Mayo Clinic (a tertiary referral center).

PATIENTS

Patients were <19 years old and underwent an endocrine operation (1993-2012).

MAIN OUTCOME MEASURES

Demographics, surgical procedure, diagnoses, morbidity, and mortality were retrospectively reviewed.

RESULTS

A total of 241 primary cases included 177 thyroid procedures, 13 neck dissections, 24 parathyroidectomies, 14 adrenalectomies, 7 paragangliomas, and 6 pancreatic procedures. Average age of patients was 14.2 years. There were 133 total thyroidectomies and 40 hemithyroidectomies. Fifty-three cases underwent a central or lateral neck dissection. Six-month follow-up was available for 98 total thyroidectomy patients. There were four cases of permanent hypoparathyroidism (4%) and no permanent recurrent laryngeal nerve (RLN) paralyses. Sequelae of neck dissections included temporary RLN neurapraxia and Horner's syndrome. Parathyroidectomy was performed on 24 patients: 20 with primary hyperparathyroidism (HPT), three with tertiary HPT, and one with familial hypocalciuric hypocalcemia. Three patients (16%) had recurrent HPT, all with multiglandular disease. One patient had temporary RLN neurapraxia. We performed seven bilateral and seven unilateral adrenalectomies; eight were laparoscopic. Indications included pheochromocytoma, Cushing's syndrome, adrenocortical carcinoma, congenital adrenal hyperplasia, and ganglioneuroma. One death was due to adrenocortical carcinoma. Five paraganglioma patients had succinate dehydrogenase subunit B mutations, and one recurred. Six patients with insulinoma underwent enucleation (n = 5) or distal pancreatectomy (n = 1). A single postoperative abscess was managed nonoperatively.

CONCLUSION

Pediatric endocrine procedures are uncommon but can be safely performed with complication rates comparable to those of the adult population. It is imperative that these operations be performed by high-volume surgeons.

Low-risk papillary thyroid cancer: times are changing

The prevalence of papillary thyroid cancer (PTC), particularly of low-risk PTC (MACIS <6), is rising due to the increasingly use of neck imaging techniques, fine-needle aspiration and whole body PET scans. Observational cohort studies carried out in the last two decades suggest that low-risk PTC are being overtreated due to the current management paradigm being built on studies done in the 70s and 80s that still echo in some influential guidelines. With the progressive adoption of total thyroidectomy and central neck dissection as the mainstay of treatment for PTC, and suppressed basal thyroglobulin and neck ultrasound once a year as the essential tools for follow-up, the use of radioiodine ablation, body scans and stimulated thyroglobulin concentrations has become obsolete for the vast majority of patients with low-risk PTC. Future guidelines on the management of differentiated thyroid cancer should discuss separately three different diseases: low-risk PTC, high-risk PTC and follicular cancer.

The relationship between extent of thyroid cancer surgery and use of radioactive iodine

By linking surgeon surveys to the National Cancer Database, we found that surgeons' tendency to perform more extensive thyroid resection is associated with greater use of radioactive iodine for stage I thyroid cancer.

OBJECTIVE

To determine the relationships between surgeon recommendations for extent of resection and radioactive iodine use in low-risk thyroid cancer.

BACKGROUND

There has been an increase in thyroid cancer treatment intensity; the relationship between extent of resection and medical treatment with radioactive iodine remains unknown.

METHODS

We randomly surveyed thyroid surgeons affiliated with 368 hospitals with Commission on Cancer-accredited cancer programs. Survey responses were linked to the National Cancer Database. The relationship between extent of resection and the proportion of the American Joint Committee on Cancer stage I well-differentiated thyroid cancer patients treated with radioactive iodine after total thyroidectomy was assessed with multivariable weighted regression, controlling for hospital and surgeon characteristics.

RESULTS

The survey response rate was 70% (560/804). Surgeons who recommend total thyroidectomy over lobectomy for subcentimeter unifocal thyroid cancer were significantly more likely to recommend prophylactic central lymph node dissection for thyroid cancer regardless of tumor size (P < 0.001). They were also more likely to favor radioactive iodine in patients with intrathyroidal unifocal cancer ≤1 cm (P = 0.001), 1.1-2 cm (P = 0.004), as well as intrathyroidal multifocal cancer ≤1 cm (P = 0.004). In multivariable analysis, high hospital case volume, fewer surgeon years of experience, general surgery specialty, and preference for more extensive resection were independently associated with greater hospital-level use of radioactive iodine for stage I disease.

CONCLUSIONS

In addition to surgeon experience and specialty, surgeons' tendency to perform more extensive thyroid resection is associated with greater use of radioactive iodine for stage I thyroid cancer.

Variation in the management of thyroid cancer

CONTEXT

Little is known about practice patterns in thyroid cancer, a cancer that is increasing in incidence.

OBJECTIVE

We sought to identify aspects of thyroid cancer management that have the greatest variation.

DESIGN/SETTING/PARTICIPANTS

We surveyed 944 physicians involved in thyroid cancer care from 251 hospitals affiliated with the US National Cancer Database. Physicians were asked questions in the following four domains: thyroid surgery, radioactive iodine use, thyroid hormone replacement postsurgery, and long-term thyroid cancer management. We calculated the ratio of observed variation to hypothetical maximum variation under the assumed distribution of the response. Ratios closer to 1 indicate greater variation.

RESULTS

We had a 66% response rate. We found variation in multiple aspects of thyroid cancer management, including the role of central lymph node dissections (variation, 0.99; 95% confidence interval [CI], 0.98-1.00), the role of pretreatment scans before radioactive iodine treatment (variation, 1.00; 95% CI, 0.98-1.00), and all aspects of long-term thyroid cancer management, including applications of ultrasound (variation, 0.97; 95% CI, 0.93-0.99) and radioactive iodine scans (variation, 0.99; 95% CI, 0.97-1.00). For the management of small thyroid cancers, variation exists in all domains, including optimal extent of surgery (variation, 0.91; 95% CI, 0.88-0.94) and the role of both radioactive iodine treatment (variation, 0.91; 95% CI, 0.89-0.93) and suppressive doses of thyroid hormone replacement (variation, 1.00; 95% CI, 0.99-1.00).

CONCLUSION

We identified areas of variation in thyroid cancer management. To reduce the variation and improve the management of thyroid cancer, there is a need for more research and more research dissemination.

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.

Completion lobectomy and central compartment dissection in low-risk patients who had undergone less extensive surgery than hemithyroidectomy

Many low-risk patients with solitary papillary thyroid cancer located in one lobe had undergone surgery that was less extensive than hemithyroidectomy in China. An acceptable completion surgery regimen was suggested for these patients based on our experience. A total of 117 enrolled patients underwent completion surgery. Thirty-two patients had prior tumor resection, 46 patients had prior partial thyroidectomy and 39 patients had prior subtotal thyroidectomy. No neck dissection was performed. Reoperation was scheduled a median of 1.2 months (range, 3 days–6.5 months) after primary surgery for papillary thyroid cancer (PTC). Among the 117 patients, residual tumor was pathologically confirmed in 60 patients, with a residual rate of 51.28%. Among these 60 patients, residual tumor was identified in the thyroid bed alone in 18 patients and in compartment VI alone in 28 patients, while 14 patients exhibited residual tumor in both of these regions. Lymph node metastasis was observed in compartment VI in 42 patients (35.90%), and an average of 6.5 nodes were removed (range, 2–14 nodes for each patient). Additionally, 3.14 positive lymph nodes were removed on average from each of the 42 patients. We conclude that the completion regimen, including the ipsilateral residual lobe, the isthmus and ipsilateral compartment VI (prelaryngeal, pretracheal and paratracheal lymph nodes), is reasonable and acceptable for low-risk patients undergoing surgery that is less extensive than hemithyroidectomy.

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.

Pattern of initial metastasis in the cervical lymph node from papillary thyroid carcinoma

PURPOSES

This study attempted to reveal the pattern of initial lymphatic spread in order to investigate the clinical significances of lymph node metastasis in papillary thyroid carcinoma (PTC) since such information has yet to be elucidated in previous studies.

METHODS

This study reviewed 501 consecutive patients with PTC who had been surgically treated, accompanied by routine node dissection of the central, and lateral compartments. Thirty-eight cases were found to have only one metastatic node, and 62 cases were found to have 2 or 3 metastatic nodes. The locations of these metastatic nodes were mapped, and evaluated.

RESULTS

The initial lymph node metastasis occurred equally in the lateral and central compartments (19 vs. 19 nodes). Metastatic nodes were more frequently found in the central compartment (60 and 65 %) in cases with 2- and 3-node involvements. Twenty-two (60 %) and 33 (65 %) cases had at least one instance of lateral node involvement in those cases, respectively.

CONCLUSIONS

The current results demonstrated the pattern of initial lymphatic spread in PTC cases, and indicated the importance of evaluating the lateral nodes of at least compartments III and IV for accurate pathological staging, as well as for investigating the nature of the disease.

American Thyroid Association consensus review and statement regarding the anatomy, terminology, and rationale for lateral neck dissection in differentiated thyroid cancer

BACKGROUND

Cervical lymph node metastases from differentiated thyroid cancer (DTC) are common. Thirty to eighty percent of patients with papillary thyroid cancer harbor lymph node metastases, with the central neck being the most common compartment involved. The goals of this study were to: (1) identify appropriate methods for determining metastatic DTC in the lateral neck and (2) address the extent of lymph node dissection for the lateral neck necessary to control nodal disease balanced against known risks of surgery.

METHODS

A literature review followed by formulation of a consensus statement was performed.

RESULTS

Four proposals regarding management of the lateral neck are made for consideration by organizations developing management guidelines for patients with thyroid nodules and DTC including the next iteration of management guidelines developed by the American Thyroid Association (ATA). Metastases to lateral neck nodes must be considered in the evaluation of the newly diagnosed thyroid cancer patient and for surveillance of the previously treated DTC patient.

CONCLUSIONS

Lateral neck lymph nodes are a significant consideration in the surgical management of patients with DTC. When current guidelines formulated by the ATA and by other international medical societies are followed, initial evaluation of the DTC patient with ultrasound (or other modalities when indicated) will help to identify lateral neck lymph nodes of concern. These findings should be addressed using fine-needle aspiration biopsy. A comprehensive neck dissection of at least nodal levels IIa, III, IV, and Vb should be performed when indicated to optimize disease control.

Role of [(18)F]-fluorodeoxy-D-glucose positron emission tomography and computed tomography in the early detection of persistent/recurrent thyroid carcinoma in intermediate-to-high risk patients following initial radioactive iodine ablation therapy

BACKGROUND

Positron emission tomography/computed tomography (PET/CT) scan has a role in the surveillance of patients with a history of thyroid carcinoma. Its efficacy after remnant ablation as far as detecting persistent or recurrent thyroid carcinoma before other surveillance methods is not known, however. In intermediate-to-high risk thyroid carcinoma patients we studied whether PET/CT scan, performed 6-12 months after the first remnant ablation, could provide more information than ultrasonography (US) and thyrotropin-stimulated serum thyroglobulin (Tg) determination with diagnostic whole-body scan (DxWBS).

METHODS

We studied 71 subjects with differentiated thyroid cancer (DTC) who were intermediate-to-high risk for persistent/recurrent disease and who had received PET/CT scan, US, and DxWBS simultaneously with stimulated Tg levels 6-12 months after remnant ablation. To evaluate the diagnostic efficacy of PET/CT scan, the sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy were calculated.

RESULTS

Ten subjects (14%) had persistent/recurrent disease detected 6-12 months after remnant ablation. Persistence/recurrence was detected in nine (12.7%) of these patients by conventional methods, including US and DxWBS, along with stimulated Tg levels. The remaining case was detected solely by a PET/CT scan, which showed a mediastinal prevascular lesion; this was confirmed by a therapeutic WBS after additional radioiodine therapy. Among the six patients whose PET/CT scan showed positive results, five had persistent/recurrent disease. The sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy of PET/CT scan for detecting persistent/recurrent thyroid carcinoma were 50%, 98.4%, 83.3%, 92.3%, and 91.5%, respectively.

CONCLUSION

In intermediate-to-high risk patients with DTC seen 6-12 months after their first remnant ablation, there is almost no complementary role for adding a PET/CT scan to conventional follow-up methods, an US and a DxWBS simultaneously with stimulated Tg levels.

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.

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.