Faculty Bibliography

CONTEXT/BACKGROUND:Comprehensive genomic analysis of thyroid nodules for multiple classes of molecular alterations detected in a large series of fine-needle aspiration (FNA) samples has not been reported. OBJECTIVE:To determine the prevalence of clinically relevant molecular alterations in Bethesda categories III-VI (BCIII-VI) thyroid nodules. DESIGN/METHODS:Retrospective analysis of FNA samples tested by ThyroSeq v3 using Genomic Classifier and Cancer Risk Classifier. SETTING/METHODS:UPMC MGP laboratory. PARTICIPANTS/METHODS:A total of 50,734 BCIII-VI nodules from 48,225 patients. INTERVENTION/METHODS:None. MAIN OUTCOME MEASURES/METHODS:Prevalence of diagnostic, prognostic, and targetable genetic alterations. RESULTS:Among 50,734 informative FNA samples, 65.3% were test-negative, 33.9% positive, 0.2% positive for medullary carcinoma, and 0.6% positive for parathyroid. The benign call rate in BCIII-IV nodules was 68%. Among test-positive samples, 73.3% had mutations, 11.3% gene fusions, and 10.8% isolated copy number alteration. Comparing BCIII-IV nodules with BCV-VI nodules revealed a shift from predominantly RAS-like alterations to BRAF V600E-like alterations and fusions involving receptor tyrosine kinases (RTK). Using ThyroSeq Cancer Risk Classifier, a high-risk profile, which typically included TERT or TP53 mutations, was found in 6% of samples, more frequently BCV-VI. RNA-Seq confirmed ThyroSeq detection of novel RTK fusions in 98.2% of cases. CONCLUSIONS:In this series, 68% of BCIII-IV nodules were classified as negative by ThyroSeq, potentially preventing diagnostic surgery in this subset of patients. Specific genetic alterations were detected in most BCV-VI nodules, with a higher prevalence of BRAF and TERT mutationsand targetable gene fusions compared to BCIII-IV nodules, offering prognostic and therapeutic information for patient management.

Image-guided interventional techniques have emerged as promising treatments for thyroid disease. Percutaneous ethanol ablation, radiofrequency ablation, laser ablation, high intensity focused ultrasound, and microwave ablation have shown efficacy in treating benign thyroid disease. There is increasing evidence that these techniques may effectively treat papillary thyroid microcarcinomas, recurrent and metastatic disease, follicular neoplasms, and parathyroid lesions. They are performed in an outpatient setting, well-tolerated, with negligible risk for thyroid hormone supplementation, making them a popular alternative to surgical resection. In this comprehensive review, we discuss the devices, techniques, advantages, and disadvantages of each intervention, and summarize the published outcomes.

Introduction: The prognostic significance of a singular RAS mutation in cytologically indeterminate thyroid nodules (ITN) is unclear. This study aimed to analyze the incidence of malignancy and clinical outcomes of ITNs diagnosed on fine needle aspiration (FNA) cytology with RAS mutations.
Method(s): All FNA ITNs that underwent ThyroSeq testing and thyroidectomy from 2014-2018 were reviewed. ITNs with RAS (N-, H-, or K-RAS) mutations identified on ThyroSeq testing were selected. Demographics, Bethesda classifications, genomic profiles, treatment, final pathology, and clinical outcomes were recorded.
Result(s): During the study period, 93 patients with cytologic diagnosis of ITN and RAS mutations were identified. The mean nodule size was 2.2 cm (range: 0.5-6.6 cm). Most nodules were classified as Bethesda III (77, 82.8%). NRAS mutations were the most common (53, 57%), followed by HRAS (24, 25.8%), and KRAS (16, 17.2%). The majority of patients were treated with thyroid lobectomy (67, 72%). On final pathology, 9 (10%) were diagnosed as malignant (follicular variant of papillary thyroid carcinoma [FVPTC]) and were distributed among all 3 RAS variants (NRAS: 4 [7.5%]; HRAS: 4 [16.7%]; KRAS: 1 [6.3%]; p=0.4). Most FVPTCs were encapsulated (8, 88.9%). With a median follow up of 19 months (interquartile range = 8-35), no recurrences or progression was seen.
Conclusion(s): The risk of malignancy in ITNs with singular RAS mutations is low. All malignancies were low-risk. Our findings demonstrate a low incidence of high-risk malignancy in ITNs with RAS mutations, suggesting that initial management with conservative approaches such as thyroid lobectomy may be justified.
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Introduction: Molecular tests such as ThyroSeq are recommended in the workup of cytologically indeterminate thyroid nodules (ITN). While repeat molecular testing is often performed after repeat fine needle aspiration (FNA) yields persistently indeterminate cytology, ThyroSeq's inter-test reliability is unclear. We assessed consistency of initial and repeat ThyroSeq analyses performed on samples from the same thyroid nodules.
Method(s): All thyroid nodules diagnosed as ITN on consecutive FNAs that received ThyroSeq with both biopsies from 2014-2018 at our institution, were reviewed. Initial analysis was ThyroSeq v2 while repeat was v2 or v3. Nodules with gene mutations, fusions, or copy number alterations (CNA) were considered ThyroSeq-positive.
Result(s): During the study period, 30 patients underwent ThyroSeq analysis on initial and repeat FNA samples (median interval=21 months). On initial testing, 27 (90%) nodules were ThyroSeq-negative and 3 (10%) low-risk mutations (RAS, EIF1AX, TSHR) were identified. Repeat ThyroSeq re-identified these 3 nodules and also interpreted 9 initially ThyroSeq-negative nodules as positive (kappa=0.286). All 9 molecular alterations were low-risk, most were identified on v3 (7, 77.8%), and CNA was the most common change (6, 66.7%). Of 12 patients with ThyroSeq-positive nodules, 8 underwent lobectomy. Final pathology identified low-risk malignancy in 3 nodules; the remainder were benign.
Conclusion(s): New findings on repeat ThyroSeq are possible. Whether these findings were detected by expanded panel or are the result of de-novo changes is unknown. The risk of missing high-risk changes appears to be low. More studies are needed to characterize the concordance of ThyroSeq analyses and natural evolution of ITNs.
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BACKGROUND:Unlike medullary thyroid carcinoma in adults, the vast majority of pediatric medullary thyroid carcinoma is hereditary. Pediatric medullary thyroid carcinoma is known to have different genetic alterations driving tumorigenesis, but it is not known if pediatric medullary thyroid carcinoma has different clinicopathologic features. This study aims to identify which pediatric medullary thyroid carcinoma patients might warrant elective neck dissection. METHODS:We selected all patients ages 0 to 19 diagnosed with clinically evident medullary thyroid carcinoma in the National Cancer Database between 2004 to 2016. Clinicopathologic factors, treatments, and outcomes were analyzed and compared between this cohort and adults (ages ≥20) with medullary thyroid carcinoma. RESULTS:One hundred twenty-five pediatric medullary thyroid carcinoma (median age: 13) and 5,086 adult medullary thyroid carcinoma (median age: 57) patients were identified. Pediatric patients had smaller tumors (median diameter: 1.2 cm vs 2.0 cm; P < .001), lower rates of nodal metastases (n = 31, 36.9% vs 1,689, 50.4%; P = .02) but double the incidence of multifocal tumors (n = 70, 59.3%, vs 1,412, 29.9%; P < .001) compared with adults. Multifocal tumors conferred a significantly increased risk of nodal metastases in adult medullary thyroid carcinoma (64.4% vs 43.2%; P < .001) but not pediatric medullary thyroid carcinoma (37.7% vs 35.7%; P = .85). Nodal metastases were more frequent among older children (0-5 years: 0.0%, 6-12: 40.7%, 13-19: 41.7%; P = .04). However, rates of occult nodal metastases were similar between older children (6-19 years: n = 12, 21.4%) and adults (557, 25.8% P = .56). CONCLUSION/CONCLUSIONS:Pediatric medullary thyroid carcinoma has lower rates of lymph node metastases compared with adults. The risk of nodal disease was low among the youngest children, but older children ages 6 to 19 were at considerable risk for occult metastases. These findings could guide clinicians in selecting pediatric patients considered for elective lymph node dissection.

The majority of malignancies identified in indeterminate thyroid nodules (ITN) are low risk. Therefore, the need for total thyroidectomy or adjuvant treatment such as completion thyroidectomy or radioactive iodine (RAI) therapy in the treatment of ITNs is uncertain. This study aimed to analyze the likelihood of a need for total thyroidectomy and RAI therapy in the management of ITNs. All ITNs diagnosed on FNA cytology from 2014-2018 at NYU Langone Health were reviewed. ITNs managed with surgery were selected. Demographics, nodule characteristics, final pathology, treatment detail, and clinical outcomes were recorded. During the study period, 218 patients with surgically excised ITNs were identified. One hundred forty-two (65.1%) patients underwent thyroid lobectomy (TL), and 76 (34.9%) had total thyroidectomy (TT) upfront. In the lobectomy group, 26 (18.3%) had a malignant nodule on final surgical pathology, 8 (5.6%) underwent completion thyroidectomy, and 5 (3.5%) received RAI. In the total thyroidectomy group, 26 (34.2%) were diagnosed as malignant, and 14 (18.4%) received RAI. Follicular variant of papillary thyroid carcinoma (FVPTC) was the most common malignant diagnosis in both groups (TL: 20, 76.9%; TT: 12, 46.2%). Adenomatous nodule was the most common benign diagnosis (TL: 55, 72.5%; TT: 15, 51.2%). NIFTP accounted for 28.2% (40) of nodules treated with lobectomy and 27.6% (21) of nodules treated with upfront total thyroidectomy. In the entire cohort, only two (1%) patients had significant pathology in the contralateral lobe (1 [0.5%] with papillary thyroid carcinoma [PTC] and 1 [0.5%] with multifocal micro-PTC). Of all 218 ITNs, only 19 patients (8.7%) received RAI. With a median follow-up of 31.5 months (interquartile range = 21-39.5), no recurrences or progression was seen. The need for completion thyroidectomy or adjuvant RAI therapy in the treatment of ITN was low in our series. These data suggest that initial management of ITNs with lobectomy might be sufficient in the majority of cases

Context/UNASSIGNED:Thyroid hormone plays a critical role in cardiovascular function. Severe hypothyroidism can be associated with "myxedema heart" characterized by relative bradycardia and pericardial effusion. Effusions associated with severe hypothyroidism can be large. Despite the large volume of effusions, tamponade is not a common consequence. However, with the incorporation of echocardiography into routine practice for evaluation of effusion, echocardiographic findings suggestive of clinical tamponade occur frequently. Case Description/UNASSIGNED:We report a series of 3 patients with large pericardial effusions secondary to severe hypothyroidism. These cases serve to demonstrate the discordance between echocardiographic signs consistent with tamponade with a patient's stable clinical hemodynamics. We also report the development of bronchial obstruction, a rare complication of a large effusion due to severe hypothyroidism. Conclusions/UNASSIGNED:While pericardial effusion associated with severe hypothyroidism has been described for decades, the echocardiographic findings may be less well known and may lead to unnecessary downstream testing or invasive management. We use our case series to facilitate a summary of what is known about the epidemiology, mechanism and physiology, and expected outcomes of myxedema associated pericardial effusion. Finally, in the setting of current paucity of clinical guidelines, we aim to familiarize clinicians with the phenomenon of pseudotamponade and suggest management strategies for myxedema associated pericardial effusion to guide clinicians to use conservative medical management in majority of cases.

RATIONALE/BACKGROUND:Successful treatment of cocaine addiction is severely impeded by the propensity of users to relapse. Withdrawal severity may serve as a key predictor of susceptibility to relapse. Therefore, the identification and treatment of cocaine withdrawal symptoms such as anxiety may improve addiction treatment outcome. OBJECTIVES/OBJECTIVE:The current study examined the role of anxiety-like behavior during cocaine withdrawal and anxiolytic treatment in reinstatement of cocaine seeking in an animal model of relapse. METHODS:Male rats experienced daily IV cocaine self-administration. One group of animals received the norepinephrine α-2 agonist, guanfacine, or vehicle prior to anxiety testing 48 h after the last self-administration session. In the second group of rats, relationships between cocaine intake, anxiety-like behavior after withdrawal of cocaine, and reinstatement responding were investigated. The third and fourth groups of animals received guanfacine, yohimbine (norepinephrine α-2 antagonist), or vehicle once per day for 3 days 48 h after cessation of cocaine self-administration, followed by extinction and subsequent reinstatement induced by cocaine injections, cocaine-paired cues, and yohimbine administration. RESULTS:Cocaine-withdrawn rats at 48 h demonstrated higher levels of anxiety-like behavior as measured on a defensive burying task when compared to yoked saline controls, an effect reversed by guanfacine treatment. Cocaine intake was positively correlated with measures of anxiety-like behavior during early withdrawal, and this anxiety-like behavior was significantly correlated with subsequent cocaine-primed reinstatement. Yohimbine treatment during early withdrawal increased reinstatement to conditioned cues, while guanfacine treatment reduced reinstatement to yohimbine. CONCLUSIONS:These studies suggest an important role for noradrenergic mediation of anxiety-like behavior that emerges after withdrawal of cocaine and potential risk of relapse as modeled by reinstatement, and suggest that treatment of anxiety symptoms during early abstinence may reduce the risk of relapse.

Significant sex differences have been demonstrated in clinical and preclinical studies of cocaine addiction, with some of the most consistent differences noted in regard to the role of stress and craving. The current study examined stress-induced reinstatement of cocaine seeking in male and female rats in an animal model of relapse using corticotropin-releasing factor (CRF) administration. Both male and female rats demonstrated increased cocaine seeking in response to CRF. CRF-induced reinstatement was highly variable across both male and female rats, and further analysis revealed a subpopulation that was particularly sensitive to CRF (high responders). Female high responders displayed significantly increased responding to CRF compared to males. Individual differences in stress responsivity could thus contribute to the likelihood of relapse, with females showing greater heterogeneity to stress-induced relapse.