Medullary Thyroid Carcinoma Patients Research Articles

The pathological characteristics and prognostic analysis of medullary thyroid microcarcinoma

Objectives: To analyze the clinical characteristics and prognosis of medullary thyroid microcarcinoma (MTMC). Methods: A case series studies. The clinical data of patients with medullary thyroid carcinoma (MTC) diagnosed by postoperative pathology and with complete follow-up data who were initially treated in Tianjin Medical University Cancer Hospital from January 2013 to December 2019 were retrospectively analyzed. There were a total of 170 cases, including 70 males and 100 females, aged (49.7±12.3) years old. Among them, there were 61 patients with MTMC. They were divided into group A (with a maximum tumor idameter of ≤0.5 cm, n=13) and group B (with a maximum tumor diameter >0.5~≤1.0 cm, n=48) based on whether the maximum diameter of the tumor was >0.5 cm. Analysis was conducted on their pathological results and prognosis. Results: Among the MTC, MTMC accounted for 26.4% (61/231) with 26 males and 35 females aged M［Q1，Q3］51.0 (41.0, 59.0) years. Among the MTMC patients, 57.4% (35/61) were in stage Ⅰ, 16.4% (10/61) were in stage Ⅲ, and 26.2% (16/61) were in stage Ⅳ. For MTMC with a maximum diameter of≤0.5 cm and a maximum diameter of >0.5-≤1.0 cm, there was no statistically significant difference between the two groups in terms of gender, age, mixed cancer, invasion of glandular lobes, multifocal, central lymph node metastasis, lateral neck lymph node metastasis rate and other pathological characteristics(both P>0.05). In terms of prognosis, the recurrence free survival time of MTMC patients was 83.1 (68.0, 97.0) months. Among them, structural tumor recurrence occurred in 5 patients (8.2%) after surgery, and 1 patient (1.6%) died. The expected 5-year and 10-year survival rates were 93.4% and 89.0%, respectively. There was no statistically significant difference in recurrence free survival time among MTMC patients, MTC patients with a maximum diameter of >1.0-≤2.0 cm, and MTC patients with a maximum diameter of >2.0 cm (all P>0.05). Conclusion: MTMC has strong invasiveness, and although the prognosis of most MTMCs is relatively good, the risk of long-term recurrence and death is still high.

Neoadjuvant Treatment of Locally Advanced Thyroid Cancer: A Preliminary Latin American Experience.

Surgical resection is not always achievable in thyroid cancer patients. Neoadjuvant therapy is rarely used, but recent trends favor multikinase inhibitors or selective tyrosine kinase inhibitors. These aim to reduce tumor volume, enabling previously unfeasible surgeries. Consecutive patients with locally advanced malignant thyroid tumors who received systemic therapies with a neoadjuvant intention were included in this retrospective multicenter case series conducted in five Latin American referral centers. Primary outcomes were pre- versus post-neoadjuvant response evaluations using the Response Evaluation Criteria in Solid Tumors, feasibility of surgery and completeness of resection. Secundary outcomes were mortality and status at last visit. Twenty-seven patients were included in this analysis. Patients with unresectable differentiated thyroid cancer (DTC) or poorly differentiated thyroid cancer (PDTC) received sorafenib (n=6) or lenvatinib (n=12), those with medullary thyroid cancer (MTC) were treated with vandetanib (n=5) or selpercatinib (n=1), and those with anaplastic thyroid cancer (ATC) harboring a BRAF V600E mutation (n=3) received dabrafenib and trametinib. The median patient age was 66 years (range 12-82), and 52% of the patients were female. In patients with PTC and PDTC, the median reduction in the diameter of the primary tumor was 25% (range 0-100%) after a median of 6 months of treatment. Surgical intervention was performed in ten (55%) of the patients. Among these, six patients (60%) achieved R0/R1 resection status. Six patients with MTC had a median reduction in tumor diameter of 24.5% (range 1-49) after a median treatment time of 9.5 months. Only one patient receiving selpercatinib, with a tumoral reduction of 25%, could undergo surgery, resulting in an R2 resection due to extensive mediastinal extension.Three patients with ATC showed a median tumor diameter reduction of 42% (range 6.7-50) after a median treatment time of 2 months. Two patients underwent surgical intervention and achieved R1 and R2 resection, respectively. While neoadjuvant therapy achieved tumoral responses, surgical resection was feasible in 50% of DTC, 33% of ATC, and 16% of MTC patients, with R0/R1 resection in 26% of the cohort, underscoring the need for patient selection and further research in this area.

Molecular characterization of circulating tumor cells (CTCs) in sporadic medullary thyroid carcinoma (spMTC) patients

Molecular characterization of circulating tumor cells (CTCs) in sporadic medullary thyroid carcinoma (spMTC) patients

Does the extent of neck surgery based on preoperative calcitonin level influence survival in medullary thyroid carcinoma: a retrospective tertiary centre experience.

Medullary thyroid carcinoma (MTC) is a rare thyroid cancer arising from the calcitonin-secreting parafollicular cells. Previous studies suggested a preoperative calcitonin level >200ng/l is an indication for prophylactic lateral neck dissection (LND) to remove micrometastases and improve survival outcomes. This retrospective single-centre study assessed the efficacy of preoperative calcitonin levels as a marker for determining need for prophylactic LND in MTC. Data were obtained on demographics, preoperative calcitonin levels, size and laterality of index tumour, type of neck dissection (central neck dissection (CND), LND), nodes removed, levels with involved nodes, number of nodes histologically involved, mortality, adjuvant therapy and locoregional recurrence. A total of 33 patients were identified from St George's University Hospitals NHS Foundation Trust between 1 January 2001 and 19 August 2021; 8 were excluded for data quality issues. Of the 18 classified with a high preoperative calcitonin level (>200ng/l), 10 (56%) had a LND and 8 (44%) had a CND. In the low-calcitonin group, three (43%) patients had a CND only and four (57%) had a LND. There was no difference in absolute or disease-free survival between the low and high groups (p=0.960, p=0.817), or between those who had a CND and LND in the high-calcitonin group (p=0.607, hazard ratio (HR) 0.55; p=0.129, HR 8.78). There was no statistically significant difference in outcomes between high and low calcitonin groups. A selective approach to performing LND in MTC patients based on clinical and imaging findings suggesting disease presence in the lateral neck should be explored further.

Next-Generation Sequencing in Sporadic Medullary Thyroid Cancer Patients: Mutation Profile and Disease Aggressiveness.

Next-generation sequencing (NGS) analysis of sporadic medullary thyroid carcinoma (sMTC) has led to increased detection of somatic mutations, including RET M918T, which has been considered a negative prognostic indicator. This study aimed to determine the association between clinicopathologic behavior and somatic mutation identified on clinically motivated NGS. In this retrospective cohort study, patients with sMTC who underwent NGS to identify somatic mutations for treatment planning were identified. Clinicopathologic factors, time to distant metastatic disease (DMD), disease-specific survival (DSS), and overall survival (OS) were compared between somatic mutations. Somatic mutations were identified in 191 sMTC tumors, including RET M918T (53.4%), other RET codons (10.5%), RAS (18.3%), somatic RET indels (8.9%), and RET/RAS wild-type (WT) status (8.9%). The median age at diagnosis was 50 years (range, 11-83); 46.1% were female. When comparing patients with RET M918T, RET-Other, and RET WT (which included RAS and RET/RAS WT), there were no differences in sex, TNM category, systemic therapy use, time to DMD, DSS, or OS. On multivariate analysis, older age at diagnosis (HR 1.05, P < .001; HR 1.06, P< .001) and M1 stage at diagnosis (HR 3.17, P = .001; HR 2.98, P = .001) were associated with decreased DSS and OS, respectively, but mutation cohort was not. When comparing RET M918T to RET indels there was no significant difference in time to DMD, DSS, or OS between the groups. Somatic RET mutations do not portend compromised DSS or OS in a cohort of sMTC patients who underwent clinically motivated NGS.

Serum Biochemical Markers for Medullary Thyroid Carcinoma: An Update.

Medullary thyroid carcinoma (MTC), a rare malignancy, requires early diagnosis for optimal patient outcomes. An important aspect of MTC diagnosis is the assessment of serum biomarkers. This review aimed to evaluate the use of serum biomarkers in the diagnosis, prognosis, and follow-up of MTC. A thorough search of PubMed covering 1975 to 2022 was conducted to identify English-language articles on MTC serum biomarkers. The review revealed that calcitonin (Ctn) and carcinoembryonic antigen (CEA) remain the most important serum biomarkers for MTC diagnosis and management. Despite limited studies on procalcitonin (PCT), its stability and ability to exclude interference from inflammation make it a valuable potential marker of MTC. Although the positive rate of serum CA19-9 levels in MTC patients was not high, it can be used as an indicator of poor prognosis in advanced MTC. Other serum markers, including chromogranin A, gastrin-releasing peptide precursor, and neurospecific enolase, did not show any unique value in MTC diagnosis and management. Taken together, this review emphasized the importance of serum biomarkers, particularly Ctn and CEA, in the diagnosis and management of MTC. PCT shows promise as a valuable potential marker, whereas CA19-9 can be used as a prognostic indicator of advanced MTC. Further research is needed to validate the significance of these serum biomarkers in MTC and determine the effects of confounding factors on their levels. Clinicians should consider using these markers in MTC diagnosis, prognosis, and follow-up, particularly for patients with advanced disease.

Abstract 4665: USP18 promotes anlotinib resistance in medullary thyroid carcinoma by stabilizing aurora B kinase

Abstract Targeted therapy resistance is the main cause of disease progression in advanced medullary thyroid carcinoma (MTC). However, the key molecules and mechanisms remain unclear. We previously performed a genome-wide in vitro screen of Anlotinib resistance-related genes in human MTC cell line TT using CRISPR-dCas9-SAM system and identified ubiquitin-specific protease 18 (USP18) as a key molecule mediating Anlotinib resistance in MTC. However, its downstream mechanism needs further clarification. Based on the high-throughput DNA sequencing results of the control group and the Anlotinib screening group, a group of key genes related to Anlotinib resistance in MTC was screened through the MAGeCK algorithm and the enrichment ratio of sgRNA in the Anlotinib screening group. Among them, USP18 ranked first in the enrichment results. Analysis of the correlation between the expression level of USP18 in MTC patient specimens and survival revealed that patients with high USP18 expression in tumor cells had poorer prognosis. Overexpression of USP18 in MTC tumor cells significantly promoted the growth of subcutaneous xenograft tumors in NOD/SCID mice treated with Anlotinib. In vitro cell experiments also showed that overexpression of USP18 promoted the proliferation of MTC tumor cells and significantly inhibited the proportion of cell apoptosis after Anlotinib treatment. Further research found that USP18, as a deubiquitinating enzyme that can specifically remove ISG15-like ubiquitin-like proteins from substrate proteins, can improve the kinase stability of Aurora B by removing ISG15-like ubiquitin modification and promote MTC tumor cell proliferation through the activation of PI3K-Akt signaling regulated by Aurora B kinase. Application of Aurora B kinase inhibitor in Anlotinib-resistant MTC cell lines significantly inhibited tumor cell proliferation, and Aurora B kinase inhibitor significantly increased the proportion of cell apoptosis in MTC tumor cells overexpressing USP18. In the subcutaneous xenograft tumor model of MTC in NOD/SCID mice, the growth of xenograft tumors in the Anlotinib combined with Aurora B kinase inhibitor treatment group was also significantly inhibited. In summary, overexpressed USP18 can activate PI3K-Akt signaling and promote tumor cell proliferation by increasing the stability of Aurora B kinase, ultimately leading to the formation of Anlotinib resistance in MTC patients. Combined use of Aurora B kinase inhibitor is a potentially effective combined treatment strategy for Anlotinib-resistant MTC patients. Citation Format: Xuan Qin, Xing Wan, Dapeng Li, Yimeng Liu, Xianhui Ruan, Fangkun Luan, Kejia Xu, Jia Li, Rong Xiang, Yongjun Piao, Yi Shi, Xiangqian Zheng. USP18 promotes anlotinib resistance in medullary thyroid carcinoma by stabilizing aurora B kinase [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 4665.

Abstract 5835: Genome-Wide CRISPR gene knockout screens combined with selpercatinib identifies potent combination therapies for RET driven medullary thyroid carcinoma

Abstract Background: Medullary thyroid carcinoma (MTC) is a rare neuroendocrine tumor driven primarily by activating mutations in the RET proto-oncogene. It accounts for approximately 13% of thyroid cancer-related deaths. Total thyroidectomy is the main treatment option for MTC patients; however, its efficacy is limited due to the high prevalence of metastatic disease at diagnosis. Vandetanib, cabozantinib, and selpercatinib are RET signaling inhibitors (RETi), that have been approved for treating advanced MTC. Despite their effectiveness, many patients relapse or have refractory disease due to eventual resistance to these RETis. Methods: In our study, we employed genome-wide clustered regularly interspaced short palindromic repeats (CRISPR) gene knockout (KO) in MTC cell lines treated with selpercatinib or vehicle to investigate the genetic mechanisms of resistance or sensitivity to RETi. Our overarching goal was to identify potential synergistic or additive drug combinations that may prevent or treat resistant disease. Results: Our research identified key genes and pathways confirming the sensitivity or resistance of MTC cells to RETi. Notably, apoptotic genes along with RAS and mTOR signaling pathways were found to play a significant role in resistance development. Knocking out negative regulators of these pathways (such as NF1 and TSC2) conferred growth advantages to cells treated with RETi. Alternatively, knocking out BCL2, an antiapoptotic protein, led to increased lethality. These findings suggested that targeting RAS, mTOR, or antiapoptotic pathways in conjunction with RETi may be synergistic or have additive activity. To validate the CRISPR screening, we selectively knocked down NF1 in MTC cells and found it led to a nearly two-fold increase in IC50 for selpercatinib. Furthermore, in-vitro and in-vivo testing confirmed significant synergistic activity when using the combination of trametinib, an MEK inhibitor (MEKi; downstream of the RAS pathway), with selpercatinib. Conclusions and Future Directions: We have identified a potent synergistic combination of MEKi with RETi as a novel synergistic drug combination to treat MTC, which may also prevent resistance to RETi. These results will be translated to patients through clinical trials conduced at the NCI. Citation Format: Abdelrahman Rahmy, Arwa Fallatah, David Milewski, Meijie Tian, Young Song, Yong Kim, Hsien-Chao Chou, Xinyu Wen, Chaoyu Wang, Jun Wei, Robert Hawley, John Glod, Javed Khan. Genome-Wide CRISPR gene knockout screens combined with selpercatinib identifies potent combination therapies for RET driven medullary thyroid carcinoma [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 5835.

Combining radiomics with thyroid imaging reporting and data system to predict lateral cervical lymph node metastases in medullary thyroid cancer.

Medullary Thyroid Carcinoma (MTC) is a rare type of thyroid cancer. Accurate prediction of lateral cervical lymph node metastases (LCLNM) in MTC patients can help guide surgical decisions and ensure that patients receive the most appropriate and effective surgery. To our knowledge, no studies have been published that use radiomics analysis to forecast LCLNM in MTC patients. The purpose of this study is to develop a radiomics combined with thyroid imaging reporting and data system (TI-RADS) model that can use preoperative thyroid ultrasound images to noninvasively predict the LCLNM status of MTC. We retrospectively included 218 MTC patients who were confirmed from postoperative pathology as LCLNM negative (n=111) and positive (n=107). Ultrasound features were selected using the Student's t-test, while radiomics features are first extracted from preoperative thyroid ultrasound images, and then a two-step feature selection approach was used to select features. These features are then used to establish three regularized logistic regression models, namely the TI-RADS model (TM), the radiomics model (RM), and the radiomics-TI-RADS model (RTM), in 5-fold cross-validation to determine the likelihood of the LCLNM. The Delong's test and decision curve analysis (DCA) were used to evaluate and compare the performance of the models. The ultrasound features of margin and TI-RADS level, and a total of 12 selected radiomics features, were significantly different between the LCLNM negative and positive groups (p<0.05). The TM, RM, and RTM yielded an averaged AUC of 0.68±0.05, 0.78±0.06, and 0.82±0.05 in the 5-fold cross-validation dataset, respectively. RM and RTM are statistically better than TM (p<0.05 and p<0.001) according to Delong test. DCA demonstrates that RTM brings more benefit than TM and RM. We have developed a joint radiomics-based model for noninvasive prediction of the LCLNM in MTC patients solely using preoperative thyroid ultrasound imaging. It has the potential to be used as a complementary tool to help guide treatment decisions for this rare form of thyroid cancer.

Enhancing Outcomes through Guideline Adherence in Medullary Thyroid Cancer Patients

Enhancing Outcomes through Guideline Adherence in Medullary Thyroid Cancer Patients

Ultrasonographic features of thyroid carcinoma of different sizes: comparison between medullary thyroid carcinomas and papillary thyroid carcinomas

Objective: To investigate the ultrasonographic features of medullary thyroid carcinomas (MTCs) of different sizes and supply valid information for separating MTCs from papillary thyroid carcinomas (PTCs). Methods: There were 87 patients with MTC and 220 patients with PTC detected by ultrasonography and confirmed by pathology at Tianjin Medical University Cancer Institute and Hospital from June 2018 to March 2022. Nodules were divided into the large nodule group (the maximum diameter of the tumor was＞1 cm) and the small nodule group (the maximum diameter of the tumor was ≤1 cm). There were 97 cases in the small nodule group, including 28 cases of MTC and 69 cases of PTC. There were 210 cases in the large nodule group, including 59 cases of MTC and 151 cases of PTC. After stratification by thyroid nodules, ultrasonographic features of thyroid nodules and metastatic lymph nodes, preoperative serum calcitonin (CT) and carcinoembryonic antigen (CEA) levels were compared between MTC and PTC patients. Results: In the small nodule group, the proportion of MTCs exhibiting hypoecho, smooth margins, and having blood flow signals was higher than that of PTCs, with statistically significant differences (all P＜0.05). In the large nodule group, the proportion of MTCs showing cystic solidity, hypoecho, smooth margins, blood flow, and the type Ⅳvascular distribution was higher than PTCs, and the difference of calcification type between them was also statistically significant (all P＜0.05). In contrast, the differences in the number of lesions and aspect ratio between MTCs and PTCs were not statistically significant regardless of nodule size (all P＞0.05). In the small nodule group,6 metastatic lymph nodes of medullary thyroid carcinoma (LNM-MTC) and 11 metastatic lymph nodes of papillary thyroid carcinoma (LNM-PTC) were correctly diagnosed by ultrasound, respectively. The diagnostic compliance rate of ultrasound was 78.6% (22/28) and 78.3% (54/69), respectively, with no statistically significant difference (P=0.973). In the large nodule group, 28 LNM-MTC and 11 LNM-PTC were correctly diagnosed by ultrasound, respectively. The diagnostic compliance of ultrasound was 88.1% (52/59) and 73.5% (111/151), respectively, which was statistically significant (P=0.022). Among them, 82.1% of LNM-MTC and 56.6% of LNM-PTC showed abnormal blood flow signals, with a statistically significant difference (P=0.016). There were significant differences in preoperative serum CT and CEA levels of different sizes of MTCs (all P＜0.05). Conclusions: Different sizes of MTCs require diverse demonstrative criteria. Abnormal blood flow signal is of great significance in the diagnosis of LNM-MTC. Within the absence of ultrasonic characteristics, preoperative serum CT test can provide confidence for the diagnosis of MTC.

Subgroup analysis of steadily increased trends in medullary thyroid carcinoma incidence and mortality in the USA, 2000-2020: a population-based retrospective cohort study.

The incidence rate of medullary thyroid carcinoma (MTC) continues to grow, along with its mortality rate in the USA. However, the subgroup trends in MTC have not yet been established. This population-based retrospective cohort study was based on the Surveillance, Epidemiology, and End Results (SEER) 17/12 registry database. Subgroup analysis was performed through clinicopathological and treatment-related characteristics. Annual average percentage change (AAPC) was calculated using joinpoint regression analysis. A total of 3833 MTC patients and 536 death cases were diagnosed in the SEER database. Between 2000 and 2019, the incidence (AAPC = 1.64) and mortality (AAPC = 3.46) rates of MTC continued to rise. Subgroup analysis showed the proportion of elderly patients (65-84 years) gradually increased in incidence between 2000 and 2020. Patients with early-stage tumors, such as tumors ≤20 mm, showed the same trends. Aspects of treatment, the implementation rate of total thyroidectomy (AAPC = 0.38) and lymph node dissection (AAPC = 1.06) also increased persistently in almost all of the age subgroups. The incidence and mortality of MTC consistently increased from 2000 to 2019. Subgroup analysis indicated a significant increase in elderly patients and early-stage patients, and more attention should be paid to the management of these increased subgroups.

Efficacy and safety of pralsetinib in Chinese advanced RET-mutant medullary thyroid cancer patients.

Pralsetinib has demonstrated efficacious activity in various solid tumors, including medullary thyroid cancer (MTC), as observed in the phase 1/2 global ARROW study (BLU-667-1101; NCT03037385). We evaluated the safety and efficacy of pralsetinib in Chinese patients with advanced RET-mutant MTC. In the extension cohort of ARROW, adult patients with advanced MTC, who had not received systemic therapy (except for cytotoxic chemotherapy), were treated with pralsetinib (400 mg once daily, orally). The primary endpoints were blinded independent central-reviewed (BICR) objective response rate (ORR) and safety. Between October 9, 2019, and April 29, 2020, 34 patients were enrolled at 12 centers across China. Among them, 28 patients tested positive for RET mutations in the central laboratory, and 26 of these, with measurable disease at baseline per BICR, were included in the analysis set for tumor response. As of April 12, 2021 (data cutoff), the ORR was 73.1% (95% CI: 52.2-88.4), and the median duration of response was not reached. The most common (≥15%) grade ≥3 treatment-related adverse events (TRAEs) in the 28 patients with RET-mutant MTC were neutrophil count decreased (8/28, 28.6%), blood creatine phosphokinase increased (6/28, 21.4%), and lymphocyte count decreased (5/28, 17.9%). Serious TRAEs were reported by six patients (21.4%), with the most common event being pneumonia (3/28, 10.7%). No patient discontinued treatment or died from pralsetinib-related adverse events. Pralsetinib demonstrated broad, deep, and durable efficacy, as well as a manageable and acceptable safety profile in Chinese patients with advanced RET-mutant MTC.

Novel prognostic nomogram for predicting recurrence-free survival in medullary thyroid carcinoma.

Recently, there have been attempts to improve prognostication and therefore better guide treatment for patients with medullary thyroid carcinoma (MTC). In 2022, the International MTC Grading System (IMTCGS) was developed and validated using a multi-institutional cohort of 327 patients. The aim of the current study was to build upon the findings of the IMTCGS to develop and validate a prognostic nomogram to predict recurrence-free survival (RFS) in MTC. Data from 300 patients with MTC from five centres across the USA, Europe, and Australia were used to develop a prognostic nomogram that included the following variables: age, sex, AJCC stage, tumour size, mitotic count, necrosis, Ki67 index, lymphovascular invasion, microscopic extrathyroidal extension, and margin status. A process of 10-fold cross-validation was used to optimize the model's performance. To assess discrimination and calibration, the area-under-the-curve (AUC) of a receiver operating characteristic (ROC) curve, concordance-index (C-index), and dissimilarity index (D-index) were calculated. Finally, the model was externally validated using a separate cohort of 87 MTC patients. The model demonstrated very strong performance, with an AUC of 0.94, a C-index of 0.876, and a D-index of 19.06. When applied to the external validation cohort, the model had an AUC of 0.9. Using well-established clinicopathological prognostic variables, we developed and externally validated a robust multivariate prediction model for RFS in patients with resected MTC. The model demonstrates excellent predictive capability and may help guide decisions on patient management. The nomogram is freely available online at https://nomograms.shinyapps.io/MTC_ML_DFS/.

Survival Outcomes of Medullary Thyroid Cancer With and Without Amyloid Deposition

ObjectiveAmyloid deposition within tumor stroma is a distinctive histologic feature of medullary thyroid cancer (MTC). However, its prognostic significance remains uncertain. We aimed to elucidate the impact of amyloid status on survival outcomes in a large cohort. MethodsThe Surveillance, Epidemiology, and End Results registry was queried to identify patients diagnosed with MTC from 2000 to 2019. Patients with amyloid-positive (International Classification of Diseases for Oncology, third edition code 8345/3) and amyloid negative (International Classification of Diseases for Oncology, third edition code 8510/3) tumors were analyzed. Overall and disease-specific survival were compared between matched cohorts using Kaplan-Meier and Cox proportional hazards analyses. ResultsOf the 2526 MTC patients, 511 of which were amyloid-positive and 2015 that were amyloid negative. Amyloid-positive patients displayed lower T stage (T3/4: 28% vs 85%, P < .001) and less extrathyroidal extension (11.3% vs 81.6%, P < .001). No difference in distant metastasis rate was observed between groups (14.5% vs 14.4%, P = .98). However, amyloid-positive patients showed a tendency for distal lymph node metastasis (1.2% vs 0.3%, P = .020). On univariate analysis, amyloid-positive status showed comparable overall survival times (mean 172.2 vs 177.8 months, P = .17), but a trend toward worse cancer-specific survival (hazard ratios [HR] = 1.31, 95% CI = 0.99-1.71, P = .051). After adjusting for covariates, amyloid deposition did not independently predict overall (HR = 1.15, 95% CI = 0.91-1.47, P = .25) or cancer-specific survival (HR = 1.30, 95% CI = 0.96-1.77, P = .09). Initiating therapy later than 1 month following diagnosis was associated with worse overall survival (HR = 1.25, 95% CI = 1.02-1.54, P = .029). ConclusionsThe presence of amyloid in MTC paradoxically associates with lower T stage yet exhibits a trend toward worse cancer-specific mortality. Amyloid deposition alone does not independently influence prognosis. Delayed treatment adversely impacted overall survival.

Machine Learning for Predicting Distant Metastasis of Medullary Thyroid Carcinoma Using the SEER Database.

We aimed to establish an effective machine learning (ML) model for predicting the risk of distant metastasis (DM) in medullary thyroid carcinoma (MTC). Demographic data of MTC patients were extracted from the Surveillance, Epidemiology, and End Results (SEER) database of the National Institutes of Health between 2004 and 2015 to develop six ML algorithm models. Models were evaluated based on accuracy, precision, recall rate, F1-score, and area under the receiver operating characteristic curve (AUC). The association between clinicopathological characteristics and target variables was interpreted. Analyses were performed using traditional logistic regression (LR). In total, 2049 patients were included and 138 developed DM. Multivariable LR showed that age, sex, tumor size, extrathyroidal extension, and lymph node metastasis were predictive features for DM in MTC. Among the six ML models, the random forest (RF) had the best predictability in assessing the risk of DM in MTC, with an accuracy, precision, recall rate, F1-score, and AUC higher than those of the traditional binary LR model. RF was superior to traditional LR in predicting the risk of DM in MTC and can provide a valuable reference for clinicians in decision-making.

The Establishment and Verification of a Nomogram Model for Predicting the Overall Survival of Medullary Thyroid Carcinoma: An Analysis Based on the SEER Database.

(1) Background: This study aimed to establish a nomogram model for predicting the overall survival (OS) of medullary thyroid carcinoma (MTC) patients based on the Surveillance, Epidemiology, and End Results (SEER) database. (2) Methods: Patients with MTC in the SEER database from 2004 to 2015 were included and divided into a modeling group and an internal validation group. We also selected MTC patients from our center from 2007 to 2019 to establish an external validation group. Univariate and multivariate Cox regression analyses were used to screen for significant independent variables and to establish a nomogram model. Kaplan-Meier (K-M) curves were plotted to evaluate the influence of the predictors. The C-indexes, areas under the curves (AUCs), and calibration curves were plotted to validate the predictive effect of the model. (3) Results: A total of 1981 MTC patients from the SEER database and 85 MTC patients from our center were included. The univariate and multivariate Cox regression analyses showed that age, tumor size, N stage, and M stage were significant factors, and a nomogram model was established. The C-index of the modeling group was 0.792, and the AUCs were 0.811, 0.825, and 0.824. The C-index of the internal validation group was 0.793, and the AUCs were 0.847, 0.846, and 0.796. The C-index of the external validation group was 0.871, and the AUCs were 0.911 and 0.827. The calibration curves indicated that the prediction ability was reliable. (4) Conclusions: A nomogram model based on age, tumor size, N stage, and M stage was able to predict the OS of MTC patients.

Characterization of the Thyroid Cancer Genomic Landscape by Plasma-Based Circulating Tumor DNA Next-Generation Sequencing.

Background: The limited availability of targeted therapies in thyroid cancer (TC) has challenged conventional treatment algorithms and has established urgency for the identification of targetable genomic abnormalities. In addition to widely adopted tissue-based next-generation sequencing (NGS), plasma-based circulating tumor DNA (ctDNA) NGS is rapidly emerging as a genomic biomarker detection method and is steadily gaining utility across solid tumors. To date, plasma-based genomic alterations in TC have not been determined. Herein, we profile potential actionable mutations detected through ctDNA in patients with TC subtypes. Methods: A retrospective data analysis of the Guardant Health, Inc. database was performed using the commercially available Guardant360® plasma-NGS test on TC samples from adult patients collected between 2016 and 2021. The landscape of genomic alterations and blood tumor mutation burden (bTMB) were analyzed in patients with different types of TC: anaplastic TC (ATC), papillary TC (PTC), follicular TC (FTC), oncolytic carcinoma of the thyroid (OCA), poorly differentiated TC (PDTC), medullary TC (MTC), and TC not otherwise specified (TC NOS). Results: Of the 1094 patients included most of the patients n = 876 had TC NOS, and 20% had a specific diagnosis (92 ATC, 62 PTC, 14 FTC, 16 OCA, 2 PDTC, and 32 MTC patients). The median age was 65 (range 10-98) and 47.3% were male. 78.3% of patients had one or more genomic alteration detected by ctDNA NGS. TP53 (46.9%) was the most common mutation detected among all TC. BRAFV600E was detected in 27.2% of ATC, 35.7% of PTC, and in none of FTC. RAS was detected in 18.5% of ATC, 11.9% of PTC, and 62.5% of FTC. RET, ALK, and NTRK fusions were seen in 1.1%, 0.5%, and 0.2% of all TC, respectively. RET mutations were detected in 66.7% of MTC. bTMB analysis was performed on 159 patients. The mean bTMB was higher in ATC compared with other types of TC (p = 0.0011, 0.0557, and <0.0001, respectively). Conclusions: Plasma-based comprehensive NGS is a promising NGS method in TC; however, future validation of the clinical utility by analysis of paired tumor and plasma samples is needed.

68Ga-DOTATATE PET/CT on the Follow-up of Patients with Medullary Thyroid Carcinoma

The purpose of this study is to evaluate the impact of 68Ga-DOTATE PET/CT on the management of medullary thyroid carcinoma (MTC). Eighteen patients (9 males and 9 females) with MTC who underwent 68Ga-DOTATE PET/CT for elevated calcitonin(Ct) levels were included in this study. Histopathological data, laboratory findings, 68Ga-DOTATE PET/CT findings were evaluated for each patient. 68Ga-DOTATATE PET/CT imaging findings were negative in 5 of 18 patients (27.8%) and positive in 13 of 18 patients (72.2%). The mean Ct level of patients with positive findings was higher than others. 68Ga-DOTATATE PET/CT was insufficient for detecting liver metastases in two patients who exhibited hypermetabolic uptakes consistent with solitary metastases in the liver on 18FDG-PET/CT. We believe that 68Ga-DOTATATE PET/CT plays an important role in the management of MTC patients with recurrent or metastatic disease. Its sensitivity is directly proportional to the levels of serum Ct. However, it may have limitations in detecting liver metastases.

Decreasing utilization for postoperative radiation therapy in locoregionally advanced medullary thyroid cancer.

Use of postoperative radiation therapy (PORT) in locoregionally advanced medullary thyroid cancer (MTC) remains controversial. The objective was to evaluate the effect of PORT on locoregional control (LRC) and overall survival (OS). Retrospective cohort study of 346 MTC patients separated into PORT and no-PORT cohorts. Relative indications for PORT, as well as changes in patterns of treatment, were recorded. 49/346 (14%) received PORT. PORT was associated with worse OS; adjusted HR = 2.0 (95%CI 1.3-3.3). PORT was not associated with improved LRC, even when adjusting for advanced stage (Stage III p = 0.892; Stage IV p = 0.101). PORT and targeted therapy were not associated with improved OS compared to targeted therapy alone; adjusted HR = 1.2 (95%CI 0.3-4.1). Use of PORT in MTC has decreased and its indications have become more selective, coinciding with the advent of effective targeted therapies. Overall, PORT was not associated with improved LRC or OS.