Utility of mutational analysis for risk stratification of indeterminate thyroid nodules in a real-world setting.

OBJECTIVE: American Thyroid Association (ATAn) 2015 guidelines recommend repeat fine-needle aspiration with molecular marker profiling (MMP) or diagnostic lobectomy in thyroid nodules yielding atypia of unknown significance/follicular lesion of unknown significance (AUS/FLUS) or follicular neoplasm/suspicious for follicular neoplasm (FN/SFN) cytology. Our objective is to describe the molecular profiles and histological correlates of these cytologically indeterminate nodules (CIN) to aid risk stratification. DESIGN: Retrospective chart review. PATIENTS: Adults with CIN that underwent MMP from 2017 to 2020. MEASUREMENTS: Pearsons' χ2 , Fisher's exact test, nonparametric testing and multiple regression analysis were performed. RESULTS: A total of 89 CIN underwent mutational analysis. Of 55% (n = 49) were Bethesda class III AUS/FLUS and 45% (n = 40) were Bethesda class IV FN/SFN. The US phenotype of a CIN was isoechoic (53%) or hypoechoic (32%) with well-defined margins (98%), absence of calcifications (75%) and mildly increased internal vascularity (70%). A total of 84% and 87% of nodules were classified as mild/moderate or low/intermediate risk per the Thyroid Imaging Reporting and Data System and ATA classifications, respectively. Based on the Thyroseq patient management resource, 6.7% (n = 6) of nodules had a high predicted probability of cancer (≥95%), 41.6% (n = 37) were intermediate probability (40%-94%) and 51.7% (n = 46) were low probability (<40%). MMP revealed positive mutations in 45% (n = 40) of nodules, with 71% demonstrating RAS mutations. Of the nodules that underwent resection (n = 38), 39% (n = 15) had malignant pathology. Increasing the threshold to recommend surgical resection to a Thyroseq predicted probability of cancer to ≥50%, had a 100% sensitivity and 65% specificity for detecting malignant nodules (area under the ROC curve: 0.86). The positive predictive value was 37% and the negative predictive value was 100%. CONCLUSION: US phenotypes of CIN nodules were variable and did not aid in differentiating malignant from benign nodules. Of the CIN nodules with a positive MMP, most were RAS and had a benign pathology. With the exception of high-risk genetic markers for malignancy, the threshold to recommend surgical resection should be raised for CIN. Further studies to improve risk stratification in these nodules are required.

Mutation based approaches to the treatment of anaplastic thyroid cancer.

OBJECTIVE: The treatment of anaplastic thyroid cancer (ATC) has continued to rapidly evolve over time. Increased utilization of novel, personalized therapies based upon the tumour's somatic mutation status has recently been integrated. The aim of this case series is to describe a series of patients that underwent rapid genomic testing upon their diagnosis of ATC, allowing for the early integration of novel therapies. DESIGN: A fast track pathway for genomic tumour analysis of patients with ATC was implemented at a single academic cancer hospital in January of 2020. PATIENTS: All patients were evaluated by head and neck surgery, endocrinology, and medical oncology upon diagnosis of ATC. MEASUREMENTS: Genetic work-up was completed, which prompted a recommendation for dual BRAF/MEK inhibition with dabrafenib and trametinib for tumours with BRAF V600E mutation. For patients whose tumours were BRAF V600E wild-type, pembrolizumab with lenvatinib was offered. RESULTS: A total of four patients were included in this series. Two patients (50%) had tumours that were BRAF V600E positive. Among patients that were BRAF V600E positive, both patients initiated urgent dabrafenib and trametinib dual tyrosine kinase inhibitor (TKI) therapy; with one patient demonstrating near-complete clinical response allowing for posttreatment surgery, while the other demonstrated decreased tumour burden. Among patients who were BRAF V600E wild-type, lenvatinib and pembrolizumab were recommended off-label; one patient demonstrated decreased tumour burden, but developed severe pure red cell aplasia, while the other patient is demonstrating an early clinical response. CONCLUSIONS: The integration of early genomic analysis and personalized neoadjuvant TKI therapy into the treatment of ATC can greatly benefit patient care outcomes and optimize tumour control.

VASCULARITY-TARGETED PERCUTANEOUS ETHANOL INJECTION OF TOXIC THYROID ADENOMAS: OUTCOMES OF A FEASIBILITY STUDY PERFORMED IN THE USA.

Objective: The recommended treatment options for toxic adenoma (TA) in the USA are radioactive iodine ablation and surgical resection, with continued observation for pre-toxic adenoma (PTA). Percutaneous ethanol ablation (PEI) has proven efficacy in the treatment of TA and is widely available in Europe but not in the USA. Methods: Retrospective analysis was performed of all patients who underwent PEI for TA/PTA at the University of Utah, from January 2010 to 2018. Ultrasound-guided PEI, with injections targeting power Doppler-mapped blood vessels within the adenomas, was conducted. Functionality was confirmed using thyroid scintigraphy prior to PEI. Results: Eighteen adults (15 female) underwent PEI. Mean age was 41 ± 13.7 years. Baseline thyroid-stimulating hormone (TSH) was suppressed (0.06 ± 0.09 mU/L), with normal free thyroxine (FT4) 1.43 ± 0.39 ng/dL. Median nodule volume was 5.7 cm3 (interquartile range [IQR], 4.8 to 7.7 cm3). Seventy-eight percent (n = 14) underwent two or less PEI sessions. Median volume of ethanol used was 0.46 mL/mL nodule volume (IQR, 0.3 to 0.6 mL). There was a significant increase in TSH concentrations within the first 3 months after PEI (0.06 ± 0.09 mU/L vs. 1.22 ± 1.88 mU/L; P = .02), with a concomitant significant decrease in FT4 concentrations (1.43 ± 0.39 ng/day vs. 1.13 ± 0.25 ng/day; P<.01). Significant nodular volume reduction was observed following PEI (median 5.7 cm3 [IQR 4.8-7.7 cm3] vs. 2.5 cm3 [IQR 2.0-7.8 cm3]; P<.01). Conclusion: Vascularity-targeted PEI is safe and effective for treating PTA and TA. This unique approach required lower injected alcohol volume and fewer injections for therapeutic success. Abbreviations: ATA = American Thyroid Association; FT4 = free thyroxine; IQR = interquartile range; PD = power Doppler; PEI = percutaneous ethanol injection; PTA = pre-toxic adenoma; RAI = radioactive iodine ablation; RFA = radiofrequency ablation; TA = toxic adenoma; TT3 = total triiodothyronine; US = ultrasound.

Four-Dimensional Computed Tomography for Parathyroid Adenoma Localization: A Pre-Operative Imaging Protocol.

OBJECTIVE: Primary hyperparathyroidism (PHPT) affects approximately 0.86% of the population, with surgical resection as the treatment of choice. A 4D computed tomography (CT) is a highly effective tool in localizing parathyroid adenomas; however, there is currently no defined role for 4D CT when stratified against ultrasonography (USG) and nuclear medicine Technetium Sestamibi SPECT/CT (SES) imaging. STUDY DESIGN: Retrospective Study. SETTING: University Hospital. METHODS: All patients who underwent parathyroidectomy for PHPT between 2014 and 2019 at a single institution were reviewed. Patients who had a 4D CT were included. We compared outcomes of 4D CT as a second line imaging modality to those of USG and SES as first line modalities. An imaging algorithm was proposed based on these findings. RESULTS: There were 84 patients identified who had a 4D CT after unsuccessful first line imaging. A 4D CT localized parathyroid adenoma to the correct quadrant in 64% of cases, and to the correct laterality in 75% of cases. Obese patients had significantly lower rates of adenoma localization with USG (33.4%), compared to non-obese patients (67.5%; P = .006). In determining multigland disease the sensitivity of 4D CT was 86%, while the specificity was 87%. CONCLUSIONS: A 4D CT has impressive rates of accurate localization of parathyroid adenomas; however due to the radiation exposure involved, it should remain a second line imaging modality. PHPT patients should first be evaluated with USG, with 4D CT used if this is unsuccessful and patients are greater than 40 years old, have a high BMI, or are having revision surgery.

Measurement of thyroglobulin by liquid chromatography-tandem mass spectrometry in serum and plasma in the presence of antithyroglobulin autoantibodies.

BACKGROUND: Measurement of serum thyroglobulin (Tg) is used to monitor patients after treatment for differentiated thyroid carcinoma (TC). Difficulty in using Tg as a biomarker of the recurrence of TC in many patients stems from the presence of endogenous anti-Tg autoantibodies (Tg-AAbs), which can interfere with immunoassays (IAs) and cause false-negative results. METHODS: We enriched Tg from serum samples using rabbit polyclonal anti-Tg antiserum and protein precipitation. Unrelated proteins were partially depleted in the process. Enriched proteins were then denatured, reduced, and digested with trypsin after the addition of a winged internal standard peptide. A Tg-specific tryptic peptide was purified by immunoaffinity extraction and analyzed by 2-dimensional LC-MS/MS. Instrument cycle time was 6.5 min per sample. RESULTS: The lower limit of quantification was 0.5 ng/mL (0.76 fmol/mL dimer). Total imprecision of triplicate measurements in serum samples over 5 days was <10%. Comparison with a commercial IA using serum samples free of Tg-AAb (n = 73) showed Deming regression, IA = 1.00 * LC-MS/MS - 2.35, r = 0.982, standard error of the estimate (S(y|x)) = 9.52. In a set of Tg-AAb-positive samples that tested negative for Tg using IA (n = 71), concentrations determined by LC-MS/MS were ≥0.5 ng/mL in 23% of samples (median 1.2, range 0.7-11 ng/mL). CONCLUSIONS: The introduced method has acceptable performance characteristics for use in clinical diagnostic applications. The most substantial disagreement between methods was observed in Tg-AAb-positive samples with concentrations <2 ng/mL (determined with LC-MS/MS). The affinity-assisted enrichment strategy used for Tg in this method should be applicable to other biomarkers that have endogenous autoantibodies.

Dropper method for cytology slide staining: An effective and sustainable approach to eliminating cross contamination.

Cytopathology laboratories must ensure effective measures to prevent cross-contamination during slide staining. As such, slides with high potential for cross-contamination are usually stained separately, by dipping slides into a series of Romanowsky-type stains, with periodic (usually weekly) filtering and replacement of stains used. Our 5-year experience and a validation study of an alternative dropper method is presented. In this method, cytology slides are placed in a staining rack, a small amount of stain is applied to each using a dropper. Because of the small amount of stain used, this dropper method requires no filtering or reuse of stain, eliminating the possibility of cross contamination and reducing the total amount of stain used. In our 5-year experience, we report a complete elimination of cross contamination due to staining, excellent staining quality, and a slight reduction in overall stain expenditure.

Reproductive and gynecological complication risks among thyroid cancer survivors.

PURPOSE: Thyroid cancer is the most rapidly increasing cancer in the USA, affects a young, mostly female population, and has high survival. The aim of this study was to determine if there is an increased risk of reproductive system adverse events or pregnancy complications among women diagnosed with thyroid cancer under the age of 50. METHODS: Up to five female cancer-free individuals were matched to each female thyroid cancer survivor diagnosed before the age of 50 based on birth year, birth state, and follow-up time, within the Utah Population Database. Medical records were used to identify disease diagnoses stratified over three time periods: 0-1, > 1-5, and > 5-10 years after cancer diagnosis. Cox proportional hazards models were used to estimate hazard ratios (HR) with adjustment on matching factors, race, BMI, and Charlson Comorbidity Index. RESULTS: There were 1832 thyroid cancer survivors and 7921 matched individuals. Thyroid cancer survivors had higher rates of having multiple health conditions associated with the gynecological system (15.4% vs. 9.4%) and pregnancy (14.3% vs 9.5%) > 1-5 years after cancer diagnosis. Increased risks persisted > 5-10 years after cancer diagnosis for menopausal disorders (HR = 1.78, 99% CI = 1.37, 2.33) and complications related to pregnancy (HR = 2.13, 99% CI = 1.14, 3.98). Stratified analyses showed these risks remained increased across different treatment types. CONCLUSIONS: There were significant risk increases in reproductive system and pregnancy complications among female thyroid cancer survivors within this study. IMPLICATIONS FOR CANCER SURVIVORS: Although radiation has been linked to reproductive risks in previous studies, we found risks were increased in patients regardless of treatment.

Risk Factors for Cardiovascular Disease Among Thyroid Cancer Survivors: Findings From the Utah Cancer Survivors Study.

Context: Thyroid cancer survivors are at high risk of developing multiple cardiac and vascular conditions as consequence of cancer diagnosis and treatment. However, it is still unclear how the baseline and prognostic factors, as well as cancer treatments, play a role in increasing cardiac and vascular disease risk among thyroid cancer survivors. Objective: To investigate the association between potential risk factors, treatment effects, and cardiovascular disease (CVD) outcomes in thyroid cancer survivors. Design, Setting, Patients: Primary thyroid cancer survivors, diagnosed from 1997 to 2012 (n = 3822), were identified using the statewide Utah Population Database. The medical records were used to ascertain information on risk factors and CVD outcomes. Cox proportional hazards models were used to assess the risk of CVD with baseline demographic data and clinical factors. Results: Among thyroid cancer survivors, age and year at cancer diagnosis, cancer stage, sex, baseline body mass index, baseline comorbidities, and TSH suppression therapy were significantly associated with CVD risk 1 to 5 years after cancer diagnosis. Patients who were male, overweight or obese, older at cancer diagnosis, and diagnosed with cancer since 2005 had an increased risk of CVD compared with patients who were female, had a normal body mass index, were younger at cancer diagnosis, and diagnosed with cancer from 1997 to 1999. Administration of TSH suppression therapy, distant metastases at cancer diagnosis, and a higher Charlson comorbidity index score were associated with an increased CVD risk among thyroid cancer survivors. Conclusions: Our findings suggest that examining the effect of thyroid cancer diagnosis, cancer treatment, and demographic characteristics on the risk of CVD is critical.

An analysis of factors predicting lateral cervical nodal metastases in papillary carcinoma of the thyroid.

OBJECTIVE: To analyze the possible correlation between the location of the primary tumor within the thyroid gland and the patterns of central vs lateral compartment lymph node metastasis. DESIGN: Retrospective analysis of papillary thyroid carcinoma (PTC) treated in an academic university setting from July 1, 2004, through August 31, 2010. SETTING: Head and neck oncology clinic. PATIENTS: Those receiving surgical therapy for PTC at the University of Utah. MAIN OUTCOME MEASURES: Tumor characteristics of patients with central vs lateral nodal metastatic disease in PTC. RESULTS: Two hundred one patients with PTC met inclusion criteria. There were 136 females (67.7%), and the mean age was 44.8 years. Histologic subtypes included 68 follicular variants of PTC, 111 conventional variants of PTC, and 22 patients with both follicular and conventional PTC variants. Metastatic nodal disease was confirmed histologically in 81 patients (40.3%): 42 with central nodal disease only (20.9%), 10 with lateral disease only (5.0%), and 29 with both central and lateral nodal disease (14.4%). Positive lateral compartment nodal metastasis correlated with distant metastases (P < .01), extrathyroid extension (P < .05), histologic subtype (conventional PTC greater than follicular variant PTC) (P < .05), and tumor location within the thyroid lobe (P < .01). Tumors involving the superior aspect of the thyroid lobe were more likely to be associated with metastasis to the lateral cervical lymph nodes (P < .01), and 76.9% of patients with lateral cervical lymph node disease had involvement of the superior aspect of the lobe. Thyroid microcarcinomas were not associated with lateral cervical compartments in this study. CONCLUSIONS: The intrathyroidal location of PTC predicts the pattern of nodal spread. Therefore, patients with PTC involving the superior aspect of the lobe should undergo specific imaging evaluation of the lateral neck compartments to determine the need for lateral compartment neck dissection.

Parathyroid fine-needle aspiration cytology in the evaluation of parathyroid adenoma: cytologic findings from 53 patients.

This study was designed to assess the utility of fine-needle aspiration cytology (FNAC) in the preoperative localization of parathyroid adenoma (PA). Fifty-seven samples from fifty-three cases of PA (four patients had bilateral disease) were obtained by ultrasound (US)-guided fine-needle aspiration. Parathyroid hormone (PTH) estimation was performed on the supernatant of the aspirated fluid on all cases. Subsequently, all of them underwent cytologic evaluation. The cytology slides were evaluated using the following criteria: Cellularity, architectural patterns, bare nuclei in the background, nuclear morphology, and background features (colloid-like material or macrophages). Parathyroid cells were seen in 23 samples (40.4%). The cellularity of the smears was insufficient for interpretation in 16 samples (28.1%); and thyroid follicles and colloid were seen in 18 samples (31.5%). Majority of the samples with parathyroid cells showed moderate cellularity with monomorphous round to slightly oval cells predominantly arranged in loose two-dimensional clusters with occasional papillary fragments. Majority of them exhibited a stippled nuclear chromatin. No significant pleomorphism, mitotic activity, or prominent nucleoli were observed. Most samples showed bare nuclei in the background. In conclusion, US-guided FNAC has its limitations because of low sensitivity in primary localization of the parathyroid adenoma in cases of primary hyperparathyroidism and is not a useful mode of investigation in cases of PA.