Indeterminate thyroid nodules in the era of molecular genomics

Thermal ablation for Bethesda III and IV thyroid nodules: current diagnosis and management

The diagnosis and management of Bethesda III and IV thyroid nodules remain clinical dilemmas. Current guidelines from academic societies suggest active surveillance or diagnostic lobectomy. However, the extent of surgery is often inappropriate, and a considerable percentage of patients experience under- or over-treatment. Thermal ablation has gained popularity as a safe and effective alternative treatment option for benign thyroid nodules. This review explores the feasibility of thermal ablation for Bethesda III or IV thyroid nodules, aiming to preserve the thyroid organ and avoid unnecessary surgery. It emphasizes individualized management, the need to consider factors including malignancy risk, clinical characteristics, and sonographic features, and the importance of supplemental tests such as repeat fine needle aspiration cytology, core needle biopsy, molecular testing, and radioisotope imaging.

The role of the ThyGeNEXT oncogene panel used in combination with the expanded miRNA panel ThyraMIRv2 in Indeterminate thyroid nodules: A large, blinded, real-world, observational study

BACKGROUND

Molecular analysis of fine-needle aspiration biopsies (FNAB) improves the diagnostic accuracy of cytologically indeterminate thyroid nodules (ITNs). Recently, the use of MPTXv2 has been shown to further improve the accuracy of risk stratification of ITNs.

METHODS

A total of 338 patient samples with atypia of undetermined significance (n = 258) or follicular neoplasm (n = 80) cytology diagnosis and corresponding surgical outcomes or clinical follow-up, collected between 2016 and 2020 were included [Correction added on 19 June 2024, after first online publication: In the preceding sentence, the n values 260 and 78 have been changed to 258 and 80, respectively.]. All samples underwent multiplatform testing (MPTXv1), which includes an oncogene panel (ThyGeNEXT®) plus a microRNA risk classifier (ThyraMIR®). A blinded, secondary analysis was performed to assess the added utility of MPTXv2 (ThyraMIR®v2). The average length of follow-up for the surveillance group (n = 248) was 30 months.

RESULTS

Sensitivity at moderate threshold was 96% and specificity at positive threshold was 99% for MPTXv2. At 14% disease prevalence, the negative predictive value at the moderate threshold was 99% and the positive predictive value at the positive threshold was 89% for MPTXv2. MPTXv2 had fewer patients classified into the moderate-risk group than MPTXv1, which was statistically significant (p < .001). Using surgical resection, the gold standard for outcomes, MPTXv2 showed a statistically greater area under the curve (p = .028) than MPTXv1, demonstrating greater accuracy for MPTXv2.

CONCLUSION

Both test versions demonstrated robust performance with low false-positive molecular results. Data suggest that incorporation of MPTXv1, and more recently MPTXv2, into clinical practice within our healthcare network resulted in improved accuracy of ITN risk stratification.

Artificial intelligence in the diagnosis of thyroid cancer: Recent advances and future directions

The diagnosis and management of thyroid cancer is fraught with challenges despite the advent of innovative diagnostic, surgical, and chemotherapeutic modalities. Challenges like inaccuracy in prognostication, uncertainty in cytopathological diagnosis, trouble in differentiating follicular neoplasms, intra-observer and inter-observer variability on ultrasound imaging preclude personalised treatment in thyroid cancer. Artificial intelligence (AI) is bringing a paradigm shift to the healthcare, powered by quick advancement of the analytic techniques. Several recent studies have shown remarkable progress in thyroid cancer diagnostics based on AI-assisted algorithms. Application of AI techniques in thyroid ultrasonography and cytopathology have shown remarkable impro-vement in sensitivity and specificity over the traditional diagnostic modalities. AI has also been explored in the development of treatment algorithms for indeterminate nodules and for prognostication in the patients with thyroid cancer. The benefits of high repeatability and straightforward implementation of AI in the management of thyroid cancer suggest that it holds promise for clinical application. Limited clinical experience and lack of prospective validation studies remain the biggest drawbacks. Developing verified and trustworthy algorithms after extensive testing and validation using prospective, multi-centre trials is crucial for the future use of AI in the pipeline of precision medicine in the management of thyroid cancer.

An innovative synthetic support for immunocytochemical assessment of cytologically indeterminate (Bethesda III) thyroid nodules

Background

Fine needle aspiration (FNA) is the procedure of choice in the evaluation of thyroid nodules. Nodules with indeterminate cytological categories, Bethesda III and IV, pose challenges in clinical practice and are frequently submitted to diagnostic surgery. CytoFoam Core (CFCS) uses an absorbent foam device inserted into the needle hub to collect the cytological sample aspirated during FNA. Specimen is formalin-fixed and paraffin-embedded.

Aim of the study

Assessing diagnostic efficacy of CFCS, compared to traditional cytology, in re-evaluating thyroid nodules classified as Bethesda III, using post-surgical histology as reference standard.

Method

Retrospective study on 89 patients with a first indeterminate cytological report who were referred to the Department of Endocrinology of Regina Apostolorum Hospital (Albano L. Rome, Italy) for a second FNA. FNA was performed after at least one month under ultrasound guidance with a 23G needle according to the established procedure. During the second procedure, both traditional cytological (TC) smears and a single-pass CFCS specimen were obtained for each patient. On CFCS samples immunocytochemical staining for Galectin-3, HBME-1, and CK-19 was also performed. 51 patients eventually underwent surgery, and their histological diagnoses were compared to the TC and CFCS reports. Four parameters were evaluated: inadequacy rate, rate of persistent indeterminate (Bethesda III and IV) reports, rate of malignancy in persistently indeterminate nodules, and rate of cancer in lesions cytologically classified as malignant.

Results

Non-diagnostic samples were 6 (11.8%) in TC vs 3 (5.9%) in CFCS (p=0.4). Persistent indeterminate samples were 31 (60.8%) in TC vs 19 (37.2%) in CFCS (p=0.01). Rate of malignancy in persistently indeterminate nodules was 8/19 (42.1%) in CFCS vs 9/31 (29%) in TC group (p=0.3). Nine/51 (17.6%) samples were classified as benign by TC vs 21/51 (41.2%) samples by CFCS (p<0.01). All nodules resulted benign at post-surgical evaluation. Five/51 (9.8%) samples were classified as suspicious for malignancy/malignant in TC group against 8/51 (15.7%) samples in CFCS (p=0.5). Post-surgical evaluation confirmed malignancy in all these cases.

Conclusion

CFCS demonstrated greater diagnostic accuracy than TC in repeat FNA assessment of cytologically indeterminate nodules. CFCS increased the conclusive diagnosis rate and decreased the number of cytologically indeterminate cases.

Prospects of Testing Diurnal Profiles of Expressions of TSH-R and Circadian Clock Genes in Thyrocytes for Identification of Preoperative Biomarkers for Thyroid Carcinoma

Thyroid Nodules (TN) are frequent but mostly benign, and postoperative rate of benign TN attains the values from 70% to 90%. Therefore, there is an urgent need for identification of reliable preoperative diagnosis markers for patients with indeterminate thyroid cytology. In this study, an earlier unexplored design of research on preoperative biomarkers for thyroid malignancies was proposed. Evaluation of reported results of studies addressing the links of thyroid cancer to the circadian clockwork dysfunctions and abnormal activities of Thyroid-Stimulating Hormone (TSH) and its receptor (TSH-R) suggested diagnostic significance of such links. However, there is still a gap in studies of interrelationships between diurnal profiles of expression of circadian clock genes and TSH-R in indeterminate thyroid tissue exposed to different concentrations of TSH. These interrelationships might be investigated in future in vitro experiments on benign and malignant thyrocytes cultivated under normal and challenged TSH levels. Their design requires simultaneous measurement of diurnal profiles of expression of both circadian clock genes and TSH-R. Experimental results might help to bridge previous studies of preoperative biomarkers for thyroid carcinoma exploring diagnostic value of diurnal profiles of serum TSH levels, expression of TSH-R, and expression of circadian clock genes.

Update on the Evaluation of Thyroid Nodules

Thyroid nodules (TN) are prevalent in the general population and represent a common complaint in clinical practice. Most are asymptomatic and are associated with a 7%-15% risk of malignancy (1). Methods: PubMed and Medline were searched for articles with a focus on the epidemiology, diagnosis, and management of TN over the past 5 y. Results: The increase in frequency of imaging has led to a rise in the incidence of incidentally diagnosed TN. The initial evaluation of a TN includes assessing thyroid function, clinical risk factors, and neck imaging. Ultrasound remains the gold standard for assessing TN morphology, and biopsy is the standard method for determining whether a TN is benign. Recently published risk stratification systems using morphologic characteristics on ultrasonography have been effective in reducing the number of unnecessary biopsies. Advances in molecular testing have reduced the number of surgical procedures performed for diagnostic purposes on asymptomatic TN with indeterminate cytology. Scintigraphy is the first-line study for assessing a hyperfunctioning nodule. Many TN can be followed clinically or with serial ultrasound after the initial diagnosis. Surgical intervention is warranted when local symptoms are present, in patients with clinical risk factors, as well as in most situations with malignant cytology. Active surveillance is an option in cases of micropapillary thyroid cancer. Emerging nonsurgical approaches for treating TN include ethanol ablation for TN; sclerotherapy for thyroid cysts; and thermal techniques, such as radiofrequency ablation, laser ablation, microwaves, and high-intensity focused ultrasound. Conclusion: Most TN are benign and can be safely monitored. The indications for biopsy and frequency of imaging should be tailored on the basis of risk stratification. Treatment options should be individualized for each patient's particular situation. Active surveillance should be considered in certain cases of papillary microcarcinoma.

ESMO recommendations on the standard methods to detect RET fusions and mutations in daily practice and clinical research

Aberrant activation of RET is a critical driver of growth and proliferation in diverse solid tumours. Multikinase inhibitors (MKIs) showing anti-RET activities have been tested in RET-altered tumours with variable results. The low target specificity with consequent increase in side-effects and off-target toxicities resulting in dose reduction and drug discontinuation are some of the major issues with MKIs. To overcome these issues, new selective RET inhibitors such as pralsetinib (BLU-667) and selpercatinib (LOXO-292) have been developed in clinical trials, with selpercatinib recently approved by the Food and Drug Administration (FDA). The results of these trials showed marked and durable antitumour activity and manageable toxicity profiles in patients with RET-altered tumours. The European Society for Medical Oncology (ESMO) Translational Research and Precision Medicine Working Group (TR and PM WG) launched a collaborative project to review the available methods for the detection of RET gene alterations, their potential applications and strategies for the implementation of a rational approach for the detection of RET fusion genes and mutations in human malignancies. We present here recommendations for the routine clinical detection of targetable RET rearrangements and mutations.

Thyroid Lobectomy for Low to Intermediate Risk Differentiated Thyroid Cancer

Simple Summary

Total thyroidectomy used to be recommended for all thyroid cancers. We now know that some thyroid cancers have a relatively low risk of recurrence. Today, for some of these cancers, depending on the type of tumor, its’ size and other tumor characteristics, a thyroid lobectomy (or hemithyroidectomy) can be performed without increasing the patient’s risk of cancer recurrence. Thyroid lobectomy has the advantages of having less risk of surgical complications and a less frequent need for thyroid hormone replacement therapy. This approach is not optimal for all thyroid cancers, however, and careful tumor and patient selection are necessary. This review explains the rationale and criteria for patient selection for thyroid lobectomy for selected thyroid cancers.

Abstract

Many recent publications and guidelines have promoted a “more is less” approach in terms of treatment for low to intermediate risk differentiated thyroid cancer (DTC), which comprise the vast majority of thyroid cancers: less extensive surgery, less radioactive iodine, less or no thyroid hormone suppression, and less frequent or stringent follow-up. Following this approach, thyroid lobectomy has been proposed as a means of decreasing short- and long-term postoperative morbidity while maintaining an excellent prognosis for tumors meeting specific macroscopic and microscopic criteria. This article will examine the pros and cons of thyroid lobectomy for low to intermediate risk cancers and discuss, in detail, criteria for patient selection and oncological outcomes.

Indeterminate thyroid nodules in the era of molecular genomics

Background

Indeterminate thyroid nodules are diagnosed in up to 30% of fine‐needle aspirations and the risk of malignancy in these cases are highly variable. Consequently, managing these nodules has been a challenge. While a diagnostic thyroidectomy would help clarify the pathology, there is the risk of developing surgical‐related complications for a procedure that may not have been necessary and associated high costs. Genomic testing of indeterminate thyroid nodules may help better guide management.

Methods

We present an unbiased comprehensive review of available molecular testing for classifying indeterminate thyroid nodules, as well as their strengths and limitations, with the objective to allow practitioners to choose the best testing modality for their patients.

Results

Molecular testing of these nodules provided a platform to help distinguish benign versus malignant nodules, providing more confidence to rule in or rule out the likelihood of thyroid cancer in indeterminate nodules.

Conclusion

Genomic testing has evolved to more comprehensive panels to better stratify indeterminate nodules, including Hürthle cell neoplasms and noninvasive follicular neoplasm with papillary‐like nuclear features. Understanding the methodology of each available test improves patient care and reduces unnecessary costs.