Tumour growth rate of follicular thyroid carcinoma is not different from that of follicular adenoma

Ultrasound and histopathological assessment of benign, borderline, and malignant thyroid tumors in pediatric patients: an illustrative review and literature overview

Background

The risk of malignancy in thyroid nodules is higher in children than in adults, often necessitating a more aggressive endocrine and surgical approach. However, given that not all solid thyroid nodules are malignant, a more conservative approach may also be appropriate in certain cases.

Objective

This study aims to present an illustrative analysis of the pathological foundations underlying the sonographic appearance of benign, borderline, and malignant thyroid nodules in the pediatric population at a single tertiary thyroid center.

Methods

A total of 47 well-documented pediatric patients referred for thyroid surgery between 2010 and 2023 were analyzed. This retrospective assessment included an examination of demographic data, hormonal profiles, ultrasound findings, and histopathology reports.

Results

Ultrasound and histopathology of thyroid nodules provided insights into subgroup differentiation. Benign nodules like dyshormonogenetic goiter showed solid hypoechoic features on ultrasound and dense fibrosis on histopathology, while thyroid follicular nodular disease exhibited isoechoic nodules with halos, histologically revealing dilated follicles. In borderline tumors, well-differentiated tumor of uncertain malignant potential (WDT-UMP) nodules were hypo/hyperechoic with occasional capsular invasion, resembling papillary thyroid carcinoma (PTC) features histologically. Non-invasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP) appeared as well-defined hypoechoic nodules with a hypoechoic rim, with histology showing follicular architecture and PTC nuclear features, but no invasion. Follicular tumor of uncertain malignant potential (FT-UMP) displayed hypo/hyperechoic patterns and indistinct borders, with uncertain capsular invasion and no PTC nuclear features. Malignant lesions showed distinct patterns: PTC as hypoechoic, irregular nodules with mixed vascularization, follicular thyroid carcinoma as large, hyperechoic nodules with invasive features, and poorly differentiated thyroid carcinoma (PDTC) as heterogeneous hypoechoic masses.

Conclusion

Because of the significant overlap in sonographic features among benign, borderline, and certain malignant thyroid lesions in pediatric patients, ultrasonography alone is insufficient for accurate risk stratification. This overlap necessitates referrals for fine-needle aspiration biopsy (FNAB) in children more frequently than in adults. Future studies utilizing artificial intelligence (AI) to predict clinical outcomes in thyroid nodule diagnostics may offer new advancements, particularly given the increasing number of pediatric patients with solid thyroid lesions.

Prognostic Factors for Cancer-Specific Survival and Disease-Free Interval in 130 Patients with Follicular Thyroid Carcinoma: Single Institution Experience

BACKGROUND

Follicular thyroid carcinoma (FTC) is categorized into three groups: minimally invasive FTC (MIFTC), encapsulated angioinvasive FTC (EAIFTC), and widely invasive FTC (WIFTC). FTC is the second most common type of thyroid tumor, though it remains relatively rare in the general population. This study aimed to examine the prognosis and prognostic factors in patients with follicular thyroid carcinoma.

METHODS

Data were obtained from a tertiary referral center for 130 FTC patients, covering the period from 1995 to 2020. Clinical data included demographic characteristics, tumor features, type of surgery, tumor recurrence, and vital status. Descriptive statistical methods, Kaplan-Meier survival curves, and Cox proportional hazard regression were used for statistical analysis to identify independent predictors.

RESULTS

Distant metastases occurred in 12 patients during the follow-up period. The 5-year, 10-year, 15-year, and 20-year cancer-specific survival (CSS) rates were 98.1%, 92.3%, 83.5%, and 79.8%, respectively. Independent unfavorable prognostic factors for CSS included widely invasive tumor type (hazard ratio [HR] 3.63, 95% CI 1.29-10.18), multifocality (HR 6.7, 95% CI 1.37-32.72), and presence of distant metastases (HR 2.29, 95% CI 1.08-4.84). When disease-free interval (DFI) was considered, the 5-year, 10-year, 15-year, and 20-year rates were 92.3%, 85.3%, 82.0%, and 76.6%, respectively. Independent unfavorable prognostic factors for DFI were widely invasive tumor type (HR 2.53, 95% CI 1.02-6.28) and tumor multifocality (HR 7.69, 95% CI 1.07-55.17).

CONCLUSIONS

The 10-year survival rate for patients with FTC is relatively favorable. Factors associated with poorer prognosis include the presence of distant metastases, WIFTC, and multifocality. Factors linked to disease recurrence are WIFTC and multifocality.

CTC, ctDNA, and Exosome in Thyroid Cancers: A Review

Thyroid cancer has become more common in recent years all around the world. Many issues still need to be urgently addressed in the diagnosis, treatment, and prognosis of thyroid cancer. Liquid biopsy (mainly circulating tumor DNA (ctDNA), circulating tumor cells (CTCs), and circulating exosomes) may provide a novel and ideal approach to solve these issues, allows us to assess the features of diseases more comprehensively, and has a function in a variety of malignancies. Recently, liquid biopsy has been shown to be critical in thyroid cancer diagnosis, treatment, and prognosis in numerous previous studies. In this review, by testing CTCs, ctDNA, and exosomes, we focus on the possible clinical role of liquid biopsy in thyroid cancer, including diagnostic and prognostic biomarkers and response to therapy. We briefly review how liquid biopsy components have progressed in thyroid cancer by consulting the existing public information. We also discuss the clinical potential of liquid biopsy in thyroid cancer and provide a reference for liquid biopsy research. Liquid biopsy has the potential to be a useful tool in the early detection, monitoring, or prediction of response to therapies and prognosis in thyroid cancer, with promising clinical applications.

Sonographic Features Differentiating Follicular Thyroid Cancer from Follicular Adenoma-A Meta-Analysis

Simple Summary

The risk of thyroid malignancy assessment may include certain ultrasound features. The analysis is lacking for the differentiation of follicular thyroid adenomas and cancers (FTAs and FTCs). Our meta-analysis aimed to identify sonographic features suggesting malignancy in the case of follicular lesions, potentially differentiating FTA and FTC. Based on twenty studies describing sonographic features of 10,215 nodules, we found that the most crucial feature associated with an increased risk of FTC were tumor protrusion (odds ratios—OR = 10.19), microcalcifications or mixed type of calcifications: 6.09, irregular margins: 5.11, marked hypoechogenicity: 4.59, and irregular shape: 3.6.

Abstract

Certain ultrasound features are associated with an increased risk of thyroid malignancy. However, they were studied mainly in papillary thyroid cancers (PTCs); these results cannot be simply extrapolated for the differentiation of follicular thyroid adenomas and cancers (FTAs and FTCs). The aim of our study was to perform a meta-analysis to identify sonographic features suggesting malignancy in the case of follicular lesions, potentially differentiating FTA and FTC. We searched thirteen databases from January 2006 to December 2020 to find all relevant, full-text journal articles written in English. Analyses assessed the accuracy of malignancy detection in case of follicular lesions, potentially differentiating FTA and FTC included the odds ratio (OR), sensitivity, specificity, positive and negative predictive values. A random-effects model was used to summarize collected data. Twenty studies describing sonographic features of 10,215 nodules met the inclusion criteria. The highest overall ORs to increase the risk of malignancy were calculated for tumor protrusion (OR = 10.19; 95% confidence interval: 2.62–39.71), microcalcifications or mixed type of calcifications (coexisting micro and macrocalcifications): 6.09 (3.22–11.50), irregular margins: 5.11 (2.90–8.99), marked hypoechogenicity: 4.59 (3.23–6.54), and irregular shape: 3.6 (1.19–10.92). The most crucial feature associated with an increased risk of FTC is capsule protrusion, followed by the presence of calcifications, irrespectively of their type.

Surgical indications and clinical management of benign and malignant follicular thyroid tumors: An algorithmic-based approach

The present study retrospectively reviewed the treatment courses and results of patients with follicular thyroid tumors, including carcinomas. In the 5 year study period from April 2015 to March 2020, 797 patients with differentiated thyroid carcinoma and 128 patients with follicular tumors (FTs) received surgery or treatment for distant metastases and recurrence at the Kanagawa Cancer Center (Japan). Of these patients, 73 that were diagnosed with follicular thyroid carcinoma (FTC) were included in the present study. An algorithm used for the application of treatment strategies was assessed. The aim of the present study was to examine patients with FT or FTC who were treated at the Kanagawa Cancer Center to devise appropriate treatment strategies and to evaluate the various treatment outcomes of FTC. Pre-diagnostic serum thyroglobulin and thyroid stimulating hormone levels, follow-up and overall survival (OS) were investigated in the present study. The results revealed that OS was significantly increased in patients with minimally invasive follicular thyroid cancer (MIFTC) compared with widely invasive follicular thyroid cancer (WIFTC) (log-rank test, P=0.017). Additionally, OS was significantly higher in patients without distant metastasis at the first consultation compared with those initially diagnosed with distant metastasis (log-rank test, P=0.023). Although all patients without distant metastasis at the first consultation and those with MIFTC are alive, the 10-year survival rates were 75.3% for patients with WIFTC and 75.6% for those with distant metastasis at the first consultation. The results of the present study suggested that the prognosis of WIFTC was the worst among patients with FTC and distant metastasis, and that total thyroidectomy surgery and radioactive iodine treatment are essential. Additionally, if the disease progresses, prompt inclusion of tyrosine kinase inhibitor therapy is necessary.

Development and Validation of a Diagnostic Nomogram for the Preoperative Differentiation Between Follicular Thyroid Carcinoma and Follicular Thyroid Adenomas

OBJECTIVE

The aim of the study was to construct and validate a nomogram for differentiating follicular thyroid carcinoma (FTC) from follicular thyroid adenoma (FTA).

METHODS

Two hundred patients with pathologically confirmed thyroid follicular neoplasms were retrospectively analyzed. The patients were randomly divided into a training set (n = 140) and validation set (n = 60). Baseline data including demographics, CT (computed tomography) signs, and radiomic features were analyzed. Predictive models were developed and compared to build a nomogram. The predictive effectiveness of it was evaluated by the area under receiver operating characteristic curve (AUC).

RESULTS

The CT model, radiomic model and combination model showed excellent discrimination (AUCs [95% confidence interval] = 0.847 [0.766-0.928], 0.863 [0.746-0.932], 0.913 [0.850-0.975]). The nomogram based on the combination model showed remarkable discrimination in the training and validation sets. The calibration curves suggested good consistency between actual observation and prediction.

CONCLUSIONS

This study proposed a nomogram that can accurately and intuitively predict the malignancy potential of follicular thyroid neoplasms.

MiRNA let-7 from TPO(+) Extracellular Vesicles is a Potential Marker for a Differential Diagnosis of Follicular Thyroid Nodules

BACKGROUND

The current approaches to distinguish follicular adenomas (FA) and follicular thyroid cancer (FTC) at the pre-operative stage have low predictive value. Liquid biopsy-based analysis of circulating extracellular vesicles (EVs) presents a promising diagnostic method. However, the extreme heterogeneity of plasma EV population hampers the development of new diagnostic tests. We hypothesize that the isolation of EVs with thyroid-specific surface molecules followed by miRNA analysis, may have improved diagnostic potency.

METHODS

The total population of EVs was isolated from the plasma of patients with FA (n = 30) and FTC (n = 30). Thyroid peroxidase (TPO)-positive EVs were isolated from the total populations using immune-beads. The miRNA from the TPO(+)EVs obtained from the plasma of FA and FTC patients was assayed by RT-PCR. The diagnostic potency of the selected miRNAs was estimated by the receiver operating characteristic (ROC) analysis.

RESULTS

TPO(+)EVs can be efficiently isolated by immunobeads. The analysis of Let-7 family members in TPO(+)EVs allows one to distinguish FA and FTC with high accuracy (area under curve defined by ROC = 0.77-0.84).

CONCLUSION

The isolation of TPO(+)EVs, followed by RT-qPCR analysis of Let-7 family members, may present a helpful approach to manage follicular nodules in the thyroid gland.

Conventional ultrasound characteristics, TI-RADS category and shear wave speed measurement between follicular adenoma and follicular thyroid carcinoma

The purpose of the study was to explore the differences of conventional ultrasound characteristics, thyroid imaging reporting and data system (TI-RADS) category and shear wave speed (SWS) measurement between follicular adenoma (FA) and follicular thyroid carcinoma (FTC). Twenty-eight FTCs and 67 FAs proven by surgery were retrospectively included for analysis. Conventional ultrasound and point-shear wave elastography (p-SWE) were performed in all of the included patients. The ultrasound features, American Thyroid Association (ATA) TI-RADS category and American College of Radiology (ACR) TI-RADS category, SWS measurement were compared between the two groups. Receiver operating characteristic (ROC) curve was performed and area under ROC curve (AUC) was obtained for significant features. There were no statistical differences in mean age (46.9±15.7years vs. 48.6±13.6years, P = 0.639), gender (9 males, 32.1% vs. 18 males, 29.0%, P = 0.766) and mean diameter (28.3±16.2 mm vs. 33.8±11.9 mm, P = 0.077) between FTCs and FAs. Hypoechogenicity, lobulated or irregular margin, macrocalcification were more common in FTCs than FAs (all P < 0.05). Mean SWS of FTCs (2.29±0.64 m/s) was slightly higher than that of FAs (1.94±0.68 m/s) (P = 0.023). The AUCs were 0.655, 0.744, and 0.744 with the cut-off SWS≥1.89 m/s, ACR TI-RADS category 4 and intermediate suspicion of ATA TI-RADS category. The sensitivity and AUC were 82.1% and 0.812 with combined ultrasound features of hypoechogenicity, lobulated or irregular margin and macrocalcification. In Conclusion, SWS measurement and TI-RADS categories were useful for the identification of FTCs from FAs.

Growth rates of malignant and benign thyroid nodules in an ultrasound follow-up study: a retrospective cohort study

Background

Thyroid nodules are frequently detected by cervical ultrasound examinations. In follow-up studies, malignant as well as benign nodules may exhibit an increase in size.

The objective of our investigation was to test whether histologically determined malignant and benign thyroid nodules show differences in growth rates above a defined significance level.

Methods

A retrospective ultrasound cohort follow-up study from 4 to 132 months included 26 patients with differentiated carcinomas and 26 patients with adenomas of the thyroid gland. Significance levels were determined by intra- and interobserver variations of volumetric measurements in 25 individuals.

Results

Intra- and interobserver volumetric measurements were highly correlated (r = 0.99 and r = 0.98, respectively), with variations of 28 and 40%, respectively. The growth rates of malignant and benign nodules did not show differences with respect to two sonographic measurements (d = − 0.04, 95%CI(P): 0.41–0.85, P = 0.83). Using shorter increments and multiple measurements, growth rates of malignant nodules revealed significantly higher values (d = 0.16, 95%CI(P): 0.02–0.04, P = 0.039).

Conclusions

The growth rates of benign and malignant thyroid nodules do not appear to differ using two sonographic volumetric measurements. However, due to temporal changes in cellular proliferation and arrest, malignant nodules may exhibit higher growth rates with multiple assessments and shorter increments.

Determining Whether Tumor Volume Doubling Time and Growth Rate Can Predict Malignancy After Delayed Diagnostic Surgery of Follicular Neoplasm

Background: Tumor volume doubling time (TVDT) is considered as a dynamic indicator of tumor growth and progression. We aimed to clarify whether TVDT should be considered in the cytological diagnosis of follicular neoplasms (FNs). Methods: This retrospective cohort study included 100 consecutive FN patients with a TVDT >1 year for whom surgical resection was delayed for >1 year. Changes in tumor volume and the TVDT of each nodule were calculated by serial neck ultrasonography (US) over a median follow-up of 50 months. Results: Among 100 surgically resected FNs, 58 (58%) were benign and 42 (42%) were malignant tumors. At the 5-year follow-up, most FN nodules showed volume increases of >50%, accounting for 65% of benign and 62% of malignant nodules. No significant difference was observed in tumor growth rates and time to a >50% increase in tumor volume between benign and malignant nodules (p = 0.299 and p = 0.378, respectively). The calculated TVDT and a >50% volumetric increase showed a linear relationship with a high concordance (R² = 0.883; p < 0.001). The risk of malignancy was not significantly associated with TVDT (relative risk = 1.00; [95% confidence interval 0.99-1.01]; p = 0.784). Even when US features were considered, no significant association was found between TVDT and the risk of malignancy. Conclusions: The size of most FNs increased exponentially with time; the tumor growth rates of benign and malignant nodules were similar. Despite the usefulness of TVDT as an indicator of growing velocity of FN nodules, TVDT could not predict malignancy in FNs. Clinical surveillance based on the growth of thyroid nodules categorized as FNs on serial neck US does not predict the risk of malignancy.

Tumor Growth Rate Does Not Predict Malignancy in Surgically Resected Thyroid Nodules Classified as Bethesda Category III with Architectural Atypia

BACKGROUND

It is unknown whether the growth of thyroid nodules with a Bethesda category III cytology (atypia of undetermined significance [AUS]) is predictive of malignancy, especially in cases with architectural atypia (AUS-A). This study evaluated whether tumor growth rates can help distinguish malignant from benign nodules in the AUS-A subcategory.

METHODS

This retrospective, single-center cohort study included 172 patients who underwent diagnostic thyroid surgery because of a nodule with a cytological diagnosis of AUS-A. The growth kinetics of nodules was assessed by serial preoperative neck ultrasonography over a median follow-up of 52.6 months (range 12.7-198.3 months).

RESULTS

Pathologic examinations showed that 112 (65%) and 60 (35%) patients had benign and malignant nodules, respectively. The largest diameter and volume of both benign and malignant nodules increased gradually (p < 0.001). However, there was no significant difference in the growth rates of benign and malignant nodules based on the largest diameter (p = 0.132) and volume (p = 0.200). The time to tumor growth curves and estimated median time to significant tumor growth from baseline were not significantly different in malignant nodules compared to benign nodules (p = 0.458 and p = 0.568, respectively). The relative risk (RR) of malignancy of growing and stable nodules did not differ significantly based on the largest diameter (RR = 0.5; p = 0.064) and volume (RR = 0.9; p = 0.748).

CONCLUSIONS

The size of thyroid nodules classified as AUS-A increased linearly, regardless whether these nodules were benign or malignant. These results suggest that growth kinetics on serial preoperative neck ultrasonography cannot predict malignancy in the AUS-A subcategory.