Size Of Papillary Thyroid Carcinoma Research Articles

Quantitative parameters of contrast-enhanced ultrasound effectively promote the prediction of cervical lymph node metastasis in papillary thyroid carcinoma.

Papillary thyroid carcinoma (PTC), the most common endocrine tumor, often spreads to cervical lymph nodes metastasis (CLNM). Preoperative diagnosis of CLNM is important when selecting surgical strategies. Therefore, we aimed to explore the effectiveness of quantitative parameters of contrast-enhanced ultrasound (CEUS) in predicting CLNM in PTC. We retrospectively analyzed 193 patients with PTC undergoing conventional ultrasound (CUS) and CEUS. The CUS features and quantitative parameters of CEUS were evaluated according to PTC size ≤ 10 or > 10 mm, using pathology as the gold standard. For the PTC ≤ 10 mm, microcalcification and multifocality were significantly different between the CLNM (+) and CLNM (-) groups (both P < 0.05). For the PTC > 10 mm, statistical significance was noted between the two groups with respect to the margin, capsule contact, and multifocality (all P < 0.05). For PTC ≤ 10 mm, there was no significant difference between the CLNM (+) and CLNM (-) groups in all quantitative parameters of CEUS (all P > 0.05). However, for PTC > 10 mm, the peak intensity (PI), mean transit time, and slope were significantly associated with CLNM (all P < 0.05). Multivariate analysis showed that PI > 5.8 dB was an independent risk factor for predicting CLNM in patients with PTC > 10 mm (P < 0.05). The area under the curve of PI combined with CUS (0.831) was significantly higher than that of CUS (0.707) or PI (0.703) alone in the receiver operator characteristic curve analysis (P < 0.05). In conclusion, PI has significance in predicting CLNM for PTC > 10 mm; however, it is not helpful for PTC ≤ 10 mm.

Correlations between the average Young's modulus and histopathological characteristics of papillary thyroid carcinoma

Objective: To explore the histopathological factors affecting the stiffness of papillary thyroid carcinoma (PTC). Methods: Ninety-six patients with PTC confirmed by surgery and pathology in Shanxi Bethune Hospital from January 2019 to December 2020 were selected, including 101 nodules. Two-dimensional ultrasound and shear-wave elastography (SWE) were performed before surgery and the average Young's modulus (Emean) of PTC nodules were measured. Histopathological examinations on the nodules were conducted after surgery to decide the lesion size, number of lesions, calcification type, presence or absence of capsular and extracapsular invasion, degree of fibrosis, microvessel density, and number of tumor cells. The correlations between the lesion size, degree of fibrosis, microvessel density, and number of tumor cells and the Emean were analyzed. The Emeans of nodules with different numbers of lesions, presence or absence of capsular and extracapsular invasion, and different pathological calcification types were compared. The multiple linear regression analysis was used to evaluate the histopathological factors influencing the Emean. Results: The ranges of the lesion sizes, degrees of fibrosis, microvascular density, numbers of tumor cells, and the Emeans of the 101 investigated PTC nodules were (1.29±0.95) cm, (30.64±18.37)%, (101.64±30.7) vessels per high power field, (373.52±149.87) cells per high power field, and (36.47±19.62) kPa, respectively. Correlation analysis showed that the lesion size of PTC and the degree of fibrosis were positively correlated with the Emean (r=0.660, P＜0.001; r=0.789, P＜0.001), while the microvessel density was negatively correlated with the Emean (r=-0.198, P=0.047). The Emean of the group with capsular and extracapsular invasion was higher than that of the group without (P=0.014). There were statistical differences in the Emeans among different types of pathological calcification (P＜0.001). The multiple linear regression analysis showed that the lesion size (β=0.325, P＜0.001), degree of fibrosis (β=0.563, P＜0.001), psammoma bodies (β=0.177, P=0.001), stromal calcification (β=0.164, P=0.003), and mixed calcification of both psammoma bodies and stroma (β=0.163, P=0.003) were independent influencing factors for the Emean. The degree of fibrosis had the greatest impact on the Emean. Conclusions: The Emean of PTC lesions was correlated with the histopathological characteristics of PTC. The lesion size, degree of fibrosis, and calcification had significant impact on the Emean, among which the degree of fibrosis had the greatest impact.

Value of Contrast-Enhanced Ultrasound in the Preoperative Evaluation of Papillary Thyroid Carcinoma Invasiveness.

ObjectiveTo evaluate the diagnostic performance of preoperative contrast-enhanced ultrasound (CEUS) in the detection of extracapsular extension (ECE) and cervical lymph node metastasis (LNM) of papillary thyroid carcinoma (PTC) and the added value of CEUS in the evaluation of PTC invasiveness to conventional ultrasound (US).Materials and MethodsA total of 62 patients were enrolled retrospectively, including 30 patients with invasive PTCs (Group A, ECE or LNM present) and 32 patients with non-invasive PTCs (Group B). All patients underwent US and CEUS examinations before surgery. US and CEUS features of PTCs and lymph nodes were compared between groups. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of US, CEUS, and the combination of the two in the detection of ECE and LNM of PTCs were calculated. Logistic regression was used to analyze relationships between variables.ResultsThe PTC size was larger in group A on both US and CEUS (P = 0.001, P = 0.003). More PTCs showed hyper-enhancement in group A (P = 0.013) than in group B. More PTCs had >25% contact between PTC and the thyroid capsule and discontinued capsule on US and CEUS (all P < 0.05) in group A than in group B. More absent hilum and calcification of lymph nodes were observed in group A (both P < 0.05) than in group B on US. More centripetal perfusion and enlarged lymph nodes were observed in group A (both P < 0.05) than in group B on CEUS. CEUS alone and US combined with CEUS manifested higher diagnostic accuracy (79.0%) than US alone (72.6%) in the detection of ECE. The combination of US and CEUS manifested the highest diagnostic accuracy (95.2%) than CEUS alone (90.3%) and US alone (82.2%) in the detection of LNM. Diagnoses of ECE and LNM by the combination of US and CEUS were independent risk factors for PTC invasiveness [odds ratio (OR) = 29.49 and 97.20, respectively; both P = 0.001].ConclusionCEUS or US combined with CEUS is recommended for the detection of PTC ECE, while the combination of US and CEUS is most recommended for LNM detection. CEUS plays an essential role in the preoperative evaluation of PTC invasiveness.

Ultrasonographic Features, Nodule Size, Capsular Invasion, and Lymph Node Metastasis of Solitary Papillary Carcinoma of Thyroid Isthmus.

Objective: This retrospective study aimed to analyze the ultrasound (US) imaging features of solitary papillary thyroid carcinoma (PTC) located in the isthmus and to assess the risk factors for lymph node metastasis (LNM) and tumor capsular invasion.Methods: We included a total of 135 patients with solitary PTC located in the isthmus. All the cases underwent US, total thyroidectomy, and prophylactic central lymph node dissection. Patients' demographic and thyroid isthmus nodules' US characteristics, as well as risk factors associated with LNM and tumor capsular invasion, were analyzed.Results: It was revealed that the occurrence of LNM was higher in male patients than in female patients (P < 0.001). As risk factors, the size of PTC in the isthmus was found to be associated with LNM and tumor capsular invasion (P = 0.005 and 0.000, respectively). The area under the receiver operating characteristic curve (AUC) of the size of the isthmus PTC was 0.64 [95% confidence interval (CI) = 0.55–0.72], indicating a probability for LNM. The AUC value for tumor capsular invasion was 0.77 (95% CI: 0.68–0.83). When the threshold was set to 1.1 cm, the larger size indicated that there was a probability of occurrence of LNM with sensitivity and specificity of 47.4 and 73.7%, respectively. When the threshold was set to 0.7 cm, the larger size indicated that there was potentially a tumor capsular invasion, with sensitivity and specificity of 80.6 and 56.3%, respectively. Wider-than-tall nodules were found to be significantly different from those in LNM and tumor capsular invasion (P = 0.038 and 0.030, respectively). There were significant differences in tumor capsular invasion in extrathyroidal extension (ETE) compared with smooth or ill-defined and lobulated or irregular nodules (P = 0.017).Conclusions: This study showed that the incidence of LNM in male patients was higher than that in female ones. When a US image shows a thyroid isthmus nodule with a wider-than-tall shape, LNM and tumor capsular invasion were likely to occur. When a US image shows a thyroid isthmus nodule with an ETE, tumor capsular invasion was likely to occur. ETE and wider-than-tall may be indicators of FNA under US guidance, even though the size of thyroid isthmus nodule may be <1 cm.

ANGPTL4 Promotes the Proliferation of Papillary Thyroid Cancer via AKT Pathway.

PurposeAlthough papillary thyroid carcinoma (PTC) is associated with a generally favorable prognosis, about 15% of patients present recurrence and distant metastasis in the next decade leading to death. Angiopoietin-like 4 (ANGPTL4) is secreted to circulation and belongs to the angiopoietin-like proteins. The expression of ANGPTL4 was increased in several solid tumor tissues compared to corresponding paracancerous tissues. ANGPTL4 was identified as pro-tumorigenic protein, including stimulating tumor cell growth, promoting tumor metastasis. However, the clinical significance and biological function of ANGPTL4 in PTC is still unclear. Hence, the purpose of this study was to evaluate the role of ANGPTL4 in PTC, investigating the possibility of whether ANGPTL4 could become a novel target for PTC therapy.MethodsWe investigated the expression level of ANGPTL4 and pAKT in PTC and paracancerous tissue by immunohistochemistry. We determined the effect of ANGPTL4 in PTC cell proliferation through cell counting kit-8 (CCK-8) and cell cycle by flow cytometry analysis. Furthermore, the correlation between ANGPTL4 expression levels and PTC cell proliferation from the TCGA data set was analyzed by GSEA. We explored the role of ANGPTL4 on the phosphorylation of AKT and proliferation in PTC cells via overexpression or knockdown assays and AKT inhibitor assay.ResultsIn the present study, we found that ANGPTL4 was highly expressed in both protein and mRNA level in PTC compared with adjacent noncancerous tissues or benign nodule. ANGPTL4 expression increased according to thyroid tumor progression. ANGPTL4 level was positively correlated with the size of PTC. ANGPTL4 increased cell proliferation and decreased cell cycle arrest of PTC. Knockdown of ANGPTL4 inhibited the phosphorylation of AKT. ANGPTL4 regulated PTC cell proliferation through AKT signaling pathway.ConclusionOur findings suggested that ANGPTL4 was increased in PTC compared with adjacent noncancerous tissues, and ANGPTL4 increased cell proliferation and inhibited cell cycle arrest in PTC cells via promoting AKT phosphorylation. The study may provide fundamental information to suggest its suitability as a target for the treatment of PTC.

Cervical Lymph Node Metastases of Papillary Thyroid Carcinoma, in the Central and Lateral Compartments, in Children and Adolescents: Predictive Factors.

The aim of our study was to identify predictive factors for lymph node metastases (LNM) in children and adolescents with papillary thyroid carcinoma (PTC) and their impact on survival. The authors conducted an Italian multicentric retrospective analysis on 132 pediatric patients (0-18years old) affected by PTC between 2000 and 2014. The investigated variables were demographic characteristics of the patients, clinicopathological features of PTCs, and persistence/recurrence of disease. The female/male ratio was 3.1:1. The median age was 14.3±3.5years (range 4-18years). Total thyroidectomy was performed in all the patients, followed by lymph node dissection in 87 patients (65.9%). Metastatic lymph node involvement was confirmed in 73 patients (55.3%): lateral compartment (LC) in 25 patients (34.2%), central compartment (CC) in 17 patients (23.3%), and both compartments in 31 patients (42.5%). Multifocality (P<.00), vascular invasion (P=.04), infiltration of the thyroid capsule (P<.00), minimal extrathyroidal extension (P<.00), diffuse sclerosing variant of PTC (P=.02), and presence of LNM in the LC (P<.00) were significantly associated with LNM in CC. Infiltration of the thyroid capsule (P<.00), massive extrathyroidal extension (P=.03), distant metastases (P=.02), PTC, not otherwise specified (P<.00), and presence of LNM in the CC (P<.00) were significantly associated with LNM in LC. Age, sex and size of PTC were not correlated with the presence of cervical LNM. Moreover, presence of LNM in CC increases the risk of persistence (P<.01) and recurrence (P<.02) of PTC in children and adolescents. Most predictors, unfortunately, are only identified post-operatively by histopathologic examination: Just a small part of them can be pre-operatively detected with a low-sensitivity neck ultrasonography. In PTC patients with pre-operative predictors, we suggest an accurate pre- and intra-operative evaluation of CC and/or LC to find suspicious lymph nodes. The presence of LNM in CC has an impact on disease/progression/relapse-free survival. We suggest performing RAI therapy and an accurate follow-up for pediatric patients with only post-operative predictors.

Significance of Subcategory Atypia of Undetermined Significance/Follicular Lesion of Undetermined Significance Showing Both Cytologic and Architectural Atypia in Thyroid Aspiration Cytology

Objective: The Bethesda System for Reporting Thyroid Cytopathology is now widely used as the standard reporting system for fine-needle aspiration cytology (FNAC). Recently, several studies have attempted to subcategorize the atypia of undetermined significance (AUS)/follicular lesion of undetermined significance (FLUS) category. We aimed to analyze the significance of a subcategory of AUS/FLUS showing both cytologic and architectural atypia (AUS/FLUS-C&A). Study Design: From April 2011 to May 2014, 18,091 patients underwent FNAC at Samsung Medical Center. For those patients we analyzed the clinical significance of the subcategory AUS/FLUS-C&A. Results: One hundred and sixty-three patients were diagnosed as AUS/FLUS-C&A. Of 71 cases with subsequent histologic confirmation, 47 (66.2%) were diagnosed with papillary thyroid carcinoma (PTC). Of the 47 PTC cases, 32 (68.1%) were follicular variant-PTC. A significant difference in the PTC rate (58.3 vs. 82.6%) and PTC size (average: 1.8 and 0.9 cm) was noted between circumscribed lesions and infiltrative lesions on ultrasonography. Conclusion: We demonstrated that the subcategory of AUS/FLUS-C&A has considerable clinical implications and one should be aware of the cytological and ultrasonographic features.

Discrepancy of Papillary Thyroid Carcinoma Sizes Measured by Ultrasonography and Pathology.

To compare the size of papillary thyroid carcinoma on ultrasonography(US)and the actual size measured during histological examination and to discuss the potential causes of such discrepancy. A total of 148 patients with histologically confirmed papillary thyroid carcinoma underwent thyroid surgery in our center from December 2012 to May 2013. Patients were stratified based on the size,morphology,margin,cystic component,and presence of Hashimoto's disease to compare the discrepancy of the US and pathalogical measurements. The mean sizes of the nodules measured by US and pathology were(1.58±0.94)cm and(1.33±0.84)cm,respectively(P=0.000). In 70.9%(105/148)of the nodules,the sizes measured by US were larger than those measured by pathology. In 17.6%(26/148)of the nodules,the sizes measured by US were smaller than those measured by pathology. In 1.1-1.4 cm size subgroup,the difference between mean ultrasound diameter and pathologic diameter was not significant [(1.21±0.11)cm vs.(1.11±0.32)cm,P=0.062]. In 0.1-1.0 cm size subgroup,the mean sizes of the nodules measured by US and pathology were(0.75±0.19)cm and(0.62±0.23)cm,respectively(P=0.000). In ≥1.5 cm size subgroup,the mean sizes of the nodules measured by US and pathology were(2.48±0.70)cm and(2.03±0.81)cm(P=0.000). There is a significant discrepancy between US and pathologic size measurements for papillary thyroid carcinoma. However,for nodules sized 1.1-1.4 cm,the ultrasound and pathologic measurements are more likely to be consistent.

Incidental papillary thyroid carcinoma: diagnostic findings in a series of 287 carcinomas.

The recent increase in the detection of papillary thyroid carcinoma (PTC) has been influenced by the finding of incidental tumours. To this group, carcinomas measuring less than 1 cm (the so-called microcarcinomas) as well as those above 1 cm belong. Analyzing a case series from our own experience, this paper focuses on the current pre-operative diagnostic challenges that can lead to PTC incidental discovery. For this retrospective study, 287 patients with a PTC diagnosis were selected. For each, the following variables were analysed: sex, age, ultrasound (US) appearance, number of thyroid nodules, PTC size, PTC variants and presence of other associated pathology. Pre-operative fine needle aspiration (FNA) results were classified according to the five-tiered SIAPEC system. For 281 patients, the US-guided FNA results were available. Cytohistological correlation was evaluated in terms of FNA sensitivity and false negative rate. An incidental PTC was found in 45.2 % of patients. The majority of these were due to unsuccessful US detection of malignant nodules (103 cases); incorrect cytological diagnosis was responsible for the other 24 cases. The most powerful clinical confounding factors were: multinodular background versus single nodule presentations (p < 0.001) and histotype (follicular vs conventional variant, p < 0.05). Of course, tumour size remains a strongly influential feature on pre-operative diagnosis, with greater difficulties arising for carcinomas <5 mm. Moreover, FNA sensitivity was lower also in large PTCs (>2 cm) due to tumour heterogeneity. Although with limitations related to the tumour's intrinsic features and the thyroid background, US-guided FNA, especially if performed by a dedicated multidisciplinary team, is a powerful diagnostic tool for detecting malignant thyroid nodules. To the state of the art, we propose a practical clinical-pathological cut-off for this procedure, setting it at 5 mm.

Relative sensitivity of thyroid fine‐needle aspiration by tumor type and size

Fine-needle aspiration (FNA) of papillary thyroid carcinoma (PTC) has high sensitivity. Previous studies demonstrated correlation between FNA sensitivity and PTC size, and lower sensitivity for follicular variant of PTC (FVPTC). Data are lacking for other types of thyroid carcinomas. 996 resected thyroid carcinomas at two institutions (6- and 10-year periods) were correlated with FNA diagnoses and clinical and radiologic data to determine sensitivity for each malignancy type. There were 867 PTCs (371 FVPTC), 101 follicular carcinomas (FCs) (31 oncocytic), 16 medullary carcinomas, and 12 poorly differentiated carcinomas (PDCAR). Mean size of classical PTC (CPTC; 1.9 cm) was smaller than FVPTC (2.2 cm), FC (3.0 cm), oncocytic FC (3.0 cm), and PDCAR (2.8 cm) (P<0.003 each), but not medullary carcinoma (1.7 cm) (P=0.45). Sensitivity was higher for CPTC (88%), compared to FVPTC (78%; P<0.0001) and FC (71%; P=0.0006) and was lower for FC than PDCAR (100%; P<0.04). For tumors ≤1.0 cm, FNA sensitivity for CPTC was higher than for FVPTC (P=0.02). For tumors 1.1-2.9 cm, sensitivity for CPTC was better than FVPTC (P=0.0001) and FC (P=0.0008). Between size groups, only CPTC showed a significant change with decreased sensitivity for tumors ≥3.0 cm (P<0.003). FNA is more sensitive for CPTC, PDCAR, and medullary carcinoma. For CPTC, FNA sensitivity is highest for tumors 1.1-2.9 cm. FNA sensitivity is higher for CPTC than FVPTC for nodules <3.0 cm. FNA sensitivity is lower for FC than CPTC and PDCAR.

A missense polymorphism (rs11466653, Met326Thr) of toll-like receptor 10 (TLR10) is associated with tumor size of papillary thyroid carcinoma in the Korean population

Toll-like receptors (TLRs) are important components of innate immune response. The aim of this study was to investigate whether TLR gene cluster (TLR10-TLR1-TLR6) polymorphisms are associated with the etiology of papillary thyroid carcinoma (PTC) and its clinicopathologic characteristics. We recruited 94 PTC patients and 325 control subjects. Genotypes for each SNP were determined by direct sequencing. SNPStats and SPSS 18.0 were used to evaluate odds ratios (ORs), 95 % confidence intervals (CIs), and P values. Multiple logistic regression analyzes of genetic data were performed. The missense SNP rs11466653 was associated with small tumor size (<1 cm) in PTC. The frequency of the rs11466653 T allele was higher in PTC patients with tumors <1 cm in size than in the control group (95.8 vs. 87.2 %; P = 0.021, OR = 0.30, 95 % CI = 0.11-0.83). The T allele of rs11466653 (T/C, Met326Thr) in TLR10 may be a risk factor for the development of tumors in PTC in the Korean population.

BRAFV600E mutation in fine‐needle aspiration aspirates: Association with poorer prognostic factors in larger papillary thyroid carcinomas

Recent studies have shown that BRAF(V600E) mutation is associated with poor prognostic factors in papillary thyroid carcinoma (PTC). However, there are no studies about the association of the BRAF(V600E) mutation with poor prognostic factors according to tumor size in PTC. We investigated the prevalence of the BRAF(V600E) mutation and its association with prognostic factors according to tumor size of PTC. BRAF(V600E) mutation status was assessed in thyroid fine-needle aspiration (FNA) specimens from 605 patients before thyroidectomy for PTC, and its association with postoperative clinicopathologic factors was evaluated. The overall prevalence of the BRAF(V600E) mutation was 67%, and larger tumors more often had the BRAF(V600E) mutation (p for trend < .05). The BRAF(V600E) mutation was significantly associated with male sex, tumor size, extrathyroidal invasion, nodal metastasis, and advanced tumor stage (p < .05). There was a significant size-dependent relationship between the presence of the BRAF(V600E) mutation and extrathyroidal invasion, nodal metastasis, and advanced tumor stage (p for trend < .05). The prevalence of the BRAF(V600E) mutation increased with increased tumor size. Preoperative FNA-detected BRAF(V600E) mutation was associated with poor prognostic factors, and the association was stronger in larger tumors.

Nodule heterogeneity as shown by size differences between the targeted nodule and the tumor in thyroidectomy specimen

Missed papillary thyroid carcinoma (PTC) diagnoses on fine-needle aspiration (FNA) can result from many causes. To the authors' knowledge, the issue of whether the detection of PTC is correlated with nodule heterogeneity has not been studied to date. The authors identified all thyroidectomy specimens with a diagnosis of PTC that had undergone at least 1 prior FNA in the study institution between 1998 and 2003. The tumor size at the time of the resection, the ultrasound (US)-determined nodule size, and other parameters were compared between the 2 groups in which PTC was or was not diagnosed on FNA. Of a total of 89 specimens, 47 were diagnosed on FNA with an average tumor size of 1.7 cm and an US-determined nodule size of 2.1 cm (a difference of 0.4 cm). Forty-two specimens with a smaller average tumor size of 0.9 cm (P < .0001) and a US-determined nodule size of 2.4 cm (a difference of 1.5 cm) were missed. The differences with regard to the US-determined nodule size and tumor size between the 2 groups were significant (0.4 cm vs 1.5 cm; P < .0001). In the missed group, 29 specimens were found to have PTC foci that measured < or = 1.0 cm and 26 had a reasonable size difference (RSD; defined as a PTC size outside the range of +/-50% of the US-determined nodule size) as the indicator of the mixed nature of nodules targeted for FNA, whereas in the diagnostic group, 9 foci measured < or = 1.0 cm and 6 had RSD. There was no cytologic evidence with which to render a diagnosis of PTC on further review in the missed group. The major reason for a missed diagnosis of PTC on FNA is because of inadequate tumor sampling due to the heterogeneity of the nodule targeted for FNA. This is illustrated by the RSD noted between the targeted nodule and the actual PTC tumor focus in the resection specimen.

The expression of vascular endothelial growth factor and the type 1 vascular endothelial growth factor receptor correlate with the size of papillary thyroid carcinoma in children and young adults.

Vascular endothelial growth factor (VEGF) is essential for the growth of many solid tumors, but there are little data regarding VEGH in childhood thyroid cancers. We examined the relationships between VEGF, the type 1 VEGF receptor (FLT-1) and clinical outcome for a group of thyroid cancers in children and young adults. The expression of VEGF and FLT-1 were determined by immunohistochemistry using archival, paraffin-embedded thyroid tissue blocks and compared with the retrospective clinical outcome for each patient. The study included 67 children and young adults with papillary thyroid carcinoma (PTC, n = 42), follicular thyroid carcinoma (FTC, n = 8), benign lesions (n = 15), or controls (n = 2). VEGF expression was greater in PTC (mean intensity 2.23 +/- 0.25, p = 0.002) and FTC (2.8 +/- 0.73, p = 0.01) than benign lesions (1.0 +/- 0.27), and correlated with PTC size (r = 0.42, p = 0.008). FLT-1 expression was greater in PTC (mean intensity 2.8 +/- 0.17) than FTC (1.9 +/- 0.25, p = 0.015) and benign lesions (1.7 +/- 0.32, p = 0.002); and correlated with PTC size (r = 0.41, p = 0.01) as well as VEGF expression (r = 0.52, p = 0.002). Recurrent disease developed exclusively in patients with PTC which expressed VEGF (7/28, 95% CI 10.6%-44.2%). PTC that did not express VEGF (0/8, 95% CI = 0%-31.2%) did not recur; however, the difference was not statistically significant (p = 0.15). We conclude that the expression of VEGF and FLT-1 are directly correlated with the size of PTC in children and young adults.