Nodule Size Effect on Diagnostic Performance of Ultrasonography and Computed Tomography for Papillary Thyroid Carcinoma.

Objective To compare the clinical features and 131I efficacy of papillary thyroid microcarcinoma (PTMC) and papillary thyroid carcinoma (PTC) except for PTMC. Methods PTC patients who were undergoing 131I treatment after total thyroidectomy were divided into the PTMC group (≤1.0 cm) and the papillary non-microcarcinoma group (>1.0 cm) according to tumor diameter. The clinical data of both groups were retrospectively analyzed, and the prognoses of the patients were evaluated. The statistical software SPSS Statistics 22.0 was used to analyze the results via t test and chi-squared (χ2) test. Results The proportion of patients with lymph node and central lymph node metastases in the PTMC group was lower than that in the PTC group. The number of metastatic lymph nodes was less, and the difference was statistically significant (χ2=44.23, 23.56, 42.80, all P 0.05). A total of 197 patients in the two groups achieved clinical remission after treatment. The remission rate in the PTMC group was higher than that in the PTC group. Among the 197 clinical remission cases, 102 patients achieved clinical remission after the first treatment. Although more patients achieved clinical remission in the PTMC group than in the PTC group after the first treatment, no significant difference was noted between the two groups (χ2=3.18, P>0.05). Conclusions The clinical features of PTMC patients differ from those of PTC patients. The overall cure rate of PTMC after 131I treatment is higher than that of PTC. The development of individualized treatment plans for PTMC patients is recommended to achieve good therapeutic effect and prognosis. Key words: Thyroid neoplasms; Iodine radioisotopes; Papillary thyroid microcarcinoma; Papillary thyroid carcinoma; Clinical feature; Prognosis

Aim: The aim of this study is to reveal the value of preoperative neutrophil lymphocyte ratio in differential diagnosis between papillary thyroid carcinoma, papillary thyroid microcarcinoma and benign multinodular goiter. Materials and methods: Patients with papillary thyroid carcinoma, papillary thyroid microcarcinoma, and multinodular goiter whose histopathological diagnosis was confirmed by postoperative pathology reports were included in the study. Results: The TSH levels were statistically significantly different among the groups (p < 0.001). The intergroup comparison revealed that the TSH levels were significantly lower in the multinodular goiter group compared to the papillary thyroid carcinoma and papillary thyroid microcarcinoma groups (p < 0.001, p0.001). The mean neutrophil count was 4.98 ± 1.19 in the papillary thyroid carcinoma group, 4.68 ± 1.33 in the papillary thyroid microcarcinoma group, and 4.59 ± 1.40 in the multinodular goiter group. The neutrophil counts of the groups were found to be significantly different (p = 0.013). The papillary thyroid carcinoma group had a significantly higher neutrophil count than the multinodular goiter group. The mean Neutrophil lymphocyte ratio value was 2.20 ± 0.71 in the papillary thyroid carcinoma group and 2.02 ± 0.92 in the multinodular goiter group. Neutrophil lymphocyte ratio values were significantly higher in the the papillary thyroid carcinoma group (p = 0.006). Conclucion: We believe that increased neutrophil lymphocyte ratio may be an indicator of underlying malignant disease in patients with thyroid nodules in the preoperative period.

ABSTRACTObjective:We aimed to evaluate the patients diagnosed with papillary thyroid carcinoma (PTC) and papillary thyroid microcarcinoma (PTMC) in terms of clinical, ultrasonographical (US) and histopathological features and their relationships with tumor size.Subjects and methods:We retrospectively evaluated 881 patients who underwent thyroid surgery in our clinic and diagnosed with PTC histopathologically were enrolled the study. Demographic characteristics, US findings and histopathological features were evaluated.Results:In total, 1264 nodules were identified in the 881 patients. The incidentality rates were higher in the PTMC group and also in the ≤ 5 mm group. In total multifocality rate was 32.9%, and was significantly higher in PTMC group than the PTC group. PTC and > 5 mm PTMC groups compared to PTMC and ≤ 5 mm groups respectively, were more aggresive histopathological features.Conclusions:Since the incidentality rates were found significantly more common in our patients with PTMC and those with ≤ 5 mm, ultrasonographic features of the nodules should be evaluated carefully and for cases which are suspicious with US, US-guided fine needle aspiration biopsy (FNAB) should be considered in order to make the correct treatment strategy. Also our study revealed that PTC and > 5 mm PTMC groups compared to PTMC and ≤ 5 mm groups respectively, have more aggresive histopathological features.

To explore the invasiveness of papillary thyroid microcarcinoma(PTMC)with BRAF mutation. Totally 99 patients with PTMC with BRAF mutation were enrolled in this study, meanwhile another 97 patients with papillary thyroid carcinoma (PTC) (tumor size>1 cm)with BRAF mutation were included as controls. The clinicopathologic factors including extrathyroidal invasion, multifocality, and distant metastasis were analyzed. The rates of extrathyroidal invasion and nodal metastasis in PTMC group were as high as 16.10% and 71.74%, respectively. In the PTMC group and PTC group,the extrathyroidal invasion rate was 16.10% and 39.18%, cervical lymph node metastasis rate was 71.74% and 91.75%, and distant metastasis rate was 1.01% and 9.28%, respectively. In the PTMC subgroups with tumor sizes ≤0.3 cm, 0.3-0.6 cm, and 0.6-1.0 cm, the cervical lymph node invasion rate was 60.00%, 72.50%, and 73.81%, the extrathyroidal invasion rate was 10.00%, 9.09%, and 24.44%, and the multifocality rate was 60.00%, 38.64%, and 57.78%, respectively. Univariate analysis showed that the tumor size was not significantly correlated with multifocality (Χ (2)=3.752, P=0.153), cervical lymph node metastasis (Χ (2) = 0.780,P = 0.677), extrathyroidal invasion (Χ (2) = 4.182, P = 0.124), and distant metastasis (Χ (2)=1.212, P = 0.545). While the BRAF group and PTC group were not significantly different in multifocality (Χ (2) = 1.742, P=0.187), they were significantly different in terms of extrathyroidal invasion (Χ (2) = 13.000, P = 0.000), nodal involvement (Χ (2) = 12.819, P = 0.000), and distant metastasis (Χ (2) = 5.316, P = 0.021). Multivariate analysis showed that nodal metastasis was independently associated with size>1 cm (P=0.001) and extrathyroidal invasion (P=0.003). BRAF mutant PTMC manifests relative high extrathyroidal involvement and nodal metastasis, and the similar multifocality as BRAF mutant PTC. Radioactive iodine should be considered in PTMC with the presence of BRAF mutation combined with extrathyroidal invasion or nodal metastasis.

Papillary thyroid carcinoma (PTC) and papillary thyroid microcarcinoma (PTMC) are generally characterized as less invasive forms of thyroid cancer with favorable prognosis. However, once lateral cervical lymph node metastasis takes place, the prognosis may be significantly impacted. The purpose of this study was to evaluate whether there is a difference in the pattern of lateral lymph node metastasis between PTC and PTMC. A retrospective analysis was performed for PTC and PTMC patients that underwent central area dissection and unilateral lateral neck lymph node dissection (II-V area) between January 2020 and December 2021. Compared with PTMC group, the PTC group exhibited higher incidence of capsule invasion, extrathyroid invasion and lymphatic vessel invasion. Both the number and rate of central lymph nodes metastasis were elevated in the PTC group. While the number of lateral cervical lymph node metastasis was higher, the metastasis rate did not demonstrate significant difference. No significant differences were identified in the lymph node metastasis patterns between the 2 groups. The determination of the extent of lateral neck lymph node dissection solely based on the tumor size may be unreliable, as PTC and PTMC showed no difference in the number and pattern of lateral neck metastasis. Additional clinical data are warranted to reinforce this conclusion. For patients categorized as unilateral, bilateral, or contralateral cervical lymph node metastasis (including level I, II, III, IV, or V) or retropharyngeal lymph node metastasis who require unilateral lateral neck dissection, the size of the primary tumor may not need to be a central consideration when assessing and deciding the extent of lateral neck dissection.

PurposeEarly and accurate preoperative diagnosis of central lymph node metastasis (CLNM) is crucial to improve surgical management of patients with clinical lymph node-negative papillary thyroid carcinoma (PTC). Towards improving diagnosis of CLNM, we assessed the value of combining preoperative clinical characteristics, conventional ultrasound, and contrast-enhanced ultrasound (CEUS) in preoperative prediction of CLNM of different sized PTCs.Patients and MethodsPatients were divided according to tumor size: a PTC group (>10 mm) and a papillary thyroid microcarcinoma (PTMC) group (≤10 mm). We retrospectively analyzed the clinical and ultrasonographic features of 120 PTC patients and 165 PTMC patients. Multivariate logistic regression analysis was used to screen independent risk factors and establish prediction models. Receiver operating characteristic curves were used to determine the best cut-off values for continuous variables and assess the performance of prediction models.ResultsIndependent risk predictors of CLNM for the PTC group were extrathyroidal extension in CEUS (OR=7.923), tumor size >14 mm (OR=5.491), and multifocality (OR=3.235). For the PTMC group, the independent risk factors were the distance from the thyroid capsule =0 mm (OR=4.629), male (OR=3.315), tumor size >5 mm (OR=3.304), and microcalcification (OR=2.560). The predictive model of combined method had better performance in predicting CLNM of PTC compared with models based on CEUS and conventional ultrasound alone (area under the curve: 0.832 vs 0.739, P=0.0011; 0.832 vs 0.678, P=0.0012). For PTMC, comparing with CEUS, the combined method and conventional ultrasound performed better than CEUS alone in predicting CLNM (area under the curve: 0.783 vs 0.636, P=0.0016; 0.738 vs 0.636, P=0.0196).ConclusionThe predictive models of combined method obtained from significant preoperative clinical and ultrasonographic features can potentially improve the preoperative diagnosis and individual treatment of CLNM in patients with PTC and PTMC. CEUS may be helpful in predicting CLNM of PTC, but CEUS would be ineffective in predicting CLNM of PTMC.

The clinical significance of papillary thyroid microcarcinoma (PTMC) tumors < or =1 cm is widely debated. The objective of this study was to compare conventional papillary thyroid carcinoma (PTC) (tumors >1 cm) to PTMC and assess for differences in tumor characteristics and patient outcome. A retrospective chart review of patients with PTC or PTMC who were followed for a minimum of 3 years postoperatively and managed at a single academic institute was performed. Of 202 patients in the study, 66 (32.7%) had PTMC and 136 (67.3%) had conventional PTC. Patient and tumor characteristics including tumor multifocality, extrathyroidal extension, angiolymphatic invasion, and lymph node metastasis were similar between both groups. Twenty-one percent of the PTMC tumors were discovered incidentally. Patients with conventional PTC were significantly more likely to undergo treatment with radioactive iodine therapy compared to PTMC patients (86.4% vs. 66.7%, respectively, p < 0.003). Disease recurrence was observed in 40 patients and was not statistically different between the two groups; 11 (16.7%) in PTMC and 29 (21.3%) in conventional PTC, p = 0.57. Within the PTMC group, tumors of patients that recurred were significantly larger than those who remained disease free (8.1 mm vs. 6.4 mm, p < 0.05). None of the patients with incidental PTMC had disease recurrence. Angiolymphatic invasion was the only significant prognostic indicator of recurrence on multivariate analysis (p < 0.02). Nonincidental PTMC can have aggressive tumor features and disease recurrence similar to conventional PTC. These tumors should be managed like any other papillary thyroid malignancy.

Objective To investigate the clinical characteristics of papillary thyroid carcinoma (PTC) complicated by multinodular goiter (MG). Methods The clinical data of 130 PTC patients treated in the First People’s Hospital of Zhaoqing from July 2013 to July 2017 were retrospectively reviewed. Among them, 88 patients with nodular goiter were selected and were treated as PTC combined with MG group, and 42 patients without nodular goiter were selected and were treated as PTC group. The differences in clinical characteristics, such as age, gender, location of lesions, nodule diameter, lymph node metastasis, ultrasonographic features and postoperative complications were compared between the two groups. Results The incidence of papillary thyroid microcarcinoma(PTMC), age of PTC, location of lesions and rate of cervical lymph node metastasis were significantly different between PTC combined with MG group and PTC group (P 0.05). In the field of ultrasound imaging, the characteristics of cancer, including echo, nature, density, boundary, internal blood flow, calcification and lymph node enlargement, were not significantly different between the two groups (P>0.05). There was no severe complication occurred in the two groups. Conclusions PTC complicated by MG goiter often occurs in women over 40 years old. The main form is PTMC, cancer is often located in the unilateral leaf gland, and incidence of lymph node metastasis in early stage is low, and there are some general rules that can be followed in ultrasound characteristics. Key words: Papillary thyroid carcinoma; Multinodular goiter; Clinical characteristics

To explore the relationship between serum level of thyroxin-stimulating hormone (TSH) and development and progression of papillary thyroid microcarcinoma (PTMC) in nodular thyroid disease. A total of 365 eligible patients with thyroid nodules undergoing initial thyroidectomy were enrolled, including 113 patients with PTMC diagnosed by postoperative pathology (PTMC group) and 252 patients with benign thyroid nodules (BTN group). Their clinical data were retrospectively reviewed. The serum levels of TSH in two groups and the proportion of PTMC in different serum TSH level groups in all patients were compared respectively. The relationship of preoperative serum TSH levels with tumor size and lymphatic metastasis in patients with PTMC were analyzed. No significant difference existed in serum TSH levels between PTMC and BTN groups (P > 0.05). The median age was younger in PTMC group than that in BTN group (Z = -2.877, P = 0.004). And the TGAb levels were higher in PTMC group than those in BTN group (Z = -2.887, P = 0.004). They were divided into 6 groups according to the serum TSH levels, and there weren't significant difference in the proportion of PTMC among those group (P > 0.05). Binary logistic regression analysis showed age was the only risk factor of PTMC (OR = 0.971, 95%CI: 0.953-0.990, P = 0.003). The serum TSH levels were positively correlated with tumor size in patients with PTMC (r = 0.218, P = 0.025). However, the proportions of lymphatic metastasis were comparable among different TSH levels groups in patients with PTMC (P > 0.05). Serum TSH is probably associated with the de novo oncogenesis of PTMC. However, serum TSH may be involved in the growth of preexisting PTMC.

Virtual noncontrast (VNC) images generated by dual-layer spectral computed tomography (DLCT) remove iodine influence from enhanced images to simulate true noncontrast (TNC) images. Previous research has demonstrated the high comparability of abdominal VNC images with TNC images, suggesting their potential as substitutes. Given the thyroid's significant iodine content, this study evaluated the efficacy of VNC images for removing both intrinsic and extrinsic iodine through an analysis of computed tomography (CT) attenuation and iodine density in TNC and enhanced VNC thyroid images. A total of 115 thyroid nodules were classified into papillary thyroid carcinoma (PTC) and nodular goiter (NG) groups based on pathology. Patients underwent both noncontrast and enhanced neck scans, with attenuation values of CT and iodine density measured for nodules, normal thyroid, and the carotid artery on conventional and VNC images. The study calculated CT attenuation and iodine density for both intrinsic and external iodine content. The Wilcoxon rank-sum test was used to compare intrinsic and external iodine differences between the PTC and NG groups. The Spearman test was used for correlation assessment within each group, and Bland-Altman analysis was conducted to evaluate CT attenuation consistency between VNC images from nonenhanced scans (VNCn) and VNC images from enhanced scans (VNCe) within the groups. The CT attenuation values of intrinsic iodine showed no differences between nodules, normal thyroid, and carotid artery in the PTC and NG groups (P>0.05). However, there was a difference in the CT attenuation values of external iodine for nodules between the two groups (P<0.05), while no difference was found for normal thyroid or the carotid artery between the groups (P>0.05). The correlation between CT attenuation values of the nodules, normal thyroid, and carotid artery for intrinsic iodine and iodine density was high in both the PTC group (r=0.919, r=0.951, r=0.592, respectively; P<0.001) and the NG group (r=0.925, r=0.973, r=0.721, respectively; P<0.001). Similarly, there was a strong correlation between the CT attenuation values of the nodules, normal thyroid, and carotid artery for extrinsic iodine and iodine density in the PTC group (r=0.960, r=0.965, r=0.904, respectively; P<0.001) and the NG group (r=0.979, r=0.967, r=0.963, respectively; P<0.001). There was no statistically significant difference in the CT attenuation values of the normal thyroid in VNCn and VNCe images (P>0.05), while the CT attenuation values of nodules and the carotid artery in VNCn and VNCe images in the two groups were significantly different (P<0.05). Bland-Altman scatter plots showed that, apart from the normal thyroid in the NG group, the consistency of CT attenuation values on VNCn and VNCe images was generally poor (more than 5% of data points outside the consistency limit). VNC images show certain ability to remove intrinsic and external iodine from the thyroid. In the diagnosis of thyroid nodules, enhanced VNC images of the thyroid cannot replace conventional nonenhanced images.

Introduction/Objective. Association of Graves? disease (GD) and thyroid cancer is reported in a wide range from 0% to 33.7%. Papillary thyroid carcinoma (PTC) is the most commonly diagnosed malignancy in GD, namely its variant ? papillary thyroid microcarcinoma (PTMC). The increasingly frequent PTMC disclose favorable biological behavior with low mortality and recurrence rates. The aim of this work is to report our experience on the frequency and morphological features of PTMC in surgically treated patients with GD. Methods. Over a period of three years, total or near-total thyroidectomy was performed in 129 patients with GD. Results. Incidental PTMC was diagnosed in 24 (18.7%) patients with GD. The mean tumor diameter was 3.03 ? 2.17 mm. The average age of patients in the GD with PTMC group was 48.50 ? 13.07 years, while in the GD without PTMC group it was 41 ? 13.12 years, and it proved to be statistically significant ( p = 0.045). Most of the PTMC were unifocal (83%), and the most common morphological features of PTMC were intraparenchymal localization (62.5%), follicular morphology (66.7%), and infiltrative growth pattern (62.5%). Extrathyroidal extension, lymphatic invasion and multifocality of PTMC were more commonly related with subcapsular localized PTMC. The presence of at least one nodule in the GD with PTMC group was 58.3%, while in the GD without PTMC group it was 26.7%, and it was statistically significant (p = 0.003). Conclusion. Our results showed a high incidence of PTMC (18.7%) in patients with GD. Clinically, the most important morphological characteristics of PTMC were related with its subcapsular localization.

Background: Hemocytometer parameters can be important biomarkers for some types of cancers and diseases. There is a need to evaluate their biomarker potential in thyroid diseases. Objectives: The current study aimed at contributing to potential biomarker researches to diagnose papillary thyroid carcinoma (PTC) and benign multinodular goiter (BMG), evaluate the role of these markers to determine the PTC characteristics and contribute to clarification of controversial issues. Methods: The study was designed as a retrospective observational study. The study included 389 patients who underwent total thyroidectomy at private Sani Konukoglu hospital (Sanko University, School of Medicine, Gaziantep, Turkey) due to BMG or PTC diagnosis from November 2011 to May 2017. The study subjects were divided into 3 groups. Groups 1, 2, and 3 were subjects with BMG, PTC, and the control, respectively. The comparisons were made among the groups in terms of hemocytometer parameters. In the group with the thyroid papillary carcinoma diagnosis, the relationship between the hemocytometer parameters and the bilateral tumor presence, single-sided multicentrite, and tumor diameter (size) were investigated. Results: Red cell distribution width (RDW) levels were 15.50 ± 2.39, 15.68 ± 2.16, and 12.5 ± 1.51 in the BMG, PTC, and control groups, respectively. Mean platelet volumes (MPV) were 7.97 ± 1.19, 8.05 ± 1.20, and 7.23 ± 1.39 in the BMG, PTC, and control groups, respectively. MPV and RDW values were significantly lower in group 3 compared with the groups 1 and 2 (P < 0.0001). Plateletcrit (PCT) values were 0.22 ± 0.05, 0.23 ± 0.06, and 0.19 ± 0.05 in the BMG, PTC, and control groups, respectively. PCT was significantly lower in the group 3 compared with the groups 1 and 2 (P = 0.0001). In PTC group, no significant relationship was observed between any of the examined hematological parameters in terms of multicentric and bilateral tumor presence. Conclusions: RDW, MPV, haemoglobin content, and PCT were significantly higher in the BMG and PTC groups. This increase was not specific for either of the 2 groups. No significant difference was found between any of the hemocytometer parameters and the multicentricity and bilaterality of PTC. But, a possible correlation was observed between activated partial thromboplastin time (aPTT), hemoglobin content, and tumor size.

The aim of this study was to identify clinical features and therapeutic outcomes of patients with papillary thyroid cancer (PTC) according to tumor diameter and evaluate the correlation of neck lymph node (LN) involvement of papillary thyroid microcarcinoma (PTMC) according to patients' age. We divided 467 patients into two groups according to tumor diameter: PTMC group (≤1 cm) and non-PTMC group (>1 cm). The clinical data were analyzed retrospectively. Thereafter, we divided the PTMC patients into three subgroups according to age: young subgroup (<45 years), middle subgroup (45-54 years), and old subgroup (≥55 years). A further study about clinical features, especially the neck LN involvement in three subgroups, was analyzed. All patients received radioiodine ablation at least once. There were more patients with a single cancer lesion and cancer in the unilateral lobe, less number of neck LN involvement, fewer patients with neck lymph node metastasis (LNM), and more patients with Hashimoto's thyroiditis in PTMC group than in non-PTMC group. At the further evaluation, 58.03% patients maintained clinical remission, which was more in the PTMC group than in non-PTMC group. There was no significant difference in recurrence, but the disease-free survival rate of patients in the PTMC group was higher than in the non-PTMC group. In the PTMC group, the radioactive iodine curative ratio in younger patients is lower than that in the other two subgroups. Both the LNM and central LNM (CLNM) rates were significantly higher in young patients compared with older patients. In addition, the LNM-positive group had more male patients, larger tumor size, and higher thyroglobulin antibody level. Both LNM and the CLNM rates were significantly higher in the young subgroup than in the older subgroup. Young and middle age and extrathyroid extension were independent risk factors for neck LNM. Unlike LNM, young age, extrathyroid extension, and male sex were independent risk factors for CLNM. Some PTMCs were less aggressive and the therapeutic outcomes of them were better than non-PTMC. Moreover, PTMCs in young patients were more aggressive, especially in LNM. Hence, clinicians should consider an individualized treatment according to tumor characteristics and age to achieve better therapeutic efficacy.

BackgroundOvertreatment of papillary thyroid microcarcinoma (PTMC) has become a common concern. This study aimed to compare clinicopathological features between PTMC and papillary thyroid carcinoma (PTC) and to explore whether surgery can confer significant survival benefits in all patients with PTC or PTMC.MethodsData of 145,951 patients with PTC registered in Surveillance, Epidemiology, and End Results (SEER) database and 8,751 patients with PTC in our institution were retrospectively collected. Patients with tumors less than 10 mm in diameter were classified as PTMC cohort and the rest as PTC cohort. Clinicopathological features between PTMC and PTC were compared on the basis of SEER cohort and validated with institutional data. Survival analysis was conducted to explore the effect of surgery on the prognosis of patients. To minimize potential confounders and selection bias, we performed propensity score matching (PSM) analysis to match more comparable cohorts.ResultsCompared with PTC, PTMC exhibited the following characteristics: more common in women and whites, older age at diagnosis, lower proportion of follicular variants, intraglandular dissemination, extraglandular and capsular invasion, higher proportion of multifocality, fewer lymph node and distant metastases, and higher cancer-specific survival (CSS) and overall survival (OS) (all p-value < 0.05). Regarding treatment, patients with PTMC received a lower proportion of radiotherapy, chemotherapy, and total thyroidectomy but a higher proportion of lobectomy and/or isthmectomy. There was no significant difference in CSS for patients with PTMC at stage T1N0M0 with or without surgery (P = 0.36).ConclusionGenerally, PTMC showed higher biological indolence than PTC, which meant a higher survival rate for patients in both OS and CSS. For patients with PTMC at staged T1N0M0, active surveillance (AS) may be a potentially feasible management strategy. However, the maintenance of good medical compliance and the management of psychological burden cannot be ignored for patients included in AS.

Herein, we report a case of an occult thyroid cancer that was not detected as a primary tumor on preoperative ultrasonography or postoperative pathological examination, although a diagnosis of papillary thyroid carcinoma metastasis was made owing to the presence of a mass in the right upper neck. Needle biopsy of the mass in the right upper neck revealed positive results for thyroglobulin and TTF-1 on immunostaining, and a papillary thyroid carcinoma was observed with papillary and follicular patterns. We suspected papillary thyroid carcinoma (T0N1bM0) or ectopic papillary thyroid carcinoma. Accordingly, we performed total thyroidectomy, central lymph node dissection, right lateral neck dissection, and resection of the superficial lobe of the right parotid. A postoperative pathological examination of 5-mm slices of the specimen revealed no primary tumor in the thyroid. However, a hyalinized image of the thyroid indicated that a micropapillary thyroid carcinoma might have spontaneously disappeared. As there was no normal thyroid tissue in the metastasis to the superior internal jugular lymph node, the tumor was unlikely to be an ectopic papillary thyroid carcinoma. Therefore, we made a diagnosis of a papillary thyroid carcinoma (pT0N1bM0). After surgery, we determined that the tumor belonged to a high-risk group of papillary thyroid carcinomas and a poor-prognosis group of symptomatic papillary thyroid microcarcinomas; accordingly, ablation was performed with 30 mCi iodine-131. There was no recurrence or metastasis 24 months after the first surgery.