Well-differentiated Thyroid Cancer Research Articles

Determining an Approach to Discharge from Oncologic Follow-up in Low-Risk, Well-Differentiated Thyroid Cancer with Excellent Response To Initial Therapy

Determining an Approach to Discharge from Oncologic Follow-up in Low-Risk, Well-Differentiated Thyroid Cancer with Excellent Response To Initial Therapy

New strategy for intraoperative phonosurgical management of recurrent laryngeal nerve infiltrated by thyroid carcinoma

PurposeTreating an infiltration of the recurrent laryngeal nerve (RLN) by thyroid carcinoma remains a subject of ongoing debate. Therefore, this study aims to provide a novel strategy for intraoperative phenosurgical management of RLN infiltrated by thyroid carcinoma.MethodsForty-two patients with thyroid carcinoma infiltrating the RLN were recruited for this study and divided into three groups. Group A comprised six individuals with medullary thyroid cancer who underwent RLN resection and arytenoid adduction. Group B consisted of 29 differentiated thyroid cancer (DTC)patients who underwent RLN resection and ansa cervicalis (ACN)-to-RLN anastomosis. Group C included seven patients whose RLN was preserved.ResultsThe videostroboscopic analysis and voice assessment collectively indicated substantial improvements in voice quality for patients in Groups A and B one year post-surgery. Additionally, the shaving technique maintained a normal or near-normal voice in Group C one year post-surgery.ConclusionThe new intraoperative phonosurgical strategy is as follows: Resection of the affected RLN and arytenoid adduction is required in cases of medullary or anaplastic carcinoma, regardless of preoperative RLN function. Suppose RLN is found infiltrated by well-differentiated thyroid cancer (WDTC) during surgery, and the RLN is preoperatively paralyzed, we recommend performing resection the involved RLN and ACN-to-RLN anastomosis immediately during surgery. If vocal folds exhibit normal mobility preoperatively, the MACIS scoring system is used to assess patient risk stratification. When the MACIS score > 6.99, resection of the involved RLN and immediate ACN-to-RLN anastomosis were performed. RLN preservation was limited to patients with MACIS scores ≤ 6.99.

Diagnostic Accuracy of Ultrasound and Fine-Needle Aspiration Cytology in Thyroid Malignancy.

Introduction: Thyroid nodule incidence is increasing due to the widespread application of ultrasonography. Fine-needle aspiration cytology is widely applied for the detection of malignancies. The aim of this study was to evaluate the predictive value of ultrasonography in thyroid cancer. Methods: This retrospective study included patients that underwent total thyroidectomy for benign thyroid disease or well-differentiated thyroid carcinoma from January 2017 to December 2022. The study population was divided into groups: the well-differentiated thyroid cancer group and the control group with benign histopathological reports. Results: In total, 192 patients were enrolled in our study; 159 patients were included in the well-differentiated thyroid cancer group and 33 patients in the control group. Statistical analysis demonstrated that ultrasonographic findings such as microcalcifications (90.4%), hypoechogenicity (89.3%), irregular margins (92.2%) and taller-than-wide shape (90.5%) were correlated to malignancy (p < 0.001). Uni- and multivariate analysis revealed that both US score (OR: 2.177; p < 0.001) and Bethesda System (OR: 1.875; p = 0.002) could predict malignancies. In terms of diagnostic accuracy, the US score displayed higher sensitivity (64.2% vs. 33.3%) and better negative predictive value (34.5% vs. 24.4%) than the Bethesda score, while both scoring systems displayed comparable specificities (90.9% vs. 100%) and positive predictive values (97.1% vs. 100%). Discussion: The malignant potential of thyroid nodules is a crucial subject, leading the decision for surgery. Ultrasonography and fine-needle aspiration cytology are pivotal examinations in the diagnostic process, with ultrasonography demonstrating better negative predictive value.

Implementation of the 2015 American Thyroid Association guideline changes across a health system: A quality improvement opportunity

BackgroundWith the release of the 2015 management guidelines, the American Thyroid Association narrowed the indications for postoperative radioactive iodine (RAI) in well-differentiated thyroid cancer. However, the adoption of new guidelines varies between healthcare entities. The goal of this study was to characterize the appropriateness of RAI use within our health system, before and after the 2015 guideline changes. MethodsIn this retrospective cohort study, we identified patients who were treated for well-differentiated thyroid cancer between 2011–2020. Patients were characterized as “undertreated,” “appropriately treated,” or “overtreated” with RAI. Variation in RAI use was assessed using interrupted time series and multivariable logistic regression analyses. ResultsAmong 6310 patients, the mean age was 50 ± 15 years, and 74% were female. There was an immediate drop in the likelihood of receiving RAI after the release of the 2015 guidelines (p = 0.016), and the likelihood of receiving RAI therapy continued to significantly decline over time (OR 0.83, p < 0.001). Despite this trend in the absolute rate of RAI use, there was a significant increase in overtreatment with RAI after the release of the 2015 guidelines (p < 0.001), indicating imperfect uptake of the new criteria. Two hospitals within the health system were identified as disproportionate contributors to overtreatment (Hospital 4: OR 6.50, p < 0.001; Hospital 6: OR 8.63, p < 0.001). ConclusionsWhile the use of postoperative RAI was largely appropriate across our health system, rates of guideline adherence differed between hospitals. Efforts to standardize treatment protocols systemwide may enable more rapid and consistent uptake of new management guidelines.

The Effect of I-131 Treatment on Complete Blood Count

Radioactive iodine-131 (RAI) treatment may cause suppression in the bone marrow. In this study, hemoglobin levels, leukocyte, thrombocyte, and lymphocyte counts will be compared before total thyroidectomy and 6 months after RAI treatment. 97 patients (76 females, 21 males) with a diagnosis of well-differentiated thyroid cancer who had undergone total thyroidectomy and received 50-200 mCi RAI treatment were included in the study. Hemoglobin levels, leukocyte, thrombocyte, and lymphocyte counts of the patients in the last month before the treatment and in the sixth month after the treatment were compared retrospectively. When the whole patients were analyzed, hemoglobin levels, leukocyte, thrombocyte, and lymphocyte counts in pretreatment were statistically lower than after-treatment values. While hemoglobin levels of female patients were similar before and after treatment, lymphocyte, thrombocyte, and leukocyte counts were statistically lower before treatment. Hemoglobin levels, leukocyte,and thrombocyte counts were similar before and after treatment, while lymphocytes decreased significantly after RAI treatment. Thyroid cancer patients who received 50-200 mCi RAI treatment after total thyroidectomy, have bone marrow suppression but are still in normal mean value ranges. This mild bone marrow suppression is more prominent in female patients than in male patients.

ALK-mutated thyroid cancer

At the moment, the standard of treatment in the Russian Federation for late stages of well-differentiated thyroid cancer (hereinafter referred to as WDTC) with a recorded radioiodine-resistant tumor status is the sequential administration of multikinase inhibitors: Sorafenib, Lenvatinib. Treatment protocols for subsequent lines have not been developed. The purpose of this article is to review the main molecular genetic features of WDTC and present the clinical observation of a patient with metastatic radioiodine-resistant follicular varient of papillary thyroid cancer (hereinafter referred to as PTC), which has progressed after previous lines of therapy. The patient’s tumor biological material was submitted for next-generation sequencing (NGS), which allows detection of all classes of molecular changes for a large number of genes. Due to the discovery of an ALK mutation and the lack of registered standards for subsequent treatment, ALK inhibitors were prescribed. This attempt to individualize therapy was successful: a partial response was registered during therapy and a significant clinical improvement in the patient’s general condition was noted. Therapy with ALK inhibitors continues to this day (46 months as of October 2023) and has a favorable toxicity profile. Thus, we can conclude that when the basic standards for the treatment of metastatic well-differentiated thyroid cancer have been exhausted, there is an individual selection of targeted therapy depending on the molecular genetic characteristics of the tumor process.

Abstract 1253: Pan-cancer comparative and integrative analyses of driver alterations using Japanese and international genomic databases

Abstract Recent large-scale pan-cancer genome projects have broadened our understanding of the cancer genome. However, these projects mainly consisted of White patients, with a limited focus on Asian populations. In addition, while pairwise relationships between driver alterations can provide valuable functional insights, the majority of these analyses are limited to those using The Cancer Genome Atlas (TCGA) dataset. Here we present a pan-cancer landscape of driver alterations in Japanese patients with advanced solid tumors using targeted sequencing data of 48,627 samples from the Center for Cancer Genomics and Advanced Therapeutics (C-CAT) in Japan. This data set had a greater number of samples from Asian-prevalent cancer types, such as intrahepatic cholangiocarcinoma and stomach adenocarcinoma, compared to the Genomics Evidence Neoplasia Information Exchange (GENIE) cohort. In the C-CAT cohort, the most frequently mutated gene was TP53 (56%), followed by KRAS (25%), APC (17%), and PIK3CA (12%). Gene fusions were detected in 1,166 samples (2%), including ERG fusions in prostate adenocarcinoma (n = 129), and RET and ALK fusions in lung adenocarcinoma (n = 30 and 32). At least one clinically actionable genetic lesion was found in 16% of patients, with well-differentiated thyroid cancer having the highest proportion. A comparative analysis of somatic mutation frequencies was conducted between the C-CAT cohort and the White population in the GENIE cohort. Among 352 driver gene-cancer type combinations, 14 and 4 were significantly higher and lower in the C-CAT cohort (&amp;gt; 10% difference with q-value &amp;lt; 0.01). Notably, TP53 mutation frequencies were elevated in the C-CAT cohort across 10 cancer types, suggesting racial differences in TP53 mutation frequencies. We then integrated C-CAT, GENIE, and TCGA data consisting of more than 150,000 patients to conduct a meta-analysis of co-occurring and mutually exclusive relationships between 1,790 cancer-driver combinations. This analysis not only validated 215 previously reported relationships but identified 484 novel ones. Interestingly, we found significantly co-occurring mutations within the epigenetic pathway, with 13 epigenetic regulators co-occurring in ten cancer types. Gene set enrichment analysis using RNA-sequencing data in TCGA revealed that accumulation of mutations in epigenetic regulators causes increased proliferation-related transcriptomic signatures. In addition, loss-of-function mutations in epigenetic drivers suppresses proliferation in wild-type cell lines, but this effect is reduced in cells with mutations in both the same and other epigenetic drivers. Our multi-cohort analyses uncover differences in the driver landscape between Asian and White populations, provides valuable resources for precision cancer medicine, and offers insights into epigenetic regulator-associated oncogenesis. Citation Format: Sara Horie, Yuki Saito, Yasunori Kogure, Kota Mizuno, Yuta Ito, Mariko Tabata, Koichi Murakami, Junji Koya, Keisuke Kataoka. Pan-cancer comparative and integrative analyses of driver alterations using Japanese and international genomic databases [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 1253.

Validating the Modified McGill Thyroid Nodule Score for Assessment of Preoperative Risk of Pediatric Thyroid Malignancy

ObjectiveThe McGill Thyroid Nodule Score (MTNS) is a preoperative tool used to predict the risk for well-differentiated thyroid cancer in adults. It was developed by a multidisciplinary team using established evidence-based risk factors for thyroid cancer. The modified McGill Thyroid Nodule Score (mMTNS) was developed to predict malignancy risk in children. A pilot study suggested the mMTNS was able to assess malignancy risk in children with indeterminate cytology on fine needle aspiration (FNA). This study seeks to validate these findings. MethodsRetrospective chart review identified subjects who underwent FNA biopsy and subsequent resection. Each patient was assigned a score to compare to final pathology. Statistical analysis was performed with SPSS. All tests were 2-tailed and statistical significance defined p < 0.05. Logistic regression used to determine predictive values of scores. Results46 patients ≤21 years of age underwent resection of a thyroid nodule. Female predominance of 85% (n = 39). 78% (n = 36) of patients had palpable nodule. 65% (n = 30) found to have benign pathology and 35% (n = 16) found to have malignancy. Malignant nodules associated with greater mean mMTNS compared to benign [13.63 vs 7.23]. An mMTNS greater >12 had sensitivity of 86.7%, specificity of 90.3%, positive predictive value of 81.3%, and negative predictive value of 93.3%. ConclusionOur data suggests the mMTNS continues to be a useful adjunct in predicting malignancy risk of pediatric thyroid nodules. An mMTNS >12 has a high risk for malignancy, which can aid in counseling and clinical decision making, particularly when there is indeterminate cytology on FNA. Level of EvidenceIV.

Is the nodule location a predictive risk factor for cancer in AUS/FLUS thyroid nodules? A retrospective cohort study

Atypia of undetermined significance/follicular lesion of undetermined significance (AUS/FLUS) is a heterogeneous category of thyroid nodules with uncertain cytology and controversial management. This study aimed to assess the association between nodule location and malignancy risk and whether the location can be used as a predictive risk factor for cancer in AUS/FLUS nodules. A cohort of 102 patients (79 [77.5%] women, 23 [22.5%] men) was retrospectively analyzed. Only patients with a final histopathology of benign or well-differentiated thyroid cancer and an available nodule location were included. Sociodemographic, histopathological, and sonographic data were statistically evaluated and correlated. Based on pathology findings, 54 (52.9%) and 48 (47.1%) nodules were benign and malignant, respectively. Most nodules were right-sided (54.9%). Considering the nodule location, 41.2% of nodules occupied the whole lobe, 20.6% only the lower pole, 15.7% only the upper pole, and 2.9% the isthmus. Cases with nodules occupying only the upper, middle, or lower pole showed significant associations with cancer risk (odds ratio, [95% confidence interval]: 2.6, [1.1-5.7]; 2.0, [1.0-4.7]; and 1.9, [1.0-3.9], respectively). Male sex and the presence of a peripheral halo were significantly associated with malignancy risk (3.3, [1.2-9.1], P=0.014; and 2.7, [1.0-9.5], P=0.049, respectively). Isthmic nodules had the highest malignancy level (66.7%). Nodule location is a promising predictor of malignancy in AUS/FLUS nodules. Furthermore, isthmic nodules had the highest malignancy level, emphasizing the significance of careful evaluation of these nodules. Further large prospective studies are required to confirm these findings.

Quality of Life in Patients With Well-Differentiated Thyroid Carcinoma After Total Thyroidectomy in Greece.

Well-differentiated thyroid cancer is among the most common types of endocrine cancer. Despite its increasing prevalence, the prognosis of thyroid cancer is rather good, with a five-year survival rate ranging between 80% and 90%, depending on the histological type. Not only the post-treatment complications and the side effects of the lifelong medicationbut also the possibility of a recurrence may have a negative impact on the patient's quality of life (QoL). The aim of this study is to investigate the impact of total thyroidectomy on the QoL of patients with well-differentiated thyroid carcinoma. A prospective study was performed in patients who underwent total thyroidectomy due to well-differentiated thyroid carcinoma in the Otolaryngology-Head and Neck Surgery Department at the University Hospital of Larissa, Greece. The QoL was evaluated based on the "Quality of Life (Thyroid Version)" questionnaire. One hundred patients participated in the study, with a mean age of 51.24±15.33 years. Of these, 63 (63%) were females and 37 (37%) were males. Social concerns, physical well-being, and psychological well-being presented a gradual positive alteration during the first 12 months after the surgery, with psychological well-being reporting the most significant progress of 15.3%. However, spiritual well-being appeared to decline over time. The younger patients progressively improved their physical, psychological, and mental well-being; however, the older patients showed an amelioration of their social skills. Female patients reported higher levels of spiritual well-being, whereas males developed better social skills. In the long term, total thyroidectomy can ameliorate patients' physical status, psychological well-being, and social concerns. However, it might have a negative effect on their mental health during the first 12 months postoperatively. In addition, QoL is directly influenced by demographic characteristics such as age and gender.

Chapter 5: Surgery for Neck in Well-differentiated Thyroid Cancers

ABSTRACT Thyroid cancers frequently metastasize to neck nodes. However, most of these are occult micrometastases with no impact on survival, while only a small percentage have clinically apparent neck nodes. The impact of nodal metastases on overall survival is very low, as compared to other head-neck sites and pathologies. Hence the surgical management of neck nodes has to be balanced with the likely morbidity of these procedures. This narrative review deals with the management of neck nodal metastasis of well differentiated thyroid cancers.

Unusual mesentery metastasis of differentiated thyroid cancer: a case report.

Distant metastases of well-differentiated thyroid cancers (WDTCs) to bone and lungs are well known, while intra-abdominal, mesenteric metastases are very rare. Herein, we report a case of intra-abdominal, mesenteric metastasis of WDTC. A 62-year-old man underwent thyroid lobectomy for follicular thyroid cancer. One year later, lung metastasis was observed. The patient simultaneously underwent lung wedge resection and complete thyroidectomy. Eleven years later, serum thyroglobulin level was elevated. On the work-up study, a metastatic lesion in the lungs and a mass in the mesentery were identified. Two lesions of the lung and mesentery were surgically resected. The mass in the mesentery was pathologically diagnosed as metastatic WDTC.

Genetic Analysis of Locally Advanced Well-Differentiated Thyroid Cancer: Clinical Prognostic Implications

Background and Objectives Despite the usually favorable prognosis of well-differentiated thyroid cancer (WDTC) following appropriate treatment, advanced T-staged WDTCs are associated with poor prognosis. This study focused on identifying genes associated with the prognosis of locally advanced WDTC by analyzing a The Cancer Genome Atlas cohort.Subjects and Method We analyzed the data of 501 patients with WDTC and classified them into two subgroups: pathological T4 stage (Cluster 1) or T1-3 stage (Cluster 2). We compared the mRNA expressions of thyroid cancer-related genes, and the somatic mutation frequencies of various cancer genes between the two subgroups.Results Cluster 1 included 23 patients (papillary=21/follicular-variant papillary thyroid cancer [FVPTC]=2) and Cluster 2 478 patients (papillary=371/FVPTC=100/others=7). Cluster 1 showed worse overall and disease-free survival than Cluster 2 (&lt;i&gt;p&lt;/i&gt;&lt;0.05 and &lt;i&gt;p&lt;/i&gt;=0.12, respectively). Patients with pT4 stage had about a 1.8-fold increased risk of overall recurrence or death. &lt;i&gt;MET, SERPINA1, TIMP1, PROS1, FN1, CDKN2A&lt;/i&gt;, and &lt;i&gt;CDKN2B&lt;/i&gt; were significantly elevated while &lt;i&gt;TG, DNAH9, TFF3, CRABP1, TPO, JAK2, KIT, KDR&lt;/i&gt;, and &lt;i&gt;NFE2L2&lt;/i&gt; were significantly lower in Cluster 1 (all, &lt;i&gt;p&lt;/i&gt;&lt;0.05 and adjusted &lt;i&gt;p&lt;/i&gt;&lt;0.05). A &lt;i&gt;TERT, EIF1AX&lt;/i&gt;, and &lt;i&gt;ATM&lt;/i&gt; showed significantly frequent somatic mutations in Cluster 1 when compared to Cluster 2. We also identified seven pathways related to 16 genetic markers.Conclusion Locally advanced WDTC presented 16 genetic alterations. We identified somatic mutations associated with local invasion transformation. Relevant pathways related to the 16 genetic markers could be therapeutic targets. Genetic analysis of locally advanced WDTC may be used to predict clinical applications in patient survival.

Dynamic changes of serum miR-105-3p expression and prognostic value evaluation of postoperative thyroid cancer.

To explore the dynamic changes of serum miR-105-3p expression after thyroid cancer surgery and its correlation with clinicopathological manifestations and to evaluate its clinical value as a potential biomarker after surgery. A total of 100 thyroid cancer patients admitted to Shaanxi Provincial People's Hospital from November 2020 to August 2021 were selected as the research objects. The aim was to detect the expression of serum miR-105-3p in patients and its correlation with tumor pathological characteristics (pathological type, tumor differentiation, TNM stage, lymph node metastasis), and to detect the dynamic changes of postoperative serum miR-105-3p in patients to evaluate its prognostic value as a potential biomarker. The level of serum miR-105-3p increases in patients with well-differentiated thyroid cancer and lymph node metastasis; the level of serum miR-105-3p gradually decreases with the passage of time after surgery, and there is a significant difference between 4 d after surgery and before surgery; serum miR-105-3p level can significantly distinguish between patients with poor prognosis and good prognosis within 2 years after the operation, and it can predict the improvement of the prognosis of thyroid cancer after surgery. The level of serum miR-105-3p is closely related to the degree of differentiation and lymph node metastasis in patients with thyroid cancer. Its level gradually decreases with the passage of time after surgery. It has a good diagnostic value for the prognosis of thyroid cancer after surgery and when it is expected to become a thyroid cancer surgery. Potential biomarkers for post-diagnosis.

Dynamic changes of serum miR-105-3p expression and prognostic value evaluation of postoperative thyroid cancer

Objective. To explore the dynamic changes of serum miR-105-3p expression after thyroid cancer surgery and its correlation with clinicopathological manifestations and to evaluate its clinical value as a potential biomarker after surgery. Methods. A total of 100 thyroid cancer patients admitted to Shaanxi Provincial People’s Hospital from November 2020 to August 2021 were selected as the research objects. The aim was to detect the expression of serum miR-105-3p in patients and its correlation with tumor pathological characteristics (pathological type, tumor differentiation, TNM stage, lymph node metastasis), and to detect the dynamic changes of postoperative serum miR-105-3p in patients to evaluate its prognostic value as a potential biomarker. Results. The level of serum miR-105-3p increases in patients with well-differentiated thyroid cancer and lymph node metastasis; the level of serum miR-105-3p gradually decreases with the passage of time after surgery, and there is a significant difference between 4 d after surgery and before surgery; serum miR-105-3p level can significantly distinguish between patients with poor prognosis and good prognosis within 2 years after the operation, and it can predict the improvement of the prognosis of thyroid cancer after surgery. Conclusions. The level of serum miR-105-3p is closely related to the degree of differentiation and lymph node metastasis in patients with thyroid cancer. Its level gradually decreases with the passage of time after surgery. It has a good diagnostic value for the prognosis of thyroid cancer after surgery and when it is expected to become a thyroid cancer surgery. Potential biomarkers for post-diagnosis.

Machine Learning Model as a Useful Tool for Prediction of Thyroid Nodules Histology, Aggressiveness and Treatment-Related Complications.

Thyroid nodules are very common, 5-15% of which are malignant. Despite the low mortality rate of well-differentiated thyroid cancer, some variants may behave aggressively, making nodule differentiation mandatory. Ultrasound and fine-needle aspiration biopsy are simple, safe, cost-effective and accurate diagnostic tools, but have some potential limits. Recently, machine learning (ML) approaches have been successfully applied to healthcare datasets to predict the outcomes of surgical procedures. The aim of this work is the application of ML to predict tumor histology (HIS), aggressiveness and post-surgical complications in thyroid patients. This retrospective study was conducted at the ENT Division of Eastern Piedmont University, Novara (Italy), and reported data about 1218 patients who underwent surgery between January 2006 and December 2018. For each patient, general information, HIS and outcomes are reported. For each prediction task, we trained ML models on pre-surgery features alone as well as on both pre- and post-surgery data. The ML pipeline included data cleaning, oversampling to deal with unbalanced datasets and exploration of hyper-parameter space for random forest models, testing their stability and ranking feature importance. The main results are (i) the construction of a rich, hand-curated, open dataset including pre- and post-surgery features (ii) the development of accurate yet explainable ML models. Results highlight pre-screening as the most important feature to predict HIS and aggressiveness, and that, in our population, having an out-of-range (Low) fT3 dosage at pre-operative examination is strongly associated with a higher aggressiveness of the disease. Our work shows how ML models can find patterns in thyroid patient data and could support clinicians to refine diagnostic tools and improve their accuracy.

Partial Thyroidectomy With Incidental Metastatic Lymph Nodes

The need for completion thyroidectomy in patients with incidental metastatic lymph nodes after partial thyroidectomy is unclear. To investigate the outcomes of patients with incidental metastatic lymph nodes following partial thyroidectomy. A retrospective review of a prospectively maintained thyroid cancer database from 1985 to 2015 was carried out at a head and neck surgery practice at a tertiary referral cancer center. A total of 74 patients who underwent thyroid lobectomy or thyroid isthmusectomy between 1985 and 2015 and were found to have incidental metastatic lymph nodes on final pathologic analysis and were selected to be observed without immediate completion thyroidectomy were included. A separate group of additional 11 patients who underwent immediate completion thyroidectomy was also identified and reviewed. Analysis took place from February to May 2022. Recurrence-free survival outcomes of patients found to have incidental metastatic lymph nodes on final pathologic analysis following partial thyroidectomy with no immediate completion thyroidectomy. A total of 74 patients were observed, with a median (IQR) age of 39 (28-49) years; 44 (59%) were women. Sixty-four patients underwent thyroid lobectomy and 10 patients had isthmusectomy. Classic papillary thyroid carcinoma was the most common histologic type (34 [46%]). Vascular invasion and microscopic extrathyroidal extension were present in 11 patients (16%) and 22 patients (30%), respectively. Positive margins were identified in 5 patients (7.8%). Size of metastatic lymph nodes ranged between 0.07 cm and 1.2 cm. No extranodal extension was reported. A total of 52 patients (70%) were classified as intermediate risk for recurrence based on the American Thyroid Association risk stratification system. The median (IQR) follow up was 48.15 (15.4-86.1) months, during which only 1 patient had a regional recurrence. Another patient underwent delayed completion thyroidectomy for a contralateral lobe malignant abnormality. Recurrence-free survival, disease-specific survival, and overall survival were 97.4%, 100%, and 96.2%, respectively. A separate group of 11 patients who underwent immediate completion thyroidectomy were reviewed. These patients were more likely to have tall-cell papillary thyroid carcinoma (6 [55%] vs 13 [18%]), multifocality (9 [82%] vs 28 [41%]), microscopic extrathyroidal extension (8 [73%] vs 22 [30%]), and positive margins (3 [30%] vs 5 [7.8%]) compared with patients who were under observation only. Completion thyroidectomy may not be necessary in appropriately selected patients who are found to have incidental metastatic lymph nodes (N1a) after partial thyroidectomy for localized well-differentiated thyroid cancer.

Role of computed tomography in the evaluation of regional metastasis in well-differentiated thyroid cancer.

Accurate neck staging is essential for performing appropriate surgery and avoiding undue morbidity in thyroid cancer. The modality of choice for evaluation is ultrasonography (US), which has limitations, particularly in the central compartment, that can be overcome by adding a computed tomography (CT). A total of 314 nodal levels were analyzed in 43 patients with CT, and US; evaluations were done between January 2013 and November 2015. The images were reviewed by two radiologists independently who were blinded to histopathological outcomes. The sensitivity, specificity, negative predictive value (NPV), positive predictive value (PPV), and accuracy of US, CT, and US + CT were calculated using histology as the gold standard. The overall sensitivity, specificity, PPV, and NPV for US, CT, and US + CT were 53.9%, 88.8%, 74.1%, and 76.4%; 81.2%, 68.0%, 60.1%, and 85.9%; and 84.6%, 66.0%, 59.6%, and 87.8%, respectively. The overall accuracy of the US was 75.80%, the CT scan was 72.93%, and the US + CT scan was 72.93%. For the lateral compartment, the sensitivity, specificity, PPV, and NPV for the US, CT, and US + CT were 56.6%, 91.4%, 77.1%, and 80.5%; 80.7%, 70.6%, 58.3%, and 87.8%; and 84.3%, 68.7%, 57.9%, and 89.6%, respectively. The accuracy of the US was 79.67%, the CT scan was 73.98%, and the US + CT scan was 73.98% for the lateral compartment. For the central compartment, the sensitivity, specificity, PPV, and NPV for the US, CT, and US + CT were 47.1%, 76.5%, 66.7%, and 59.1%; 82.4%, 55.9%, 65.1%, and 76.0%; and 85.3%, 52.9%, 64.4%, and 78.3%, respectively. The accuracy of the US was 61.76%, the CT scan was 69.12%, and the US + CT scan was 69.12% for the central compartment. This study demonstrated that CT has higher sensitivity in detecting nodal metastasis; however, its role is complementary to US due to low specificity.

SAT576 Change Is Not Always For The Best! A Transformation of Papillary Into Metastatic Anaplastic Thyroid Carcinoma

Abstract Disclosure: J. Syeda: None. R. Zafar: None. K. Rajamani: None. INTRODUCTION: Anaplastic thyroid carcinoma (ATC) can occur de-novo or from preexisting well-differentiated thyroid carcinoma (1). The presence or absence of certain driver mutations can help predict the likelihood of this transformation process. We present a case of an elderly female with an initial diagnosis of well-differentiated papillary thyroid cancer (PTC) with a transformation into metastatic anaplastic thyroid carcinoma (ATC). CASE PRESENTATION: An 81-year-old female patient was initially seen 8 years ago with a 35-year history of goiter. At the initial presentation, she felt well and did not have any symptoms. Physical examination revealed an enlarged thyroid gland with left lobe nodularity. A thyroid ultrasound showed a multinodular thyroid gland including a 2x1.7x1.2 cm solid nodule with macro calcifications in the right lobe, 2.8x2.6x2.5 cm solid nodule, and 1.6x1.3x1.6 cm heterogeneous solid nodule with calcifications and irregular margins in the left lobe. She had a fine needle aspiration of these three nodules. The right nodule was non-diagnostic and both left nodules were positive for PTC. She underwent a total thyroidectomy and central lymph node dissection. Radioactive iodine treatment with 163mCi was administered after surgery. One and a half years after surgery, her thyroglobulin levels started trending upward. This led to a further workup including a PET/CT scan, which showed a hyper metabolic 6 mm left supraclavicular lymph node. Needle biopsy of this lymph node disclosed metastatic PTC. The pathologic diagnosis following surgical resection was positive for metastatic poorly differentiated thyroid carcinoma. A subsequent PET/CT scan and a thyroid ultrasound showed an abnormal uptake of the left neck lymph node and additional metastatic nodes in the left neck respectively. A core needle biopsy of these lesions was positive for ATC. Foundation One CDx testing was positive for BRAF V600E, TP53, and TERT promoter mutations. Cellblock from the initial thyroidectomy was reevaluated by pathology and confirmed no evidence of ATC. Foundation One CDx testing of the thyroidectomy specimen was positive for BRAF V600E and TERT promoter mutations. Surveillance imaging shows mediastinal adenopathy, left pleural thickening, and bone and liver metastases. DISCUSSION: Anaplastic transformation is not uncommon (1). This case supports the evidence that TERT promoter mutations may not trigger anaplastic transformation but may predispose to the aggressive PTC phenotype prone to conversion to ATC when one of the ATC-related “second hit” genetic events occurs (2). This case suggests that the “second hit” event is a TP53 mutation. The detection of a TP53 mutation in PTC with an aggressive phenotype may help predict anaplastic transformation. REFERENCES: 1-Endocrine Pathology. 2021 Mar; 32(3):347-356. 2- Semin Cancer Biol. 2020 Apr; 61: 23-29. Presentation: Saturday, June 17, 2023

2214P Identification of prognosis-associated genes in locally advanced well-differentiated thyroid cancer using TCGA cohort analysis

2214P Identification of prognosis-associated genes in locally advanced well-differentiated thyroid cancer using TCGA cohort analysis