Minimal Extrathyroidal Extension Research Articles

Occult invasion of sternothyroid muscle by differentiated thyroid cancer.

To determine the incidence of occult invasion of sternothyroid by differentiated thyroid cancer (DTC) and identify clinico-pathological features associated with the same. Retrospective study of a consecutive series of DTC patients undergoing surgery, with preoperative ultrasound showing no evidence of strap muscle invasion. All had en bloc excision of sternothyroid muscle along with thyroidectomy. Incidence of microscopic invasion of sternothyroid and clinicopathologic features associated with the same, were studied. A total of 76 patients with DTC (2010-2014) were identified, of whom 62 met the inclusion criteria and were included in this study. Of these, 22 (36%) had no extrathyroidal extension (ETE), 30 (48%) had minimal ETE without sternothyroid invasion and 10 (16%) had minimal ETE with microscopic sternothyroid invasion. The mean tumor sizes of the three sub-groups were 1.9, 3.1 and 4.9cm, respectively, with a significant difference between no ETE and sternothyroid invaded sub-groups (p = 0.03). Out of the 40 cases with minimal ETE, 3 (7.5%) had positive tumor microscopic margin. Retaining sternothyroid in situ would have theoretically increased this proportion to 27.5%. Over a median follow-up of 52 months, 58 (94%) patients remained structurally disease free, with only 1 local recurrence. Occult invasion of sternothyroid muscle occurred in 16% of DTC in this series. Excision of the muscle en bloc with thyroidectomy, particularly in larger tumors, may confer benefit in accurately staging the disease, encompassing occult ETE and achieving clear microscopic margins.

Diagnostic value of combination of US and MRI in preoperative prediction for the extrathyroidal extension of papillary thyroid carcinoma

Objective: The purpose of the present study was to evaluate the diagnostic performance of preoperative ultrasonography(US), magnetic resonance imaging(MRI) and US combined with MRI in the prediction of extrathyroidal extension(ETE) in patients with papillary thyroid carcinoma(PTC). Methods: Between January 2013 and December 2016, a total of 83 consecutive patients underwent surgery for pathologically confirmed PTCs with ETE. We analyzed all patients with PTC with ETE who received preoperative combination of US and MRI scan to evaluate ETE. Results: For minimal ETE, the accuracy was 92.2%(47/51) of US, 74.5%(38/51) of MRI, and their combination was 98.0%(50/51). The differences of the three methods for minimal ETE were statistically significantly different(P=0.000). For extensive ETE, the accuracy was 62.5%(20/32) of US, 87.5%(28/32) of MRI, and their combination was 93.8%(30/32). The different of the three methods for extensive ETE was statistically significantly different(P=0.000). For the total accuracy of ETE, US was 80.7%(67/83), MRI was 79.5% (66/83), and their combination was 96.4%(80/83). The difference of the three methods for ETE was statistically significantly different(P=0.001). Conclusion: The combination of US and MRI can improve the preoperative diagnostic accuracy of ETE for PTC.

Impact of major different variants of papillary thyroid microcarcinoma on the clinicopathological characteristics: the study of 1041 cases

BackgroundThe incidence of papillary thyroid microcarcinoma (PTMC) has been increasing globally in the past few decades. PTMC does not have a distinctive morphology that results in differences in biological behavior. The aim of this study was to classify PTMCs according to the morphological features and explore the relationship with clinicopathological characteristics. Additionally, we sought to evaluate whether different variants of PTMC can be an independent predictor for lymph mode metastasis when considering other risk factors.MethodsBetween December 2014 and December 2015, 1041 PTMC cases undergoing surgical resection at Tianjin Medical University Cancer Institute and Hospital were reviewed retrospectively. Statistical analysis was performed to investigate the independent factors for lymph node metastasis in PTMC.ResultsConventional variant PTMC (CPTMC), follicular variant PTMC (FPTMC), and encapsulated variant PTMC (EnPTMC) were major variants in PTMC, collectively accounting for 96.7% of the entire PTMC cohort.There were significant differences in clinicopathological characteristics among the three major variants. The frequency of aggressive parameters was significantly different among the three variants, including tumor size, minimal extrathyroidal extension (minimal ETE), and lymph node metastasis (all P < 0.05), being highest in CPTMC, lowest in EnPTMC, and intermediate in FPTMC. FPTMC (OR = 0.642, P = 0.003) and EnPTMC (OR = 0.540, P = 0.041) were independent protective factors for lymph node metastasis (LNM). In contrast, male gender (OR = 1.836, P = 0.000), age less than 45 years (OR = 1.457, P = 0.009), tumor size greater than 0.5 cm (OR = 1.453, P = 0.007), calcification (OR = 1.465, P = 0.016), minimal ETE (OR = 1.801, P = 0.001), and multifocality (OR = 1.721, P = 0.000) were independent risk factors for LNM.ConclusionsThe present study demonstrates the distinct biological behaviors of the three major PTMC variants and establishes an aggressive order of CPTMC ≫ FPTMC > EnPTMC. It is necessary to take into consideration variant-related risks and other independent predictors for the determination of lymphadenectomy in patients with PTMC.

Influence of tumor extent on central lymph node metastasis in solitary papillary thyroid microcarcinomas: a retrospective study of 1092 patients

BackgroundThe morbidity of papillary thyroid microcarcinomas is increasing worldwide. Surgery is the main treatment for papillary thyroid microcarcinomas, and the choice of surgical method partly depends on the T stage of the tumor. However, according to the American Joint Commission on Cancer staging system (7th edition), the T stage of papillary thyroid microcarcinomas with different tumor extent is unclear. We aimed to study the effect of tumor extent and other factors on central lymph node metastasis to explore the relationship between tumor extent and T stage and to identify the risk factors predicting central lymph node metastasis in papillary thyroid microcarcinomas.MethodsWe included 1092 patients diagnosed with solitary papillary thyroid microcarcinomas between July 2011 and April 2016. The tumor extent and other central lymph node metastasis risk factors were retrospectively analyzed.ResultsUnivariate analysis revealed that capsule invasion and extracapsular extension (P = 0.013, <0.001; respectively) were significantly correlated with central lymph node metastasis. On multivariate analysis, extracapsular extension was independent central lymph node metastasis predictors (odds ratio 3.092, 95% CI 1.744–5.484), while capsule invasion was not (odds ratio 1.212, 95% CI 0.890–1.651). In addition, multivariate analysis revealed that male sex, tumor size >5 mm, and age <45 years were independent central lymph node metastasis predictors (odds ratio 2.072, 2.356, 2.302; 95% CI 1.483–2.894, 1.792–3.099, 1.748–3.031; respectively).ConclusionsThis study supported that capsule invasion and tumor limited to the thyroid in papillary thyroid microcarcinomas were suitable for the lower T1, that is, capsule invasion in papillary thyroid microcarcinomas might not belong to the minimal extrathyroid extension included in T3 of TNM staging. In addition, patients with risk factors of extrathyroid extension, male sex, age <45 years, or tumor size >5 mm in papillary thyroid microcarcinomas should consider a more aggressive surgical treatment.

Is postoperative radioactive iodine associated with a survival advantage among…

Abstract Aim This trial aimed to determine wether postoperative radioactive iodine(RAI) associated with a survival benefit among intermediate-risk Papillary Thyroid Cancer patients or not. Methods this study is a retrospective study of intermediate-risk papillary thyroid cancer patients that were treated with or without post operative RAI from 1st January 2002 till 1st January 2012. Overall survival (OS) and multivariate regression analyses were measured for all patients. Results 100 patients were included in this trial : 70 patients received postoperative RAI and 30 patients did not. The mean follow-up time was 7.1 (4.8 -15.1 years), and a median survival time could not be estimated. Overall survival at 10 years was 96% in the RAI vs 93% in the group without RAI (P &lt; .001). RAI reduced risk of death by a 27% [hazard risk (HR) 0.73, confidence interval (CI) 0.64 - 0.84, P &lt; .001]. Older patient age, male gende, larger tumor size, multifocal tumors, lymph node metastases, aggressive histology, vascular invasion, positive surgical margin, minimal extrathyroidal extension and absence of postoperative RAI were accompanied by compromised OS (all P ≤ .001). Conclusion This representative study addresses the survival advantage of RAI for with intermediate risk PTC patients but conducting of large prospective randomized controlled trial is still warranted.

Minimal extrathyroidal extension does not affect survival of well-differentiated thyroid cancer.

Differentiated thyroid cancer (DTC) with minimal extrathyroidal extension (MEE) is classified as stage III regardless of the tumor size. In this study, we aim to examine the effect of MEE on the overall survival and management of this population. A retrospective cohort study was performed, which utilized the National Cancer Database (NCDB), 2004-2012. The study population included patients, aged ≥ 45 years, who underwent surgery for DTC (pT3N0M0) with MEE compared to that in patients with pT2N0M0. A total of 9556 patients were included. These were divided into four groups, 4410 patients with pT2N0M0 (Group 1: T ≤ 4 cm without MEE), 3274 with pT3N0M0 (Group 2: T ≤ 4 cm with MEE), 447 with pT3N0M0 (Group 3: T > 4 cm with MEE) and 1430 patients with pT3N0M0 without MEE (Group 4: T > 4 cm without MEE). Median follow-up time was 46.7 months (interquartile range: 27.8-72.1). Patients in Group 2 (T ≤ 4 cm with MEE) had no significant worse survival compared to patients in Group 1 (T ≤ 4 cm without MEE) (P = 0.85), whereas Groups 3 and 4 (T > 4 cm), both had significantly lower survival (P < 0.001) with no difference between the two groups. Total thyroidectomy was associated with improved overall survival compared to that in lobectomy in Group 4 (T > 4 cm without MEE). Radioiodine utilization was associated with improved survival only with tumors larger than 4 cm with or without MEE. In DTC patients aged older than 45 years of age with tumor size less than 4 cm, MEE has no survival significance. Tumor size is an independent prognostic marker regardless of MEE status. Our data support re-evaluation of the current staging system.

Prognostic impact of minimal extrathyroidal extension in papillary thyroid carcinoma.

It is widely accepted that maximal extrathyroidal extension (ETE) plays a vital role in the prognosis of papillary thyroid carcinoma (PTC). However, there is no consensus among researchers about the meaning of minimal ETE (mETE) in PTC. Herein, we conducted a systematic review and meta-analysis to examine the role of mETE in the prognosis of PTC. We searched PubMed, EMBASE, and Cochrane search trials databases in English to identify studies comparing data on disease recurrence in PTC patients with mETE and those with no ETE. To summarize the data related to mETE status, risk ratios and hazard ratios adjusted for potential confounders were used to assess the number of recurrence and time-dependent risks related to mETE status, respectively. According to the inclusion criteria, a total of 7951 patients from 9 studies were included. The recurrence rate in patients with mETE is significantly higher when compared with those with no ETE (risk ratio = 1.70, 95% confidence interval: 1.26-2.28, I = 56%). According to the data summarized with hazard ratios, PTC patients with mETE showed a significantly increased risk of disease recurrence. mETE is a risk factor for poor prognosis in patients with PTC. Our innovative classification of ETE has its value in assessing the prognosis of PTC.

Extrathyroidal Extension Is Associated with Compromised Survival in Patients with Thyroid Cancer.

Patients with thyroid cancer who have extrathyroidal extension (ETE) are considered to have more advanced tumors. However, data on the impact of ETE on patient outcomes remain limited. The purpose of this study was to evaluate the association between ETE and survival in patients with thyroid cancer. The National Cancer Database (1998-2012) was queried for all adult patients with differentiated thyroid cancer and medullary thyroid cancer. Patients were divided into three groups: no ETE (T1 and T2 tumors), minimal ETE (T3 tumors <4 cm), and extensive ETE (T4 tumors <4 cm). Patient demographic, clinical, and pathologic factors were evaluated for all patients. A Cox proportional hazards model was developed for each histology to identify factors associated with survival. In total, 241,118 patients with differentiated thyroid cancer met the inclusion criteria; 86.9% had no ETE, 9.1% minimal ETE, and 4.0% extensive ETE. Compared with patients with no ETE, patients with minimal and extensive ETE were more likely to have larger tumors (1.4 cm vs. 1.8 cm and 2.0 cm, respectively), lymphovascular invasion (8.6% vs. 28.0% and 35.1%, respectively), positive margins after thyroidectomy (6.1% vs. 35.2% and 45.9%, respectively), and regional lymph node metastases (32.5% vs. 67.0% and 74.6%, respectively; all p < 0.01). After adjustment, minimal ETE (hazard ratio [HR] = 1.13; p < 0.01) and extensive ETE (HR = 1.74; p < 0.01) were associated with compromised survival for patients with differentiated thyroid cancer. In total, 3415 patients with medullary thyroid cancer met the inclusion criteria; 87.9% had no ETE, 7.1% minimal ETE, and 5.0% extensive ETE. Compared with patients with no ETE, patients with minimal and extensive ETE were more likely to have larger tumors (1.7 cm vs. 2.2 cm and 2.2 cm, respectively), lymphovascular invasion (19.2% vs. 68.9% and 79.3%, respectively), positive margins after thyroidectomy (5.8% vs. 44.1% and 51.9%, respectively), and regional lymph node metastases (39.0% vs. 90.5% and 94.4%, respectively; all p < 0.01). After adjustment, extensive ETE (HR = 1.63; p = 0.01) was associated with compromised survival for patients with medullary thyroid cancer. In patients with differentiated and medullary thyroid cancers, ETE is associated with compromised survival. Given these findings, ETE should be included in the thyroid cancer treatment guidelines.

Soft tissue invasion of papillary thyroid carcinoma.

Extrathyroidal extension (ETE) of papillary thyroid carcinoma (PTC) is common and clinical presentation can vary from minimal to extensive locoregional involvement. Although PTC is generally considered the most benign among all thyroid carcinomas, it may present with local invasion with poor prognosis. Our retrospective study involved 3267 PTC patients undergoing regular follow-up at Chang Gung Medical Center in Linkou, Taiwan. Among them, 269 were PTC cases with ETE, having tumors greater than 1 cm in size and treated with total or complete thyroidectomy with or without lymph node dissection for which the follow-up period was over 10 years. The mean age of 269 cases was 46.8 ± 15.1 (range 11–83 years) years. The number of females was 204 (75.8 %). Patients were categorized into minimal ETE (175 cases) and extensive ETE (94 cases) groups according to surgical findings and pathological reports. Mean follow-up period was 13.3 ± 5.5 (range 0.2–29.3) years, during which 28 (10.4 %) patients died of thyroid cancer; and 63 (23.4 %) of all-cause mortality. Multivariate analysis showed that age, gender, extensive ETE, and lymph node metastasis had a statistically significant effect on thyroid cancer mortality. Survival rates were significantly different between minimal ETE and extensive ETE groups (p < 0.0001). In conclusion, perithyroidal soft tissue involvement by PTC is an important factor that determines patient prognosis and a closer follow-up and more aggressive treatment is necessary for patients who are old, male, extensive ETE, and with lymph node involvement.

Inter-Observer Variation in the Pathologic Identification of Minimal Extrathyroidal Extension in Papillary Thyroid Carcinoma.

Extrathyroidal extension (ETE) is a significant prognostic factor in papillary thyroid carcinoma (PTC). Minimal extrathyroidal extension (mETE) is characterized by involvement of the sternothyroid muscle or perithyroid soft tissue, and is generally identified by light microscope examination. Patients with mETE, identified pathologically, are automatically upstaged to pT3. However, the prognostic implications of mETE have been a source of controversy in the literature. Moreover, there is also controversy surrounding the identification of mETE on pathological specimens. The objective of this study was to determine the level of agreement among expert pathologists in the identification of mETE in PTC cases. Eleven expert pathologists from the United States, Italy, and Canada were asked to perform a review of 69 scanned slides of representative permanent sections of PTC specimens. Each slide was evaluated for the presence of mETE. The pathologists were also asked to list the criteria they use to identify mETE. The overall strength of agreement for identifying mETE was slight (κ = 0.14). Inter-pathologist agreement was best for perithyroidal skeletal muscle involvement (κ = 0.46, moderate agreement) and worst for invasion around thick-walled vascular structures (κ = 0.02, slight agreement). In addition, there was disagreement over the constellation of histologic features that are diagnostic for mETE, which affected overall agreement for diagnosing mETE. Overall agreement for the identification of mETE is poor. Disagreement is a result of both variation in individual pathologists' interpretations of specimens and disagreement on the histologic criteria for mETE. Thus, the utility of mETE in staging and treatment of PTC is brought into question. The lack of concordance may explain the apparent lack of agreement regarding the prognostic significance of this pathologic feature.

Papillary thyroid carcinoma: different clinical behavior among pT3 tumors.

pT3 papillary thyroid carcinoma (PTC) can be divided into three subgroups according to the largest diameter >4cm or evidence of minimal extrathyroidal extension (ETE): A >4cm, no ETE; B ≤4cm, with ETE; and C >4cm, with ETE. The aim of this study was to analyze whether these subgroups are clinically different. A retrospective analysis of clinicopathological data of patients with pT3 PTC, with a minimum follow-up of 2years, at a referral center was conducted. Outcome was evaluated after primary treatment and after 2 and 5years of follow-up. Patients were classified as no evidence of disease (NED), biochemical evidence of disease (BED), and structural evidence of disease (SED) either locoregional (SED-L) or at distance (SED-D). The study patients were classified into three groups as follows: Group A (n=91), Group B (n=101), and Group C (n=23). Most patients were female (80.0%); mean age at diagnosis was 49.9±16.5years. 214 patients underwent total thyroidectomy; 208 patients were treated with (131)I. Median follow-up was 6.0years. After primary treatment, the condition of NED was significantly different between the groups (A-87.9%, B-68.3%, C-43.5%; p<0.001). Recurrence rate, either biochemical or structural, was 8.8, 7.2, and 30.0% in groups A, B, and C, respectively. Clinical status after 2years anticipated clinical status after 5years, except for Group B. ETE and tumor size were found to be predictors of disease status after primary treatment and after 2years. ETE appeared as the strongest predictor of persistence of disease after primary treatment as well as of evidence of disease, either biochemical or structural, after 2years of follow-up.

Predictors of Regional Lymph Node Recurrence after Initial Thyroidectomy in Patients with Thyroid Cancer.

Background. Regional lymph node recurrence (RLNR) is common in patients with thyroid cancer but clinicopathological predictors are unclear. We aimed to clarify these predictors and identify patients who would benefit from prophylactic lymph node dissection the most. Method. 343 patients with different types of thyroid cancer were analyzed retrospectively. All patients underwent total thyroidectomy between 2007 and 2013. Results. The median ± interquartile range of patients' age was 40 ± 25 years. 245 (71.4%) patients were female. Regarding the risk of regional lymph node recurrence, we found that male gender, age ≥45 years, non-PTC (i.e., medullary, follicular, and anaplastic types) histopathology, T3 (i.e., tumor size >4 cm in the greatest dimension limited to the thyroid or any tumor with minimal extrathyroid extension), stage IVa, and isolated cervical lymphadenopathy as initial manifestation (ICL) are significant risk factors. T3 (p < 0.001; odds ratio = 156.41, 95% CI [55.72–439.1]) and ICL (p < 0.001; odds ratio = 77.79, 95% CI [31.55–191.81]) were the strongest predictors of regional lymph node recurrence. Conclusion. We found easily achievable risk factors for RLNR in thyroid cancers patients. We suggested that patients with specific clinicopathological features like male gender, age ≥45 years, larger tumor size, and extrathyroidal extension be considered as prophylactic lymphadenectomy candidates.

Minimal extrathyroid extension in papillary thyroid carcinoma does not result in increased rates of either cause-specific mortality or postoperative tumor recurrence

This study assessed the influence of extrathyroid extension (EE) on cause-specific mortality (CSM) and tumor recurrence (TR) in patients treated for papillary thyroid carcinoma (PTC). We studied outcome in 3,524 patients with PTC without distant metastases at diagnosis. CSM and TR were investigated in 422 patients with gross EE (GEE) or microscopic EE (MEE). The 30-year CSM rate for GEE of 25% was 12-fold greater (P < .001) than 2% seen with surgically intra-thyroid tumors (SIT); no patient who underwent MEE died of PTC. No difference (P = .36) existed in CSM rates between 127 MEE and 3,102 microscopically intra-thyroid tumors (MITs). The 20-year TR rate for GEE was 43% versus 12% with SIT (P < .001). Analyzing only 2,067 pN0 tumors, we found that GEE patients had greater TR rates (all sites), compared with SIT or MEE (P < .001). When 44 MEE were compared with 1,941 MIT cases, TR (all sites) rates were not different (P = .74). In patients aged >45 with tumors <41 mm, 20-year TR rates for MIT (stages I/II) and MEE (stage III) were not different at 4.7% and 3.8% (P = .71). MEE without concomitant GEE did not increase rates of either CSM or TR in PTC. Accordingly, these results raise concerns regarding current AJCC staging recommendations.

Correlation of minimal extrathyroidal extension with pathologic features of lymph node metastasis in patients with papillary thyroid carcinoma.

The impact of minimal extrathyroidal extension (mETE) to the prognosis of patients with papillary thyroid carcinoma (PTC) is controversial. In this study, we investigated whether mETE is related to the aggressive biology of metastatic lymph node (LN) in patients with PTC. A retrospective review of 369 patients who had biopsy-confirmed cervical LN metastasis after initial surgery for PTC was conducted. The correlations of mETE with the specific features of metastatic LNs such as the LN size, number, LN ratio, and presence of extranodal extension (ENE) were statistically analyzed. Size of the primary tumor (≥1 cm) had independent correlations to mETE (HR = 5.750). While mETE was related to number of metastatic LNs (≥5), LN ratio (≥0.31) and ENE in univariate analysis, only ENE (HR = 2.322) was independently correlated to mETE in our series. Along with mETE, size of primary tumor (≥1 cm) had significant impact on ENE (HR = 2.107). Minimal ETE particularly those with larger primary tumor (≥1 cm) may be still considered as a significant factor regarding the management of cervical LNs in patients with PTC.

Characteristics and significance of minimal and maximal extrathyroidal extension in papillary thyroid carcinoma

Maximal extrathyroidal extension (ETE) is known to be an important prognostic factor in papillary thyroid carcinoma (PTC). However, the significance of minimal ETE is controversial. The aim of this study was to investigate the clinicopathologic characteristics and prognostic significance of minimal vs maximal ETE in PTC. A group of 967 patients who underwent thyroidectomy for PTC in a tertiary hospital between January 2000 and December 2011 were studied retrospectively. Patients were classified into three groups: absence of ETE, and minimal and maximal ETE. The minimal ETE group was further categorized into two subgroups according to invasion of strap muscles or no invasion (STI+ and STI-). Gender did not differ between the three groups of patients. The mean age of the patients with maximal ETE was significantly higher than in those belonging to the other groups. Tumor size, bilaterality, lymph node metastasis and stage increased significantly according to the degree of ETE. Recurrence and survival rates did not differ between the absence and minimal ETE groups, or between the STI- and STI+ subgroups of minimal ETE. However, the maximal ETE group had significantly higher recurrence and lower survival rates than the other groups (P<0.001). Maximal ETE is a significant factor for poor prognosis. However, minimal ETE is not associated with increased recurrence or decreased survival in patients with PTC.

Clinicopathological Significance of Minimal Extrathyroid Extension in Solitary Papillary Thyroid Carcinomas.

BackgroundThe definitive diagnosis of minimal extrathyroid extension (ETE) is subjective because a well-defined true capsule is absent in the thyroid gland. We subclassified the extent of minimal ETE and investigated the clinicopathological significance of the presence of minimal ETE in patients with solitary papillary thyroid carcinomas (PTCs) and solitary papillary thyroid microcarcinomas (PTMCs).MethodsA series of 546 patients with solitary PTCs, including 144 patients with solitary PTMCs, were retrospectively analyzed. Whether the presence of minimal ETE had an effect on recurrence-free survival (RFS) along with other clinicopathological parameters was investigated.ResultsThe only independent prognostic factor found to be associated with recurrence was the presence of LN metastasis in solitary PTC (p = 0.002) but not in solitary PTMC groups (p = 0.073). The presence of minimal ETE had no effect on RFS in both solitary PTC (p = 0.053) and solitary PTMC (p = 0.816). ConclusionsThe presence of minimal ETE has no significant influence on RFS in solitary PTC and PTMC. There is a risk of overrepresenting the T3 category in solitary PTC and PTMC patients with minimal ETE.Electronic supplementary materialThe online version of this article (doi:10.1245/s10434-015-4659-0) contains supplementary material, which is available to authorized users.

Oncologic Outcomes of Robotic Thyroidectomy: 5 Years’ Experience

Objectives: The feasibility and early surgical outcomes of robotic thyroidectomy have been reported. However, its oncologic outcomes are not well established. The aim of this study is to evaluate oncologic outcomes of robotic thyroidectomy compared with conventional thyroidectomy in differentiated thyroid carcinoma (DTC). Methods: We analyzed 925 DTC patients who underwent robotic thyroidectomy (204 cases) using a gasless unilateral axillo-breast or axillary approach, or conventional open thyroidectomy (721 cases) with or without central neck dissection (CND) from October 2008 to December 2013. We excluded patients who underwent simultaneous lateral neck dissection or completion thyroidectomy and cases with recurrent cancer, other types of malignancy, or distant metastasis. Results: The male ratio and the mean age were significantly lower in the robotic group ( P &lt; .001). The mean tumor size, minimal extrathyroidal extension, and stage did not differ between the 2 groups. The rate of total thyroidectomy was higher in the open group ( P &lt; .001). The rate of CND and the mean number of lymph nodes removed in the central compartment was not different between the 2 groups. Operative time was significantly longer in the robotic group ( P &lt; .001). Postoperative complications did not differ between the 2 groups, except transient hypoparathyroidism. Recurrence rate did not differ between the 2 groups after a mean follow-up of 33 months (0 % vs 0.4% in the robotic vs open groups, P = 1.0). Conclusions: The oncologic outcome of robotic thyroidectomy in 5 years’ experience is comparable with conventional thyroidectomy in selected patients with DTC.

Extrathyroidal Extension Predicts Extranodal Extension in Patients with Positive Lymph Nodes: An Important Association That May Affect Clinical Management

While there is consensus that significant extrathyroidal extension (ETE) (T4) should upstage a patient with well-differentiated thyroid cancer, the importance of minimal ETE (T3) remains controversial. Additionally, the importance of nodal metastases on prognosis has come under scrutiny. Recent publications highlight the importance of size, number of positive nodes, and, in particular, the presence of extranodal extension (ENE) as measures of disease aggressiveness. In this study, we examined whether ETE is a predictor of ENE. A retrospective review was conducted from January 2004 to March 2013. All node-positive patients who underwent total or completion thyroidectomy were included. Histologic features defined by the College of American Pathologists (CAP) protocol for thyroid carcinoma were recorded. A total of 193 patients qualified for review. Patients who were found to have ETE were 12 times more likely to have lymph nodes in the primary setting with ENE than patients with intrathyroidal primary tumors (p<0.000). After exclusion of all T4 cases (n=6), patients with minimal ETE were 13 times more likely to have ENE than those with no ETE (p<0.000). Twenty percent of microcarcinomas with ETE demonstrated ENE. We have found that the biology of the primary tumor is conferred to the lymph node in that the presence of ETE leads to a significantly higher incidence of ENE. Awareness of this relationship should be accounted for in the management of primary and recurrent lymph nodes. This study shows that minimal ETE is a significant predictor of ENE. Although long-term survival and recurrence follow-up is not available for the majority of patients in this series, the presence of ENE as a surrogate for more aggressive disease biology and its strong association with minimal ETE supports the upstaging of patients with minimal ETE.

Preoperative prediction of the extrathyroidal extension of papillary thyroid carcinoma with ultrasonography versus MRI: A retrospective cohort study

BackgroundThe purpose of this study was to assess the diagnostic performance of preoperative ultrasonography (US) for the prediction of extrathyroidal extension (ETE) in patients with papillary thyroid carcinoma (PTC) and to compare the diagnostic performances of US and magnetic resonance imaging (MRI) for predicting ETE. Methods75 patients with PTC who underwent preoperative US and MRI were retrospectively reviewed in this study. Two radiologists independently evaluated the US and MR findings to assess minimal or extensive ETE of PTC. These results were compared with the histopathologic findings. The diagnostic performances of US and MRI in the evaluation of ETE were compared. ResultsUS was more accurate than MRI in the prediction of minimal ETE (p < 0.05) and the accuracies were not significantly different between US and MRI in extensive ETE. US showed higher sensitivity, negative predictive value and accuracy than MRI (p < 0.001) in the prediction of overall ETE. ConclusionUS provided higher accuracy for assessing overall ETE and higher sensitivity for minimal ETE than MR imaging in preoperative evaluation of ETE of PTC. There was no significant difference in evaluating extensive ETE of PTC between US and MRI.

Radioactive iodine treatment for node negative papillary thyroid cancer with capsular invasion only: Results of a large retrospective study

With thyroid carcinoma the decision to use radioactive iodine (RAI) ablation depends on the risk of poor outcomes. Although extrathyroid extension (ETE) is well known as a risk of poor outcomes for papillary thyroid carcinoma (PTC), the definition of minimal ETE is too broad, as it encompasses both microscopic invasion of the thyroid capsule (capsular invasion [CI]) and macroscopic invasion of the sternothyroid muscle. We conducted a retrospective study to analyze the prognostic benefit of RAI ablation according to the presence of CI in a consecutive series of patients with PTC between October 1997 and December 2008. We studied two groups of patients, including those who received RAI (group I, n = 121) and those who did not (group II, n = 108). During follow-up, we assessed the locoregional recurrence of all patients. There were no statistically significant difference between the groups regarding locoregional recurrence at follow-up (13.2% for group I vs 9.3% for group II, P = 0.441). The association between RAI and locoregional recurrence in PTC patients with CI remained insignificant after adjusting for potential confounders, such as age, tumor size, sex, lymphatic invasion, vascular invasion and tumor multiplicity (P = 0.409, hazard ratio = 0.698, 95% confidence interval, 0.298-1.639). This retrospective study suggests that RAI treatment is not associated with less locoregional recurrence in PTC patients who only demonstrate CI, although further prospective studies are required to confirm these findings.