Do the level of nodal disease according to the TNM classification and the number of involved cervical nodes reflect prognosis in patients with differentiated carcinoma of the thyroid gland?

Prophylactic central neck dissection for cN0 papillary thyroid carcinoma: is there any difference between western countries and China? A systematic review and meta-analysis

Background

Recommendations for the performance of prophylactic central neck dissection (pCND) in patients with clinically node-uninvolved (cN0) papillary thyroid carcinoma (PTC) are not the same. This meta-analysis set out to compare the effectiveness of pCND with total thyroidectomy (TT) in different countries and regions, mainly between western countries and China.

Methods

The electronic databases PubMed, EMBASE, and Cochrane Library were searched for studies published until August 2022. The incidence rate of cervical lymph node metastases (LNMs), locoregional recurrences (LRRs), and postoperative complications were pooled by a random-effects model. Subgroup analyses based on different countries and regions were performed.

Results

Eighteen studies involving 5,346 patients were analyzed. In the subgroup of western countries, patients undergoing pCND with TT had a significantly lower LRR rate [69/1,804, 3.82% vs. 139/2,541, 5.47%; odds ratio (OR) = 0.56; 95% CI 0.37-0.85] and a higher rate of temporary hypoparathyroidism (HPT) (316/1,279, 24.71% vs. 194/1,467, 13.22%; OR = 2.23; 95% CI 1.61-3.08) than that of the TT alone group, while no statistically significant difference was found in the rate of permanent HPT and temporary and permanent recurrent laryngeal nerve (RLN) injury. In the Chinese subgroup, the pCND with TT group had a significantly higher incidence rate of both temporary HPT (87/374, 23.26% vs. 36/324, 11.11%; OR = 2.24; 95% CI 1.32-3.81) and permanent HPT (21/374, 5.61% vs. 4/324, 1.23%; OR = 3.58; 95% CI = 1.24-10.37) than that of the TT alone group, while no significant difference was detected in the rate of LRR and temporary and permanent RLN injury.

Conclusion

Compared with the TT alone for cN0 PTC patients, pCND with TT had a significantly lower LRR rate while having a higher temporary HPT rate in Europe, America, and Australia; however, it showed no significant difference in decreasing LRR rate while having a significantly raised rate of temporary and permanent HPT in China. More population-based results are required to advocate precision medicine in PTC.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42022358546.

A critical analysis of the current TNM classification for differentiated thyroid carcinoma in young patients: Time for a change?

Background

The current TNM classification that simply classifies differentiated thyroid carcinoma (DTC) patients younger than 55 years into stage I and stage II based on the presence or absence of distant metastases has been questioned. In this study, we reexamined the impact of T status and N status on prognosis and then developed a new prediction model to improve the predictability of cancer-specific survival (CSS) in young patients.

Materials and methods

Kaplan-Meier method was applied to calculate the CSS. Multivariable Cox proportional hazards models were used to assess the impact of T status and N status on CSS after adjustment for known covariates. The area under the receiver operating characteristic curve (AUC), C-index, Bayesian information criterion (BIC), and Akaike information criterion (AIC) were calculated to compare model performance.

Results

A total of 9,242 DTC patients younger than 55 years were enrolled in the study. After adjusting for gender, age at diagnosis, race, pathology subtype, N stage, and M stage, T3 disease [hazard ratio (HR): 3.78, P = 0.006] and T4 disease (HR: 7.96, P < 0.001) remain independent predictors of CSS. Similarly, the 10-year CSS rate of N1b disease (HR: 3.78, P < 0.001) was significantly higher than that of N0 disease after adjustment. Moreover, Kaplan-Meier survival analysis showed that the 10-year CSS of stage II disease in younger patients with DTC showed a sharp decrease compared with that in older patients with DTC (74.47% vs. 98.43%, P < 0.001). Furthermore, a modified TNM staging system based on significantly prognostic T stage and N stage was established, which showed better performance than the current TNM staging system (P < 0.05). The new prediction model is also applicable to papillary thyroid carcinoma patients and follicular thyroid carcinoma patients.

Conclusions

This is the first study to question the rationality of the current TNM staging system for patients younger than 55 years and successfully develop a new prognostic model, which improves prognostic stratification and guides individualized management.

Presence and Number of Lymph Node Metastases Are Associated With Compromised Survival for Patients Younger Than Age 45 Years With Papillary Thyroid Cancer

Purpose

Cervical lymph node metastases are recognized as a prognostic indicator only in patients age 45 years or older with papillary thyroid cancer (PTC); patients younger than age 45 years are perceived to have low-risk disease. The current American Joint Committee on Cancer staging for PTC in patients younger than age 45 years does not include cervical lymph node metastases. Our objective was to test the hypothesis that the presence and number of cervical lymph node metastases have an adverse impact on overall survival (OS) in patients younger than age 45 years with PTC.

Patients and Methods

Adult patients younger than age 45 years undergoing surgery for stage I PTC (no distant metastases) were identified from the National Cancer Data Base (NCDB; 1998-2006) and from SEER 1988-2006 data. Multivariable models were used to examine the association of OS with the presence of lymph node metastases and number of metastatic nodes.

Results

In all, 47,902 patients in NCDB (11,740 with and 36,162 without nodal metastases) and 21,855 in the SEER database (5,188 with and 16,667 without nodal metastases) were included. After adjustment, OS was compromised for patients with nodal metastases compared with patients who did not have them (NCDB: hazard ratio (HR), 1.32; 95% CI, 1.04 to 1.67; P = .021; SEER: HR, 1.29; 95% CI, 1.08 to 1.56; P = .006). After adjustment, increasing number of metastatic lymph nodes was associated with decreasing OS up to six metastatic nodes (HR, 1.12; 95% CI, 1.01 to 1.25; P = .03), after which more positive nodes conferred no additional mortality risk (HR, 0.99; 95% CI, 0.99 to 1.05; P = .75).

Conclusion

Our results suggest that cervical lymph node metastases are associated with compromised survival in young patients, warranting consideration of revised American Joint Committee on Cancer staging. A change point of six or fewer metastatic lymph nodes seems to carry prognostic significance, thus advocating for rigorous preoperative screening for nodal metastases.

The significance and the predictive factors of microscopic lymph node metastasis in patients with clinically node negative papillary thyroid cancer: A retrospective cohort study

BACKGROUND

The management of pathological lateral node involvement (pN1b) from papillary thyroid cancer (PTC) are controversial.

METHODS

A consecutive series of 246 patients, diagnosed with clinically node negative (cN0) PTC who had undergone surgery with prophylactic lateral node dissection, and without postoperative radioactive iodine administration from 2001 to 11, were reviewed to clarify the significance of pN1b.

RESULTS

Eighty-five (35%) patients had pN1b disease. One-half and 30% had pN1b in younger (age less than 45) and older patients (age 45 or over), respectively. Tumor size (≥ 21 mm) could predict pN1b disease in older patients. Patients with pN1b disease recurred more frequently (9 cases, 10.6%) than those without (4 cases, 2.4%), and 2 cases with pN1b died of the disease.

CONCLUSIONS

pN1b disease was commonly found in patients with PTC even when they were diagnosed clinically as node negative. pN1b disease with prognostic meaning was often found in the older patients with larger PTC indicating the necessity for adjuvant treatments.

MiR-9 and miR-21 as prognostic biomarkers for recurrence in papillary thyroid cancer

Despite low mortality rates, nodal recurrence in papillary thyroid carcinoma occurs in up to 20 % of patients. Emerging evidences indicate that dysregulated microRNAs are implicated in the process of metastasis. In the present study, we investigated whether miR-9, miR-10b, miR-21 and miR-146b levels are predictive of papillary thyroid carcinoma recurrence. Using macro-dissection followed by quantitative real-time PCR, we measured miR-9, miR-10b, miR-21 and miR-146b expression levels in formalin-fixed, paraffin-embedded samples of 66 patients with papillary thyroid carcinoma categorized into two groups: the recurrent group (n = 19) and the non-recurrent group (n = 47). All patients underwent total thyroidectomy and were followed for at least 120 months after surgery to be considered recurrence-free. Univariate and multivariate analysis were performed using the Cox proportional hazard model in order to identify associations between multiple clinical variables and microRNA expression levels and papillary thyroid carcinoma recurrence. MiR-9 and miR-21 expression levels were found to be significant prognostic factors for recurrence in patients with papillary thyroid carcinoma (HR = 1.48; 95 % CI 1.24-1.77, p < 0.001; and HR = 1.52; 95 % CI 1.18-1.94, p = 0.001; respectively). Multivariate analysis involving the expression level of miR-9 and miR-21 and various clinical parameters identified the expression of these microRNAs as independent prognostic factors for papillary thyroid cancer patients. In conclusion, our results support the potential clinical value of miR-9 and miR-21 as prognostic biomarkers for recurrence in papillary thyroid carcinoma.

Validation of the QTNM staging system for cancer-specific survival in patients with differentiated thyroid cancer

An Australian state database was used to test the validity of the Quantitative tumor/node/metastasis (QTNM) staging system for assessing prognosis of differentiated thyroid cancer (DTC) on the basis of four variables quantified at diagnosis (histopathology, age, node involvement, and tumor size). Using the Queensland Cancer Registry (QCR), we identified 788 cases of DTC diagnosed from 1982 to 2006 with complete staging information. Causes of death were ascertained by linking the QCR database with the Australian National Death Index. Subjects were staged according to AJCC TNM 7th edition and QTNM, and cancer-specific survival (CSS) was calculated by the Kaplan-Meier method. Cancer-specific mortality was observed in 22 (2.8 %) patients, with 10-year CSS for the cohort of 97.0 % at a median follow-up of 262.8 months. QTNM stage specific cancer survival at 10 years was 99.6, 97.0, and 78.6 % for low-, intermediate-, and high-risk groups, respectively. This was comparable to the original US dataset in which the QTNM was initially studied, and it fared better at discriminating survival than the standard TNM system, where there was overlap in survival between stages. The current study validates the QTNM system in an Australian cohort and shows at least equivalent discriminatory capacity to the current TNM staging system. The QTNM utilized prognostic variables of significance to produce an optimal three-stage stratification scheme. Given, its advantage in clearly discriminating between prognostic groups, clinical relevance and simplicity of use, we recommend that TNM be replaced with QTNM for risk stratification for both recurrence and CSS.

Therapeutic strategy for low-risk thyroid cancer in Kanaji Thyroid Hospital

It is well-known that differentiated thyroid carcinoma (DTC) has a generally indolent character and shows a favorable prognosis in comparison with many other carcinomas. The therapeutic strategy for patients with DTC in Japan has differed from that in Western countries. Total thyroidectomy followed by radioactive iodine (RAI) ablation has been standard in Western countries, whereas limited hemi-thyroidectomy and subtotal thyroidectomy has been extensively accepted in Japan. Papillary thyroid carcinoma (PTC) accounts for over 90% of all thyroid cancers in Japan. The majority of patients with PTC are categorized into a low-risk group on the basis of the recent risk-group classification schemes, and they show excellent outcomes. Several management guidelines for thyroid cancers have been published in Western countries. However, the optimal therapeutic options for PTC remain controversial, and high-level clinical evidence aimed at resolving these issues is lacking. Moreover, as socioeconomic differences in medical care exist, conventional policies for the treatment of PTC have differed between Japan and other countries. This review focuses on the special features of treatment in Japan for patients with low-risk DTC involving subtotal thyroidectomy without adjuvant therapies, rather than total thyroidectomy with RAI, with the aim of preserving quality of life. At our institution in Japan, we have had extensive experience with RAI treatment for high-risk DTC patients, and this represents a very rare situation. Here we introduce the therapeutic strategy for low-risk thyroid cancer in Japan, including the measures adopted at our institution.

Surgical complications and recurrence after central neck dissection in cN0 papillary thyroid carcinoma

OBJECTIVES

To evaluate surgical complications and recurrence patterns after central neck dissection (CND) in papillary thyroid carcinoma (PTC).

METHODS

A retrospective analysis was performed on 361 patients who underwent total thyroidectomy with or without CND for PTC from 2000 to 2007. Clinicopathological results and recurrence were stratified according to treatment modality.

RESULTS

Incidence of occult central metastasis of PTC was 64.3%. With respect to surgical morbidities, the total thyroidectomy (TT) with CND group exhibited a significantly higher incidence of transient vocal fold paralysis (10.0% vs 3.4%, p=0.029) and permanent hypocalcaemia (11.4% vs 4.5%, p=0.041), and significantly prolonged mean operating time (195.8min vs 153.0min, p<0.001) than the TT alone group. Analysis of the recurrence patterns revealed that level IV was most commonly involved in both groups. When the location of recurrence was categorised into central and lateral neck, the recurrence rate in the lateral neck was significantly higher than that in the central neck, regardless of initial CND.

CONCLUSIONS

CND was associated with permanent hypocalcaemia and transient vocal fold paralysis. The lateral neck was mainly involved in recurrence regardless of initial CND, suggesting the clinical benefit of CND may be small.

Preoperative subclinical hypothyroidism in patients with papillary thyroid carcinoma

OBJECTIVE

To assess the effect of preoperative subclinical hypothyroidism on prognosis and on the tumour's clinicopathological features at initial diagnosis of papillary thyroid carcinoma (PTC).

MATERIALS AND METHODS

328 patients who underwent surgery for PTC between January 2001 and December 2006 were enrolled in this study. Of these, we compared 35 patients with preoperative subclinical hypothyroidism with 257 patients who were euthyroid before the operation, with respect to clinicopathological characteristics and prognosis.

RESULTS

No significant differences were observed in tumour size, extrathyroidal extension, and multifocality between subclinical hypothyroidism and euthyroid patients. Patients with subclinical hypothyroidism had a considerably lower percentage of lymph node metastasis than did euthyroid patients (8.6% vs. 21.8%, p=0.068). Although preoperative subclinical hypothyroidism decreased the risk of lymph node metastasis at 0.313 of odds ratio in the multivariate analysis, its significance was not verified (95% confidence internal, 0.089-1.092; p=0.068). Patients with preoperative subclinical hypothyroidism tended to have a better prognosis than did preoperative euthyroid patients, for both recurrence (2.9% vs. 14.0%, p=0.099) and 7-year disease-free survival (97.1% vs. 87.8%, p=0.079), during the 82-month mean follow-up period. However, even as thyroid-stimulating hormone (TSH) concentration increased, there were no consistent relationships observed between the TSH levels and the prognostic parameters.

CONCLUSION

We could find neither a consistent positive nor a negative linear relationship between TSH levels and several prognostic parameters, indicating that subclinical hypothyroidism with elevated TSH is not an independent predictor of tumour aggressiveness and poor prognosis in PTC.

Pathological characteristics and clinical perspectives of papillary thyroid cancer: study of 714 patients

Papillary thyroid cancer belongs to most commonly diagnosed well-differentiated malignant tumor of the thyroid gland, with only minority of cases being more aggressive, recurring locoregionally and developing distant metastatic foci. The aim of this study was to determine the clinical relationship between parameters of age, gender, size of primary tumor, intraglandular dissemination and regional metastatic spread and evaluate the importance of each parameter; analyze other major aggressive factors (tumor border, thyroid capsule invasion, perivascular, perilymphatic spread) on prevalence and extent of intraglandular dissemination and relation to metastatic spread in neck. This study is a retrospective analysis of clinical and pathological data from 714 patients with papillary thyroid cancer, presented and operated at the Department of ENT/Head and Neck surgery, Sisters of Charity University Hospital, Zagreb, in the period from 1980 to 2008. All patients were operated upon with total thyroidectomy and some type of neck lymphonode dissection (paratracheal or lateral). In results, we found 46.9% tumors were aggressive; 34.7% tumors were multicentric, with foci in the contralateral lobe nearly twice as often as in the ipsilateral lobe; 27.8% were regionally metastatic, with equal distribution between paratracheal and lateral regions. In conclusion, we revealed contralateral lobe multicentricity and male gender as independent risk factors for regional metastatic dissemination. Nodular goiter has been identified as a protective parameter.

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.

A critical analysis of the American Joint Committee on Cancer (AJCC) staging system for differentiated thyroid carcinoma in young patients on the basis of the Surveillance, Epidemiology, and End Results (SEER) registry

BACKGROUND

Differentiated thyroid carcinomas (DTC) are the only tumors for which age is a determinant of stage in the American Joint Committee on Cancer's (AJCC) staging protocol. In this study, we re-examined the relationship between age, extent of disease, and prognosis by using a large dataset with longer follow-up times.

METHODS

We examined the Surveillance, Epidemiology, and End Results (SEER) registry data 1973 to 2005 for patients with DTC as their only known malignancy. We used Cox multivariate analyses to generate mortality hazard ratios, controlling for several variables, to evaluate the effects of age and disease extent.

RESULTS

We identified 55,402 patients with DTC. Of these, 49,240 had sufficient data to generate a TNM stage on the basis of AJCC guidelines. Within stage II, younger patients (<45 years) have worse outcomes than older patients (P < .001). Younger patients had an 11-fold increase in mortality between stages I and II, whereas there was no difference for older patients. When we uniformly applied the 45-and-older staging protocol to all patients, we found that stages III-IVc had a significantly greater risk of mortality for all patients compared with stage I.

CONCLUSION

The presence of regional and metastatic thyroid cancer bears prognostic significance for all ages. Under current AJCC guidelines, young patients with metastatic thyroid cancer may be understaged.

Surgical and pathological characteristics of papillary thyroid cancer in children and adolescents

Background. Thyroid carcinoma is a relatively rare pediatric pathology, comprising around 3% of all childhood tumors. We investigated parameters of tumor aggressiveness, multicentricity, and locoregional metastatic spread patterns in patients up to 18 years of age and made comparison with the older group. All patients were operated upon with total thyroidectomy, with or without lymph-node neck dissection. Results. Patients with papillary carcinoma present with more advanced stage, larger primary tumor, and more commonly present with palpable thyroid and/or neck node. Overall, papillary cancer demonstrated pathological aggressiveness as defined by our criteria in 60%, multicentricity in 40%, and locoregional metastatic foci in 77% of cases. Multicentric tumor foci in both thyroid lobes and tumor aggressiveness were identified as a risk factor for metastatic development. Conclusion. By observing clinicopathological parameters, we demonstrated that papillary thyroid cancer behaves more aggressively in the younger group. We recommend total thyroidectomy with careful intraoperative exploration of thyroid bed and lateral neck in search for possible metastatic spread. In case of positive findings, it is obligatory to perform a standard neck dissection, keeping in mind that neck lymphonodes are primary site of locoregional recurrence. With meticulous attention to technical aspects of operation, perioperative morbidity should be minimal.

Experience and analysis of level VII cervical lymph node metastases in patients with papillary thyroid carcinoma

PURPOSE

Papillary thyroid cancer with level VII (anterior superior mediastinal lymph nodes) lymph node metastasis belongs to Stage IV a according to the Americal Joint Committee on Cancer cancer staging. The aim of our study was to identify clinicopathologic factors that are related to level VII cervical lymph node metastasis and to suggest recommendations for level VII dissection.

METHODS

We reviewed 195 patients with papillary thyroid carcinoma who had their initial operation containing level VII dissection from April 2006 to June 2007. Level VII dissection involved lymph nodes in the anterior superior mediastinum and tracheoesophageal grooves, extending from the suprasternal notch to the innominate artery. Clinicophathologic factors, such as gender, age and lateral neck metastasis, related to Level VII metastasis were analyzed by tumor size, multifocality of tumor, extrathyroidal extension and lymphovascular invasion.

RESULTS

Nine (4.6%) of 195 patients with papillary thyroid carcinoma had level VII metastasis. Clinicopathologic factors that were related to level VII metastasis included lateral neck metastasis (P < 0.01), tumor size (P < 0.01) and lymphovascular invasion (P < 0.05).

CONCLUSION

If preoperatively, the tumor size is over 1.5 cm, or there is lateral neck metastasis, level VII dissection must be considered. If there is lymphovascular invasion pathologic findings postoperatively, special attention should be paid for detection of level VII recurrence.

Efficacy of preoperative neck ultrasound in the detection of cervical lymph node metastasis from thyroid cancer

OBJECTIVES/HYPOTHESIS

This study was performed to assess the diagnostic accuracy of surgeon-performed preoperative neck ultrasound (US) in the detection of both central and lateral cervical lymph node metastases from thyroid cancer.

STUDY DESIGN

Prospective cohort study.

METHODS

Data for all patients with thyroid cancers and follicular thyroid lesions who were evaluated by means of preoperative neck US were reviewed. The cervical lymph nodes were assessed for suspicion of metastasis based on US characteristics. The diagnostic accuracy of US was determined according to whether histologically confirmed cancer was present in surgical cervical lymph node specimens.

RESULTS

The sensitivity and specificity of US in predicting papillary thyroid carcinoma (PTC) metastasis in the central neck were 30.0% and 86.8%, respectively. The sensitivity and specificity of US in predicting metastasis in the lateral neck were 93.8% and 80.0%, respectively. A subset of patients underwent US followed by revision neck dissection for PTC, and the sensitivity and specificity of US in predicting metastasis in the lateral neck were 100% and 100%, respectively.

CONCLUSIONS

Preoperative neck US is a valuable tool in assessing patients with thyroid cancers. The highly sensitive and specific nature of US in predicting cervical lymph node metastasis in the lateral neck, especially in the setting of recurrent disease, can provide reliable information to assist in surgical management. Although US for central compartment lymphadenopathy in the presence of the thyroid gland is less sensitive and specific than US for the lateral neck, it still provides useful information that can be obtained at the same time the primary thyroid pathology is assessed.

Thyroidectomy and lymph node dissection in papillary thyroid carcinoma

Papillary carcinoma is a prominent malignancy originating from follicular cells. This disease generally shows an indolent character, but patients demonstrating certain clinicopathological features have a dire prognosis. At present, Western countries adopted almost routine total thyroidectomy with radioactive iodine (RAI) ablation, while limited thyroidectomy with extensive prophylactic lymph node dissection has traditionally been performed for most patients in Japan. Recently, accurate evaluation of carcinoma stage can be performed on preoperative imaging studies, especially on ultrasonography. It is therefore important to treat papillary carcinoma patients depending on clinicopathological features rather than in a stereotyped fashion. In this paper, appropriate extension of thyroidectomy and lymph node dissection is discussed based on Western and recently published Japanese guidelines and the experience in Kuma Hospital.

Surgical management of cervical lymph nodes in differentiated thyroid cancer

Well-differentiated thyroid cancer (DTC) carries an excellent prognosis. Although long-term survival rates are high, regional lymph node metastases are common. Surgical management of cervical lymph nodes is integral to the comprehensive treatment of DTC, but data from large randomized trials do not exist to define optimal treatment. Therapy is thus guided by observational data, and founded on an understanding of the behavior of lymphatic metastases in DTC. This article focuses on the significance of lymph node metastases in thyroid cancer, and the strategy for surgical management.

Impact of prophylactic central neck lymph node dissection on early recurrence in papillary thyroid carcinoma

BACKGROUND

Although the role of prophylactic central neck lymph node dissection (CNLD) in the treatment of papillary thyroid carcinoma (PTC) is controversial, many surgeons perform routine prophylactic CNLD. The present study compares local recurrence rates in PTC patients undergoing total thyroidectomy with and without prophylactic CNLD.

MATERIALS AND METHODS

A retrospective review of 206 patients undergoing thyroidectomy for PTC was conducted at two tertiary referral centers. Of these, 81 patients had total thyroidectomy for PTC and a follow-up between 2 and 9 years with a mean of 3.1 years. Of these 81 patients, 45 underwent routine prophylactic CNLD and 36 did not. For those two groups, demographics, clinical and pathologic findings, radioactive iodine (RAI) treatment, and the incidence of recurrence were compared. Univariate statistical analysis was performed.

RESULTS

There was no significant difference in age, gender, multifocality, or extrathyroidal extension for the two groups. Patients with CNLD had an average tumor size of 1.4 cm versus 2 cm in the group without CNLD (p < 0.05). Patients who underwent CNLD had an average of 8 nodes removed, and positive nodes were found in 33%. Patients with CNLD received a higher dose of RAI, 102.7 mCi versus 66.3 mCi (p < 0.05). The incidence of positive nodes correlated with an increased RAI dose (r = 0.55). Rates of parathyroid removal and autotransplantation were higher in the CNLD group, 36 and 16% in the CNLD group versus 22 and 3% in the group without CNLD (p = 0.4 and p = 0.07). Rates of temporary hypocalcemia were higher in the CNLD group (31 versus 5%; p = 0.001), however rates of permanent hypocalcemia were similar, 1/35 in the no CNLD group versus 0/45 in the CNLD group (p = 0.4). There was a higher recurrence rate among patients without CNLD 6/36 (16.7%) versus 2/45 (4.4%), although this difference was not statistically significant (p = 0.13).

CONCLUSIONS

Routine CNLD as an adjunct to total thyroidectomy identifies positive nodes in over 30% of patients with PTC. The discovery of positive nodes is associated with higher doses of RAI for postoperative ablation, and there is a trend toward decreased recurrence in patients undergoing CNLD.

Ipsilateral versus bilateral central neck lymph node dissection in papillary thyroid carcinoma

OBJECTIVE

Many patients undergoing thyroidectomy for papillary thyroid carcinoma (PTC) have subclinical nodal disease at the time of surgery. Prophylactic bilateral central neck dissection (CND) is gaining acceptance in the treatment of PTC as studies have shown nodal disease increases the rate of local recurrence and may alter postsurgical radioactive iodine dosing. Given the potential complications of bilateral CND, we undertook a prospective study to determine the adequacy of prophylactic ipsilateral CND for PTC.

METHODS

A total of 116 patients with PTC underwent total thyroidectomy and routine prophylactic CND at a tertiary referral center. Of these, 45 had right and left central neck lymph node basins submitted separately for pathologic examination. We examined the laterality of positive lymph nodes based on tumor location and size.

RESULTS

Overall, positive lymph nodes were found in 45% of patients. Of the patients having a lateralized CND, 33% had ipsilateral positive nodes only, while 20% had bilateral positive nodes. None of the patients with tumor size <=1 cm had bilateral positive lymph nodes compared with 31% of patients with tumors >1 cm (P = 0.02). Multifocality did not affect lymph node metastasis in tumors <=1 cm. Parathyroids were found in the pathology specimen of 34% of patients, 40% had parathyroids autotransplanted, 47% had temporary hypocalcemia, and 0% had permanent hypocalcemia. Rates of temporary and permanent recurrent laryngeal nerve injury were 5% and 0% respectively.

CONCLUSIONS

Ipsilateral CND appears to be sufficient in patients with tumors <=1 cm. In tumors >1 cm, bilateral CND should be considered as these patients are more likely to have bilateral positive nodes. If tumor size is used as criteria for prophylactic CND, approximately one-third of patients can be spared a bilateral CND.

Simplifying the TNM System for Clinical Use in Differentiated Thyroid Cancer

Purpose

The TNM stratification has been found useful at stratifying patients with differentiated thyroid carcinoma (DTC) into prognostic risk groups. However, it is cumbersome to implement clinically given the large number of bins within this system and the complicated system of arriving at stage information.

Patients and Methods

We decided to quantify each variable in this system to arrive at a simplified quantitative alternative to the TNM system (QTNM) and compare this with the conventional system. We used our electronic record system to identify 614 cases of DTC managed at our institution from 1987 to 2006. Cancer-specific survival (CSS) and disease-free survival (DFS) were calculated by the Kaplan-Meier method, and a simplified QTNM score was devised using a Cox proportional hazards model.

Results

We were able to quantify the TNM system as follows: 4 points each for age older than 45 years and presence of neck nodal metastases while 6 points for tumor size larger than 4 cm or extrathyroidal extension and 1 point for nonpapillary DTC. A sum of 0 to 5 points was low risk, 6 to 10 points intermediate, and 11 to 15 points high risk. Comparison with the conventional TNM system and two other systems revealed similar or better discrimination with the QTNM and this discrimination was maintained when this risk stratification was applied to a unique validation set.

Conclusion

The QTNM system as opposed to the conventional TNM system seems to be a simple and effective method for risk stratification for both recurrence and cancer-specific mortality.

Management of regional metastases in well-differentiated thyroid cancer

Thyroid cancer represents the most common endocrine cancer, and rates have been increasing over the last 3 decades. The treatment of cervical metastases in well differentiated thyroid cancer remains in evolution. Many questions require further resolution. Unlike many other malignancies, most large studies have found that overall survival is not significantly affected by regional metastases. On the other hand, several studies have noted that regional disease may decrease survival in selected patient groups. The greatest effect of lymph node metastases seems to be an increase in recurrence rates. Except for the compartment-oriented removal of clinically positive nodes, few strong recommendations may be made.

[Usefulness of ultrasound in the diagnosis and management of well-differentiated thyroid carcinoma]

Thyroid nodules are found in the vast majority of the population, but only 5 to 10% are malignant. Ultrasonography of the thyroid, by virtue of being a straightforward, non-invasive method presenting strong correlation with macroscopic aspects of the thyroid gland, is being increasingly used to identify nodules that present a higher risk of malignancy. The presence of certain ultrasonographic characteristics such as hypoechogenicity, microcalcifications, irregular contours and central vascularization on Doppler, increase the risk of the lesion being malignant. Conversely, nodules presenting benign ultrasonographic characteristics such as hyperechogenicity and a mixed sponge-like aspect, and a concordant cytology, have a negative predictive value of 96.6%. It is, thus, important to examine all nodular lesions and to identify suspicious lesions that need biopsy, especially in multinodular glands. Ultrasonography is also highly sensitive in the identification of suspicious cervical lymph nodes during the follow-up of patients with thyroid carcinoma, even when PCI is negative and serum thyroglobulin (Tg) levels are undetectable. Tg measurement in the needle wash-out content is recommended as this has proven to be more sensitive than cytology in the diagnosis of cervical metastasis, especially where there is liquid content, and it is not affected by the presence of anti-Tg antibodies.

Central Lymph Node Dissection in Differentiated Thyroid Cancer

BACKGROUND

There has been renewed interest in extensive lymph node dissection for papillary thyroid cancer (PTC), and a number of reports have been published concerning compartment-oriented dissection of regional lymph nodes in PTC. A comprehensive review of this body of literature using evidence-based methodology is pending.

METHODS

Systematic review of the literature using evidence-based criteria.

RESULTS

Issue 1: Systematic compartment-oriented central lymph node dissection (CLND) may decrease recurrence of PTC (Levels IV and V data, no recommendation) and likely improves disease-specific survival (grade C recommendation). Limited level III data suggest survival benefit with the addition of prophylactic dissection to thyroidectomy (grade C recommendation). The addition of CLND to total thyroidectomy can significantly reduce levels of serum thyroglobulin and increase rates of athyroglobulinemia (level IV data, no recommendation). Issue 2: There may be a higher rate of permanent hypoparathyroidism and unintentional permanent nerve injury when CLND is performed with total thyroidectomy than for total thyroidectomy alone (grade C recommendation). Issue 3: Reoperation in the central neck compartment for recurrent PTC may increase the risk of hypoparathyroidism and unintentional nerve injury when compared with total thyroidectomy with or without CLND (grade C recommendation), supporting a more aggressive initial operation.

CONCLUSION

Evidence-based recommendations support CLND for PTC in patients under the care of experienced endocrine surgeons.

Lateral and Mediastinal Lymph Node Dissection in Differentiated Thyroid Carcinoma: Indications, Benefits, and Risks

BACKGROUND

There are 3 compartments of regional lymph nodes to which thyroid carcinoma metastasizes: central, lateral, and mediastinal compartments. The central compartment is the nearest to the thyroid and usually dissected routinely. However, the indication for dissection of the lateral and mediastinal compartments for differentiated thyroid carcinoma remains an open question.

METHODS

The indication for dissection of lateral and mediastinal compartments is evaluated based on previous reports, including those from our department.

RESULTS

There is nothing controversial about the indication for therapeutic lateral node dissection for tumors with clinically apparent lateral node metastasis. Such cases are more likely to show recurrence, especially in previously dissected compartments, and surgeons must perform dissection carefully. Although there are no randomized studies on the indication for prophylactic lateral node dissection, it is recommended for papillary carcinoma with aggressive characteristics such as large size and massive extrathyroid extension. Prophylactic mediastinal dissection via median sternotomy is not recommended.

CONCLUSIONS

Node dissection of the lateral and mediastinal compartments must be performed aggressively and radically to prevent recurrence in previously dissected regions.

Nodal yield, morbidity, and recurrence after central neck dissection for papillary thyroid carcinoma

BACKGROUND

The role of central neck dissection (CND) in differentiated thyroid cancer remains controversial. This study aims at elucidating the potential benefits and drawbacks of CND associated to total thyroidectomy in papillary cancer.

METHODS

Protocols of patients undergoing total thyroidectomy and CND for papillary cancer were reviewed. The following data were recorded: macroscopic appearance of central nodes; nodes obtained at operation; number of metastatic nodes and parathyroid glands incidentally resected; metastases, age, completeness, invasiveness, size score; postoperative s-Ca; complications; and recurrences. Differences between therapeutic (gross nodal involvement) and prophylactic (no apparent node involvement) CNDs were studied.

RESULTS

Forty-three patients (mean age, 52 +/- 17 years) were studied. A mean of 8.4 +/- 6.6 nodes were resected per patient. A 60% prevalence (26/43) of presence of nodal involvement (N+) was found with no difference between low- and high-risk patients. Twenty-five (60%) patients developed transient hypocalcemia, which was associated with incidental parathyroidectomy, number of nodes resected, and thymectomy. Two patients (4.6%) developed permanent hypoparathyroidism and 3 (7%), transient vocal cord paralysis. Parathyroid glands were found in 19% of the specimens. At follow-up, there were no central neck recurrences, but 5 patients developed lateral recurrences despite treatment with I(131). All 5 patients had had therapeutic CND with 6 or more metastatic nodes obtained in the CND specimen. No lateral neck recurrences were observed after prophylactic CND or in patients with < 6 nodes involved.

CONCLUSIONS

CND prevents central neck recurrences. Morbidity of bilateral CND is significant, and its systematic implementation in the absence on gross nodal involvement requires reassessment.

Detection and surgical treatment of cervical lymph nodes in differentiated thyroid cancer

There is considerable controversy regarding the treatment of patients with cervical metastases from differentiated thyroid cancer. Most have papillary carcinoma and the main areas of contention relate to methods of assessment and staging, surgical management and mode of follow up. there is little evidence to support elective anatomical imaging with CT or MRI in those patients with suspected or proven malignancy at the primary site as indicated by fine needle aspiration cytology (FNAC) but who have no clinical evidence of nodal disease. The role of routine ultrasound (US) in the pre-operative assessment of suspected or known malignancy is developing but is largely unproven. When it is performed, high risk areas for metastatic neck disease (levels II-V) should be assessed. Suspicious nodes on US should be further evaluated by FNAC. Suspected or proven neck disease may be further assessed pre-operatively with CT or MRI and then treated surgically. Disease in the central compartment requires a total thyroidectomy and level VI central compartment neck dissection. Suspected or proven lateral compartment cancer should be treated by selective neck dissection (at least levels III, IV, and V) below the accessory nerve. There is no role for 'Berry picking' and clinically node negative high risk patients should have an elective central compartment level VI neck dissection. Sentinel node biopsy lays no role and neither does elective lateral compartment surgery in patients with no clinical or radiological evidence of disease. For follow up, US represents the most sensitive means of detecting neck recurrences and in the presence of an elevated serum thyroglobulin, imaging may also include whole body iodine-131 scanning and anatomical imaging with CT or MRI. The role of PET remains controversial but is likely to develop further as the technique becomes more widely available. In the future, the concentration of patients with this disease in large center can only improve the way we treat differentiated thyroid cancer.

Retrospective analysis of predictive factors for recurrence after curatively resected papillary thyroid carcinoma

PURPOSE

This retrospective study analyzes the predictive factors after curative surgery for papillary thyroid carcinoma (PTC).

METHODS

We analyzed 386 patients who underwent a curative operation for PTC in our hospital between 1977 and 1997, subject to the inclusion criteria.

RESULTS

According to univariate analysis, pathological lateral cervical lymph node involvement (P < 0.0001), dedifferentiation of the tumor (P < 0.002), male sex (P < 0.0001), a large tumor (P < 0.005), and an age of over 50 years (P < 0.05) were significant factors. Cox's proportional hazard model showed that a man (P < 0.05), aged over 50 years (P < 0.05), who had a large primary tumor (P < 0.05) with dedifferentiation (P < 0.05), and pathological lateral cervical lymph node metastasis (P < 0.005) was more likely to have recurrence of PTC.

CONCLUSIONS

Determining whether lymph node metastasis exists could be useful for predicting recurrence in patients who have undergone curative resection of PTC.

[Lymph node dissection in non-medullary differentiated thyroid carcinoma]

Papillary and follicular thyroid carcinomas are the most common form of endocrine carcinomas. Lymph node involvement seems to be a low risk factor for death, but it increases the risk for loco-regional recurrences and distant metastasis. The limits and the key points of the cervical lymph node dissection are described. The sentinel lymph node is used to rarely, so it could limit the lymph dissection. Node-picking has to be avoided. Central lymph node resection is recommended for high-risk patients, as male, patients more than 45 or less than 21 years old, papillary carcinomas greater than 1 cm or follicular carcinoma more than 2 cm in diameter. Lateral lymph node resection is performed when the lymph nodes of the central compartment are involved, more than 3 cm in diameter, and bulked. Prophylactic lymphadenectomy is useless. When thyroid carcinoma is known postoperatively, re-operation depends of the cervical mass and of the results of the radioactive iodine treatment.

What the clinician wants to know: surgical perspective and ultrasound for lymph node imaging of the neck

Imaging of lymph node metastases in the neck can have two major indications: (1) prognosis and assisting with choice of treatment; (2) staging and detection of clinically occult metastases in different levels of the neck. Both indications are discussed. The role and limitations of US and US-guided fine-needle aspiration cytology are also reviewed.

Prognostic factors for persistent or recurrent disease of papillary thyroid carcinoma with neck lymph node metastases and/or tumor extension beyond the thyroid capsule at initial diagnosis

CONTEXT

Reliable prognostic factors are needed in papillary thyroid cancer patients to adapt initial therapy and follow-up schemes to the risks of persistent and recurrent disease. OBJECTIVE AND SETTINGS: To evaluate the respective prognostic impact of the extent of lymph node (LN) involvement and tumor extension beyond the thyroid capsule, we studied a group of 148 consecutive papillary thyroid cancer patients with LN metastases and/or extrathyroidal tumor extension. Initial treatment, performed at the Institut Gustave Roussy between 1987 and 1997, included in all patients a total thyroidectomy with central and ipsilateral en bloc neck dissection followed by radioactive iodine ablation.

RESULTS

Uptake outside the thyroid bed, demonstrating persistent disease, was found on the postablation total body scan (TBS) in 22% of the patients. With a mean follow-up of 8 yr, eight patients (7%) with a normal postablation TBS experienced a recurrence. Ten-year disease-specific survival rate was 99% (confidence interval, 97-100%). Significant risk factors for persistent disease included the numbers of LN metastases (>10) and LN metastases with extracapsular extension (ECE-LN >3), tumor size (>4 cm), and LN metastases location (central). Significant risk factors for recurrent disease included the numbers of LN metastases (>10), ECE-LN (>3), and thyroglobulin level measured 6-12 months after initial treatment after T4 withdrawal.

CONCLUSION

We highlight an excellent survival rate and suggest risk classifications of persistent and recurrent disease based on the numbers of LN metastases and ECE-LN, LN metastases location, tumor size, and thyroglobulin level.

A less invasive, selective, functional neck dissection for papillary thyroid carcinoma

HYPOTHESIS

To describe an alternative lateral neck access in order to perform neck dissection in papillary thyroid carcinoma (PTC) with lymph node involvement.

DESIGN

Prospective (January 2000 to December 2003), 36-month study.

SETTING

Catholic University of Rome and University of "Tor Vergata", Rome, Italy.

PATIENTS AND METHODS

Twenty-four consecutive patients with PTC and cervical lymph node metastases were included. Functional neck dissection (FND), unilateral or bilateral, was performed acceding via a lateral dissection through a traditional Kocher incision, running along the superficial fascia of the neck and posteriorly to the sternocleidomastoideus muscle.

RESULTS

Mean age was 39.04+/-13.69 years. Twenty patients were women and four were men. Mean tumour size was 2.5+/-1 cm, while the greatest metastatic lymph node size was 4.5 cm. Minimally invasive, selective FND was performed in all patients associated to total thyroidectomy and central compartment lymph node clearance. Metastatic lymph nodes were found in 142 out of 340 of the lymph nodes dissected.

CONCLUSIONS

Minimally invasive neck dissection seems to carry a lower risk in terms of specific morbidity and allows a quicker recovery and a better aesthetic result. This access has to be considered as a less invasive procedure compared to the other surgical accesses for the radical or modified lateral neck dissection.

Resection and replacement of the carotid artery in metastatic head and neck cancer: literature review and case report

Metastases of advanced tumours of the oral cavity sometimes affect the cervical segments of the carotid arteries. The situation is worse in the 5-10% of cases in which the metastasis involves the common or internal carotid to such an extent that resection and replacement of the artery become necessary. Following clinical, CT/NM, and angiographic examinations, a surgical plan for the resection and reconstruction of the affected vascular segment is formulated. In preparing a treatment plan, emphasis must be placed on the expected quality of life, and careful consideration must be given to the extent of the operation.A survey of the international literature reveals that the reported mean 1-year complaint free survival rate after resection and reconstruction varies between 0 and 44%. In our experience, the wall of the carotid vessels is very resistant to tumour invasion in a large majority of patients. When radical surgery and reconstruction are carried out in the same session, does this increase the long-term cure rate and lengthen patient survival? A number of authors agree that radical interventions do not alter the survival indices significantly, but may improve the quality of life and regional control of the disease. The controversy over this topic is illustrated by means of a case report.

[Thyroid cancer: prognostic factors and treatment]

Because most differentiated thyroid carcinomas have an excellent prognosis, some authors have claimed that these patients are suffering from over treatment. Grouping patient- and tumor-specific factors have been proposed for prognostic stratification, but no clinicopathologic staging was demonstrated to be useful at the present time. More recently, molecular genetic tools have been used to identify and understand how the primary tumor progresses and many molecular markers have been proposed in order to distinguish the subset of patients at risk of developing metastasis. Here we analyzed some of them, with emphasis on the expression of NIS, a determinant of prognosis since the functional integrity of the iodine transport is essential to assure an uptake of radioiodine high enough to detect and destroy any tumoral thyroid tissue. More recent observations on how some relevant molecular genetics aspects of thyroid cancer impact new potential therapeutic approaches are also discussed.

Greater Local Recurrence Occurs with “Berry Picking” than Neck Dissection in Thyroid Cancer

Managing cervical lymph node metastases in well-differentiated thyroid cancer with either “berry picking” (BP) or anatomic neck dissection (AND) has not been shown to alter survival. Nevertheless local control of thyroid cancer is important. The purpose of this study is to determine whether the local recurrence rate of well-differentiated thyroid cancer is equivalent with BP versus AND. A retrospective analysis revealed 41 patients with well-differentiated thyroid cancer and cervical node metastases seen by a single surgeon from 1985 to 2002. A total of 83 initial and repeat neck operations were performed (nine BPs, 30 central neck dissections, and 44 modified radical neck dissections). Recurrence of cancer, intervention for recurrence, and complications of the BP and AND groups were evaluated. All nine (100%) patients undergoing a limited BP operation had local recurrence of cancer. Only three of the 32 (9%) patients undergoing an initial formal neck operation had local recurrence of tumor. The recurrences after BP (100%) were significantly greater than the recurrences after AND (9%) ( P < 0.001). The incidence of surgical complications with BP and AND was not different. Six of 32 (19%) initial formal neck dissection patients and four of nine (44%) BP patients had surgical complications. We conclude that BP is associated with greater local recurrence of thyroid cancer. Patients with nodal metastases should be managed with ANDs.

Well-differentiated carcinoma of the thyroid

Thyroid cancer will be diagnosed in more than 20,000 individuals in the United States in 2002. Approximately 16,000 of these patients will be women. During the same year, an estimated 1300 deaths from thyroid cancer are expected. The various types of thyroid cancer include papillary carcinoma, follicular carcinoma, Hurthle cell carcinoma, medullary carcinoma, anaplastic carcinoma, and thyroid lymphoma. Papillary, follicular, and Hurthle cell carcinoma are considered well-differentiated thyroid cancers and constitute the focus of this article.

Sentinel lymph node dissection for thyroid malignancy

Sentinel lymph node dissection (SLND) for melanoma and breast cancer has been validated as an accurate technique to assess the status of the lymph nodes in the regional drainage basin. The sentinel node concept has also been investigated in other solid tumors, and more recently, in thyroid carcinoma. SLND using a vital blue dye during thyroidectomy for suspected thyroid malignancy successfully identifies sentinel nodes, with minimal morbidity. Excised sentinel nodes can be examined for micrometastases, and if negative, then the rest of the cervical nodes are likely to be negative. The false negative rate of SLND for thyroid malignancy is unknown, however, because modified neck dissections have not accompanied all cases. The impact that lymph node metastasis in thyroid carcinoma has on prognosis is debatable, unlike breast cancer and melanoma, which therefore makes the utility of thyroid SLND less clear. The technique, results, and morbidity of SLND during thyroidectomy is presented, and its possible utility in well-differentiated and medullary thyroid carcinoma is discussed.