Introduction: Medullary thyroid carcinoma (MTC) comprises sporadic and hereditary forms, the latter commonly associated with multiple endocrine neoplasia type 2 (MEN2) which is identifiable through genetic screening of germline RET protooncogene. We compared the clinicopathological features and outcomes of hereditary and sporadic MTC in our single centre. Methodology: We conducted a retrospective audit of patients with MTC from 2000 to 2026. Patients were classified as either hereditary or sporadic based on genetic testing and/or family history of MTC/MEN2A syndrome. Variables analyzed included age at diagnosis, mode of presentation, pre-operative calcitonin, tumor size, lymph node (LN) involvement, post-operative biochemical cure, repeat surgery and presence of structural residual/recurrent disease. Results: A total of 57 patients were included (18 hereditary [31.6%], 39 presumed sporadic [68.4%]) with a median follow-up of 7.5 years (IQR 1.5–12.4). Hereditary MTC was diagnosed at a significantly younger age than sporadic MTC (33.0 vs. 44.7 years, p = 0.010) where 33% of the cases were diagnosed via screening detection whereas sporadic MTC more commonly presented with symptomatic neck swelling (84.6% vs. 50.0%, p = 0.008). There were no significant differences in median pre-operative calcitonin (513.5 vs. 1148.0 pg/mL, p = 0.101), tumor size (24.5 vs. 22.5 mm, p = 0.301), or LN involvement (41.7% vs. 61.5%, p = 0.307) between hereditary and sporadic MTC. Long-term outcomes were also comparable, with no differences in biochemical status, need for repeat surgery or residual/recurrent structural disease. Conclusion Hereditary MTC presents earlier and is more frequently detected due to screening, whereas sporadic MTC often presents symptomatically. Long-term outcomes are not primarily determined by hereditary status alone. Early access to RET mutation testing with a view to initiating prophylactic treatments rather than post detection surgery may improve disease burden.
Thyroid Neoplasms ; Cohort Studies

Introduction: Parathyroid carcinoma is a rare endocrine malignancy found in 1–5% of patients with primary hyperparathyroidism. It commonly presents with severe hypercalcemia and markedly elevated parathyroid hormone (PTH) levels. We report a challenging case of parathyroid carcinoma presenting with refractory hypercalcemia with incidental papillary thyroid microcarcinoma. Case: A 63-year-old female with hypertension, diabetes mellitus, dyslipidemia, and ischemic heart disease had been followed for primary hyperparathyroidism since 2014 (PTH5.5 pmol/L, calcium range 2.3–4.7 mmol/L). Initial neck ultrasound was suggestive of parathyroid adenoma over left side, but parathyroid scintigraphy failed to localize a lesion. She refused surgical intervention initially until April 2025, then she later agreed. Re-evaluation prior to operation revealed PTH level 76 pmol/L, and repeated parathyroid scintigraphy showed mild sestamibi avid uptake on left thyroid nodule. While awaiting surgery, she was admitted with a hypercalcemic crisis (serum calcium 3.7–5.38 mmol/L), complicated with acute kidney injury. Repeated ultrasound neck revealed extrathyroidal lesion adjacent to inferior pole of left thyroid (1.6 × 1.7 × 1.2 cm). She required aggressive intravenous hydration, intravenous pamidronate, calcitonin, and Denosumab to optimize her calcium level peri-operatively. She underwent left neck exploration with en-bloc left inferior parathyroidectomy, left hemithyroidectomy, and central neck dissection in November 2025. Histopathological examination confirmed parathyroid carcinoma (pT3N1) with nodal metastasis (1/4 lymph nodes positive) and an incidental papillary thyroid microcarcinoma measuring 1 mm (pT1a). Conclusion This case highlights the challenges of perioperative hypercalcemia management in parathyroid carcinoma. Effective preoperative control often requires multiple treatment modalities. Severe refractory hypercalcemia and high PTH level should raise a high index of suspicion for malignancy. Early complete resection is the cornerstone of treatment and is associated with optimal outcomes.
Papillary Thyroid Microcarcinoma ; Calcium ; Parathyroid Neoplasms

Introduction: Medullary thyroid carcinoma (MTC) has the highest familial predisposition syndrome of any hereditary cancer syndrome. The most common subtype of hereditary MTC is multiple endocrine neoplasia type 2A (MEN2A), which is an autosomal dominant syndrome characterized by MTC, pheochromocytoma, and primary hyperparathyroidism (HPP). This study evaluates the genotypic distribution, phenotypic manifestations, and clinical characteristics of MEN2A within a retrospective MTC cohort. Methodology: A retrospective audit of MTC patients was conducted at a tertiary centre. Patients with clinically or genetically confirmed hereditary MTC were identified for further analysis. Electronic medical records were reviewed for demographic data, RET germline mutations, occurrence of pheochromocytoma and HPP, laterality of disease, and documented surgical interventions. Results: In all, 18 patients (31.6%) were classified as hereditary from a cohort of 57 patients with a median age at diagnosis of 29.2 years. Among genetically confirmed cases with available variant data (n = 11), mutations predominantly involved exon 11 codon 634 (90.9%, n = 10), including p.Cys634Arg (n = 4), p.Cys634Tyr, and p.Cys634Ser, with one codon 618 mutation. Extrathyroidal manifestations were common. Pheochromocytoma occurred in 50.0% (n = 9), of which 77.8% (n = 7) were bilateral. Most patients underwent adrenalectomy, including bilateral procedures in those with bilateral disease. HPP was identified in 44.4% (n = 8), managed with selective parathyroidectomy. Both pheochromocytoma and HPP were present in 22.2% (n = 4), while isolated MTC occurred in 27.8% (n = 5). Conclusion Hereditary MTC in our cohort is predominantly associated with high-risk codon 634 RET mutations and demonstrates substantial penetrance of pheochromocytoma and HPP. The high frequency of bilateral adrenal involvement highlights the importance of systematic biochemical surveillance and appropriately timed surgical management in MEN2A. A nationwide registry would be timely.
Humans ; Multiple Endocrine Neoplasia Type 2a ; Thyroid Neoplasms

Introduction: Discordant thyroid function tests (TFTs), characterized by elevated free thyroxine 4 (FT4) with non-suppressed thyroid-stimulating hormone (TSH), pose a significant diagnostic challenge. Differentiating between Resistance to Thyroid Hormone (RTH) and TSH-secreting pituitary adenoma (TSH-oma) is essential, as management strategies differ substantially. Case: A female with a history of hyperthyroidism diagnosed in 2011 was treated with antithyroid drugs for 1 year before defaulting on follow-up. She was later found to have discordant TFTs at a private centre, where a brain computed tomography scan was reportedly normal. She was referred to our centre for optimization of thyroid function prior to planned thyroidectomy for a solitary large right thyroid nodule measuring 4.2 × 2.8 × 4.7 cm. Fine-needle aspiration cytology demonstrated a benign follicular lesion (Bethesda II). Despite restarting antithyroid medication, she remained clinically euthyroid with no overt thyrotoxic symptoms apart from intermittent palpitations without documented tachycardia. Antithyroid therapy was discontinued. Serial TFTs across multiple assay platforms consistently demonstrated elevated FT4 with inappropriately normal TSH levels. Thyroid autoantibodies, including TSH receptor and anti-thyroid peroxidase antibodies, were negative. Pituitary magnetic resonance imaging showed no evidence of adenoma, and serum α-subunit level was normal (0.3 ng/ mL), making TSH-oma unlikely. Dynamic testing was not performed as thyrotropin-releasing hormone stimulation was unavailable at our centre, while T3 suppression testing was deemed inappropriate due to symptomatic palpitations. Family screening was not possible as the patient was not in contact with her relatives. In the absence of pituitary pathology and given her largely euthyroid clinical status, RTH was considered the most likely diagnosis. Conclusion This case highlights the importance of considering RTH in patients with persistent discordant TFTs, particularly when clinical findings do not correlate with biochemical abnormalities. Early recognition and appropriate pituitary evaluation are essential to prevent misdiagnosis and avoid unnecessary antithyroid therapy or thyroidectomy.
Pituitary Neoplasms ; Thyroid Hormones ; Thyrotropin

INTRODUCTION

Papillary thyroid cancer (PTC) is generally considered to be an indolent disease with relatively good prognosis. However, some studies have shown that the Filipino population has a higher risk for disease recurrence compared to non-Filipino patients and hence early identification and management during the follow-up period would be beneficial, especially those in whom risk factors for recurrence were identified.

This study aims to identify determinants for disease recurrence of patients with papillary thyroid carcinoma (as defined by the American Thyroid Association (ATA) guidelines 2015) diagnosed from January 1, 2013-December 31, 2017, seen at the University of Santo Tomas Hospital (USTH) outpatient endocrine clinic and underwent total thyroidectomy with or without radioactive iodine ablation therapy.

Retrospective review of outpatient medical records of 82 patients with PTC who underwent total thyroidectomy with or without radioactive iodine (RAI) therapy and achieved excellent response (ER) to therapy was performed. Baseline clinical profile such as age at diagnosis, sex, family history of thyroid cancer, family history of goiter, histopathology result, serial thyroglobulin (Tg), anti-thyroglobulin (anti-Tg) levels, whole body scan reports, neck ultrasound reports and RAI doses were collected. Logistic regression analysis was used to identify determinants to the development of worsening response.

Of the 82 patients, 18 (21.9%) developed worsening response to therapy. Predictors of poor outcomes identified from previous studies such as age, sex, extent of disease, size and multifocality of tumors, ATA risk classification and initial dynamic risk assessment, RAI therapy, level of thyroid-stimulating hormone (TSH) suppression were analyzed. After logistic regression analysis, there was no significant association between variables and progression to worsening response that were previously identified in other studies.

Even though no significant association between investigated variables and worsening response were identified in this study, previous studies with larger populations that had exhibited positive association should be considered and hence current Philippine guidelines for the management of PTC must still be applied.

OBJECTIVES: To investigate the expression of apolipoprotein C1 (APOC1) in papillary thyroid carcinoma (PTC) and its effects on proliferation and apoptosis of PTC cells. METHODS: The expression level of APOC1 in PTC and its impact on prognosis were analyzed using GEPIA 2 and Kaplan-Meier databases. Immunohistochemistry (IHC) and Western blotting were used to detect the expression of APOC1 in PTC and adjacent tissues and in 3 PTC cell lines and normal thyroid Nthyori 3-1 cells. In TPC-1 and BCPAP cells, the effect of Lipofectamine 2000-mediated transfection with APOC1 siRNA or an APOC1-overexpressing plasmid on cell growth and colony formation ability were examined by observing the growth curves and using colony-forming assay. The changes in cell cycle and apoptosis of the transfected cells were analyzed with flow cytometry. RT-qPCR and Western blotting were used to detect the changes in expressions of P21, P27, CDK4, cyclin D1, Bcl-2, Bax, caspase-3 and caspase-9 and the key proteins in the JAK2/STAT3 signaling pathway. RESULTS: APOC1 expression was significantly higher in PTC tissues and the 3 PTC cell lines than in the adjacent tissues and Nthyori 3-1 cells, respectively. In TPC-1 and BCPAP cells, APOC1 knockdown obviously reduced cell proliferative activity, increased the percentage of G0/G1 phase cells, lowered the percentages of S and G2 phase cells, promoted cell apoptosis, and downregulated mRNA and protein expression levels of CDK4, cyclin D1 and Bcl-2 and the protein levels of p-JAK2 and p-STAT3. APOC1 overexpression in the cells produced the opposite effects on cell proliferation, apoptosis, cell cycle and the mRNA and protein expressions. The application of AG490, a JAK2 inhibitor, strongly attenuated APOC1 overexpression-induced activation of the JAK2/STAT3 signaling pathway in BCPAP cells. CONCLUSIONS APOC1 overexpression promotes proliferation and inhibits apoptosis of PTC cells possibly by activating the JAK2/STAT3 signaling pathway and accelerating cell cycle progression.
Humans ; Apoptosis ; Cell Proliferation ; STAT3 Transcription Factor/metabolism* ; Signal Transduction ; Janus Kinase 2/metabolism* ; Thyroid Neoplasms/pathology* ; Thyroid Cancer, Papillary ; Cell Line, Tumor ; Carcinoma, Papillary

Thermal ablation has proven an effective treatment modality for certain thyroid diseases. However, its indications remain the subject of significant debate both domestically and internationally. Over recent years, several international academic organizations have issued consensus statements, position papers, and guidelines concerning thyroid thermal ablation. In China, the Chinese College of Interventionalists (CCI), in collaboration with other relevant academic organizations, released the "Expert consensus on thermal ablation for thyroid benign nodes, microcarcinoma and metastatic cervical lymph nodes (2018 edition)". This consensus statement received widespread recognition within the field and contributed significantly to the standardization of thyroid thermal ablation therapy in China. With the continuous accumulation of evidence-based medical data, the need for a more stringent and standardized approach to thyroid thermal ablation has become evident. Accordingly, the Interventional Ultrasound Committee of the CCI, in collaboration with multiple academic organizations and experts, conducted extensive discussions and multiple revisions before finalizing the "Multidisciplinary expert consensus on thermal ablation for benign thyroid diseases, low-risk thyroid carcinoma, and metastatic cervical lymph nodes (2025 edition)". This updated consensus builds on the framework of the 2018 edition, refining indications and contraindications, emphasizing standardized treatment, and outlining future directions for research and clinical applications of thyroid thermal ablation technology.
Humans ; Thyroid Neoplasms/surgery* ; Consensus ; Lymphatic Metastasis ; Lymph Nodes/pathology* ; Thyroid Diseases/surgery*

Objective To investigate the value of the novel lymphatic contrast-enhanced ultrasound(LCEUS)and conventional venous contrast-enhanced ultrasound(VCEUS)in the differential diagnosis of benign and malignant cervical lymph nodes in patients with thyroid cancer. Methods Patients with suspected thyroid cancer underwent conventional ultrasound,VCEUS,and LCEUS examinations of cervical lymph nodes before biopsy.The diagnostic abilities of conventional ultrasound,VCEUS,and LCEUS were compared with pathological results as the golden standard. Results Forty-four patients with 52 lymph nodes were included in the final data.Thirty-eight metastatic lymph nodes were confirmed by pathological results,and 14 were benign.The diagnostic sensitivity,specificity,and accuracy were 97.37%,71.43%,and 90.38% for LCEUS,92.11%,35.71%,and 76.92% for VCEUS,and 94.74%,21.43%,and 75.00% for conventional ultrasound,respectively.The area under the curve of LCEUS analyzed by the receiver operating characteristic curve was greater than that of VCEUS(P=0.020)and conventional ultrasound(P<0.001). Conclusion LCEUS could significantly improve the differential diagnosis of cervical lymph node metastasis in the patients with thyroid cancer,providing a basis for precise clinical treatment.
Humans ; Thyroid Neoplasms/diagnostic imaging* ; Lymphatic Metastasis/diagnostic imaging* ; Diagnosis, Differential ; Female ; Male ; Middle Aged ; Ultrasonography ; Adult ; Lymph Nodes/pathology* ; Contrast Media ; Neck ; Aged ; Young Adult ; Adolescent ; Sensitivity and Specificity

Objective To analyze the cellular and histopathological characteristics of underdiagnosed thyroid nodules of Chinese thyroid imaging reporting and data system(C-TIRADS) categories 3 and 4a,thus improving the understanding of these lesions. Methods The data of ultrasound and fine needle aspiration cytology were collected from 683 nodules diagnosed based on pathological evidence in 549 patients undergoing thyroid surgery.The cellular and histopathological characteristics of C-TIRADS 3 and 4a nodules were analyzed. Results Two hundred and sixty-eight nodules were classified as C-TIRADS category 3,including 236 benign nodules,12 low-risk ones,and 20 (7.46%) malignant ones.Two hundred and twenty-one nodules were classified as C-TIRADS category 4a,including 133 benign nodules,7 low-risk ones,and 81 (36.65%) malignant ones.The malignancy rates differed between C-TIRADS 3 and 4a nodules (χ²=58.93,P<0.001),and both were higher than the recommended malignancy rate in the guidelines for malignancy risk stratification of thyroid nodules (C-TIRADS) (both P<0.001).According to the pathological evidence,the underdiagnosed C-TIRADS 3/4a nodules were mainly papillary thyroid carcinoma,especially in patients with Hashimoto thyroiditis.There was not a consistent one-to-one match between each ultrasound result and each cytological classification of low-risk thyroid nodules.Conclusions When the malignant features in preoprative ultrasound imaging are atypical or absent,papillary thyroid carcinoma (especially with Hashimoto thyroiditis),follicular carcinoma,and medullary carcinoma are likely to be underdiagnosed as C-TIRADS 3 or 4a nodules.Therefore,efforts should be made to fully understand the cellular and pathological characteristics of these lesions.
Humans ; Thyroid Nodule/diagnostic imaging* ; Female ; Male ; Middle Aged ; Adult ; Ultrasonography ; Biopsy, Fine-Needle ; Aged ; Young Adult ; Thyroid Neoplasms/diagnostic imaging* ; Adolescent

Objective To analyze the ultrasonographic features of secondary squamous cell carcinoma of the thyroid(SSCC-T)and evaluate the diagnostic value of ultrasound.Methods A retrospective analysis was conducted on clinical and ultrasonographic data from 12 patients with pathologically confirmed SSCC-T treated at Beijing Friendship Hospital,Capital Medical University between January 2016 and January 2025.Evaluated parameters included lesion size,echogenicity,edge,vascularity,calcification,and cervical lymph node metastasis.Descriptive statistical analysis was performed to analyze the ultrasonographic features of SSCC-T,and Fisher's exact test was conducted to analyze the correlation between different ultrasound classifications and thyroid dysfunction.Results The 12 patients showed the following ultrasound classifications:nodular type(50.0%,6/12),diffuse type(33.3%,4/12),and mixed type(16.7%,2/12).All diffuse-type patients exhibited a characteristic cord-like hypoechoic pattern.Cervical lymph node metastasis was observed in all the patients,with 75.0%(9/12)showing lymph nodes >2 cm in maximum diameter.Thyroid dysfunction occurred in 66.7%(8/12)of patients,including 2 patients with dynamic shifts from hyperthyroidism to hypothyroidism.Diffuse and mixed types were associated with hypothyroidism(P=0.038).Conclusions SSCC-T demonstrates specific ultrasonographic features,particularly the cord-like hypoechoic pattern in the diffuse type.For patients with squamous cell carcinoma,regular ultrasound examinations of the thyroid and cervical lymph nodes combined with changes in thyroid function are conducive to the timely detection of thyroid metastasis of squamous cell carcinoma.
Humans ; Retrospective Studies ; Ultrasonography ; Carcinoma, Squamous Cell/diagnostic imaging* ; Thyroid Neoplasms/diagnostic imaging* ; Lymphatic Metastasis ; Male ; Female ; Middle Aged ; Thyroid Gland/diagnostic imaging* ; Adult