Surgical management of medullary thyroid carcinoma

Ultrasound Radiomics for Preoperative Prediction of Cervical Lymph Node Metastasis in Medullary Thyroid Carcinoma

Aims/Background Medullary thyroid carcinoma (MTC) is a rare thyroid malignancy with a high mortality rate. Early detection of cervical lymph node metastasis (LNM) is critical for improving prognosis for patients with MTC. This study aimed to investigate the predictive utility of ultrasound-based radiomics for preoperative prediction of cervical LNM in MTC patients. Methods The clinical, ultrasound, and pathological information of 193 patients with MTC were retrospectively examined. Radiomics features were obtained from the ultrasound images using PyRadiomics. The selected patients were randomly divided into training (n = 135) and validation (n = 58) cohorts. In the training dataset, radiomics features were selected using the least absolute shrinkage and selection operator (LASSO) regression, and the univariate and multivariate logistic regression tests were employed to identify the clinical independent predictors of cervical LNM. Three models were created: radiomics, clinical, and combined models, with the latter presented as a nomogram. The area under the curve (AUC) was calculated to evaluate the models' predictive performance. The differences in AUCs between the combined and approach-specific models were compared using the DeLong test. The clinical usefulness of the models was evaluated using decision curve analysis (DCA). Results Nineteen radiomics features were chosen, and the AUCs of the developed radiomics model in the training and validation datasets were 0.881 and 0.859, respectively. Tumour diameter, calcitonin (Ctn) level, tumour margin, and sonographers' suspicion of cervical LNM based on ultrasound findings were clinical independent predictors for cervical LNM. The AUCs of the clinical model built using these predictors were 0.800 and 0.805 in the training and validation datasets, whereas the combined model had much-improved AUCs, measuring 0.925 for the training dataset and 0.918 for the validation test. The DeLong test indicated a significant AUC difference between the combined and clinical models (training dataset p < 0.001, validation dataset p = 0.027), but the difference between the combined and radiomics models was significant only in the training dataset (training dataset p = 0.021, validation dataset p = 0.066). Furthermore, based on the DCA results, the combined model features the largest clinical net benefit. Conclusion The nomogram, the combined model merging the ultrasound-based radiomics with clinical independent predictors, effectively predicts preoperative cervical LNM in MTC patients, outperforming the radiomics and clinical models.

Fundamentals and recent advances in the evaluation and management of medullary thyroid carcinoma

Medullary thyroid carcinoma (MTC) is a rare primary neuroendocrine thyroid carcinoma that is distinct from other thyroid or neuroendocrine cancers. Most cases of MTC are sporadic, although MTC exhibits a high degree of heritability as part of the multiple endocrine neoplasia syndromes. REarranged during Transfection (RET) mutations are the primary oncogenic drivers and advances in molecular profiling have revealed that MTC is enriched in druggable alterations. Surgery at an early stage is the only chance for cure, but many patients present with or develop metastases. C-cell-specific calcitonin trajectory and structural doubling times are critical biomarkers to inform prognosis, extent of surgery, likelihood of residual disease, and need for additional therapy. Recent advances in the role of active surveillance, regionally directed therapies for localized disease, and systemic therapy with multi-kinase and RET-specific inhibitors for progressive/metastatic disease have significantly improved outcomes for patients with MTC.

Molecular genetics, therapeutics and RET inhibitor resistance for medullary thyroid carcinoma and future perspectives

Medullary thyroid carcinoma (MTC) is a rare type of thyroid malignancy that accounts for approximately 1-2% of all thyroid cancers (TCs). MTC include hereditary and sporadic cases, the former derived from a germline mutation of rearrangement during transfection (RET) proto-oncogene, whereas somatic RET mutations are frequently present in the latter. Surgery is the standard treatment for early stage MTC, and the 10-year survival rate of early MTC is over 80%. While for metastatic MTC, chemotherapy showing low response rate, and there was a lack of effective systemic therapies in the past. Due to the high risk (ca. 15-20%) of distant metastasis and limited systemic therapies, the 10-year survival rate of patients with advanced MTC was only 10-40% from the time of first metastasis. Over the past decade, targeted therapy for RET has developed rapidly, bringing hopes to patients with advanced and progressive MTC. Two multi-kinase inhibitors (MKIs) including Cabozantinib and Vandetanib have been shown to increase progression-free survival (PFS) for patients with metastatic MTC and have been approved as choices of first-line treatment. However, these MKIs have not prolonged overall survival (OS) and their utility is limited due to high rates of off-target toxicities. Recently, new generation TKIs, including Selpercatinib and Pralsetinib, have demonstrated highly selective efficacy against RET and more favorable side effect profiles, and gained approval as second-line treatment options. Despite the ongoing development of RET inhibitors, the management of advanced and progressive MTC remains challenging, drug resistance remains the main reason for treatment failure, and the mechanisms are still unclear. Besides, new promising therapeutic approaches, such as novel drug combinations and next generation RET inhibitors are under development. Herein, we overview the pathogenesis, molecular genetics and current management approaches of MTC, and focus on the recent advances of RET inhibitors, summarize the current situation and unmet needs of these RET inhibitors in MTC, and provide an overview of novel strategies for optimizing therapeutic effects.

A case report of diagnosis of liver metastasis of medullary thyroid carcinoma by multimodal ultrasound

Medullary thyroid carcinoma is a rare malignant neuroendocrine tumor. Distant metastasis is difficult to detect early. It is most common in lung, liver, bone and brain. This case was reported as liver metastasis of medullary thyroid carcinoma in an elderly woman, but routine ultrasound findings were atypical. After a series of relevant imaging examinations, contrast-enhanced ultrasound and ultrasound-guided puncture biopsy were used to confirm the nature of the intrahepatic lesions. Therefore, we believe that multimodal ultrasound is of great value in the diagnosis of liver metastasis of medullary thyroid carcinoma.

[Hereditary medullary thyroid cancer]

Parafollicular C cells progress via C cell hyperplasia to medullary thyroid cancer (MTC), which can be present even in the first years of life in multiple endocrine neoplasia (MEN) type 2A and 2B patients. Basal calcitonin and carcinoembryonic antigen (CEA) are useful tumor markers for the diagnosis and monitoring. The prognosis depends on the stage when the disease is diagnosed and there is a good genotype-phenotype correlation with the RET proto-oncogene, which can be used for estimation of the risk. The risk-stratified prophylactic thyroidectomy plays a decisive role in the prognosis of known gene mutation carriers.

Preoperative serum inflammation-based scores in medullary thyroid cancer

INTRODUCTION

Neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR) and systemic immune-inflammation index (SII) are prognostic factors in several tumours, though little is known in medullary thyroid cancer (MTC).

OBJECTIVE

To evaluate the association between preoperative NLR, PLR and SII with MTC clinicopathological and molecular features, and their predictive value for lymph node and distant metastasis.

METHODS

We retrospectively analysed 75 patients with MTC who underwent surgery at our institution. The familial form of MTC was found in 12% of patients.

RESULTS

In our cohort, 56% were females, the median age at diagnosis was 57 years (44-69), the median tumour diameter was 25mm (15-50); 21.3% were multifocal and 34.7% had extrathyroidal extension. Lymph node and distant metastasis were observed in 36 (48.0%) and 8 (10.7%) patients, respectively. Higher NLR was associated with preoperative calcitonin, angioinvasion, extrathyroidal extension, moderate/severe fibrosis; higher PLR was associated with extrathyroidal extension and advanced T stages; lower SII and NLR were associated with biochemical cure after surgery. Increased PLR, NLR and SII were associated with advanced MTC stages. In the univariate analysis, only NLR was associated with lymph node metastasis (odds ratio (OR)=2.69, 95% confidence interval (CI): 1.50-5.84; p=0.004); however, in the multivariate model, NLR was no longer a predictive factor for lymph node metastasis. None of these serum inflammatory markers predicted the occurrence of distant metastasis.

CONCLUSION

In conclusion, NLR, PLR and SII are associated with aggressive MTC, but do not predict lymph node or distant metastasis.

Management of medullary carcinoma of the thyroid: a review

Medullary thyroid carcinoma (MTC) is an uncommon malignancy of neuroendocrine origin derived from the parafollicular C cells. Although infrequent, the interest in this cancer exceeds its incidence owing to its distinctive features and its characteristic association with other endocrine tumors. Although the majority of MTCs are sporadic, hereditary varieties occur in isolation or as a part of multiple endocrine neoplasia type 2 syndrome (MEN 2). Currently, complete surgical resection of the tumor and nodal metastases with a curative intent remains the mainstay of therapy. The role of adjuvant therapy is limited, although radiotherapy and newer targeted therapies are routinely used for metastatic disease. The lack of consensus in the available guidance regarding the most appropriate diagnostic, therapeutic and follow-up strategies has caused substantial variability in clinical practice. Therefore, this review summarizes the latest available evidence and guidelines on the management of MTC with an emphasis on diagnosis, surgical treatment and follow-up.

Clinical Characteristics, Surgical Management, and Prognostic Factors of Medullary Thyroid Carcinoma: A Retrospective, Single-Center Study

Purpose: Medullary thyroid carcinoma (MTC) is a rare neuroendocrine malignancy with relatively early lymphatic metastatic spread. The clinical features of MTC remain controversial owing to the low incidence rate. This study aimed to analyze the clinical characteristics, prognostic factors, and long-term follow-up of MTC. Methods: Medical records of MTC patients treated at our hospital between December 2000 and November 2020 were reviewed retrospectively. Clinicopathologic features of MTC were analyzed using univariate and multivariate analyses. Cumulative survival rates were estimated using the Kaplan-Meier method. Results: In total, 152 patients with MTC were included. The rates of central and lateral lymph node metastases (LNM) were 52.0% and 42.8%, respectively. All patients were followed up with a median follow-up time of 43.5 (17.0-76.3) months. Univariate and multivariate analyses identified two independent factors associated with progressive disease. They were lateral LNM (p < 0.001) and lymph node ratio (LNR) >1/3 (p = 0.009). The 5-, 10-, and 15-year cumulative overall survival (OS) rates of MTC were 88.2%, 83.1%, and 76.2%, respectively. The 5-, 10-, and 15-year cumulative disease-free survival (DFS) rates were 61.8%, 48.6%, and 38.2%, respectively. Patients with stage I, II, and III disease had significantly longer OS and DFS than those with stage IV disease (p < 0.001). Conclusion: MTC is a rare endocrine malignancy and LNM is common. Patients with lateral LNM and LNR >1/3 are more likely to develop progressive disease. The long-term OS rates of MTC are good, but long-term DFS rates are poor.

Risk factors for lateral cervical lymph node metastasis in medullary thyroid carcinoma

: To investigate risk factors of lateral cervical lymph node metastasis (LLNM) in patients with medullary thyroid carcinoma (MTC). : Published studies regarding clinicopathological factors of LLNM in MTC were searched in PubMed, Web of Science, Embase, Cochrane library, Wanfang date and CNKI. Statistical analysis was performed using Stata 14.0 software. The mean and standard deviation from the sample size, range, median, and interquartile range was estimated. Odds ratio () or standard mean difference () with 95% confidence interval () of related factors were analyzed by fixed/random-effects models. Egger's test and Begg's test were applied to assess the publication bias of the literature. This study was registered with PROSPERO (CRD42021254955). : Fifteen studies involving 1424 patients were included in the analysis, among whom 543 cases had LLNM (38.13%). Meta-analysis revealed that an increased risk of LLNM was associated with male gender (1.64, 95%: 1.29-2.09, 4.06, 0.01), tumor diameter≥1cm (5.09, 95%: 2.43-10.67, 4.31, 0.01), multifocality (2.55, 95%: 1.79-3.61, 5.22, 0.01), capsule invasion (7.80, 95%: 4.84-12.55, 8.46, 0.01), extracapsular extension (9.46, : 5.66-15.81, 8.58, 0.01), cervical central lymph node metastasis (23.58, : 9.44-58.87, 6.77, 0.01), elevated preoperative calcitonin (1.17,95%: 0.67-1.67, 4.56, 0.01), spiculated margin on ultrasonography (4.32, 95%: 2.43-7.68, 4.99, 0.01), irregular shape on ultrasonography (6.81, : 3.64-12.73, 6.01, 0.01); while age ≥ 45 years (=1.22, 95%: 0.65-2.29, 0.62, >0.05), elevated preoperative carcinoembryonic antigen (0.95, : -0.48-2.38, 1.30, >0.05) and calcification on ultrasonography (1.28, 95%: 0.75-2.18, 0.92, >0.05) were not associated with LLNM. : Male gender, tumor diameter≥multifocality, capsule invasion, extracapsular extension, central lymph node metastasis, elevated preoperative calcitonin, spiculated margin and irregular shape on ultrasonography are risk factors for LLNM in MTC, when these clinical and ultrasonic features are present, lateral neck lymph node dissection is recommended.

Diagnostic Utility of Radiomics in Thyroid and Head and Neck Cancers

Radiomics is an emerging field in radiology that utilizes advanced statistical data characterizing algorithms to evaluate medical imaging and objectively quantify characteristics of a given disease. Due to morphologic heterogeneity and genetic variation intrinsic to neoplasms, radiomics have the potential to provide a unique insight into the underlying tumor and tumor microenvironment. Radiomics has been gaining popularity due to potential applications in disease quantification, predictive modeling, treatment planning, and response assessment - paving way for the advancement of personalized medicine. However, producing a reliable radiomic model requires careful evaluation and construction to be translated into clinical practices that have varying software and/or medical equipment. We aim to review the diagnostic utility of radiomics in otorhinolaryngology, including both cancers of the head and neck as well as the thyroid.

circPVT1 regulates medullary thyroid cancer growth and metastasis by targeting miR-455-5p to activate CXCL12/CXCR4 signaling

BACKGROUND

Medullary thyroid cancer (MTC) represents 13.4 % of all thyroid cancers-related deaths. The treatments for MTC are very limited especially for patients with distal metastasis. Therefore, it is critical to understand the mechanisms of MTC to pursue novel therapeutic avenues. Here, we studied the function of circPVT1/miR-455-5p in MTC.

METHODS

Human MTC tissues and cell lines were used. qRT-PCR and Western blotting were employed to measure expression levels of miR-455-5p, circPVT1, CXCL12, and epithelial mesenchymal transformation (EMT)-related proteins. Colony formation assay, flow cytometry, transwell assay, and scratch wound healing assay were used to assess the abilities of cell proliferation, apoptosis, migration and invasion, respectively. Dual luciferase assay and RNA immunoprecipitation were employed to validate interactions of circPVT1/miR-455-5p and miR-455-5p/CXCL12. Nude mouse xenograft model was used to evaluate the effects of shcircPVT1 and miR-455-5p mimics on tumor growth and metastasis in vivo.

RESULTS

miR-455-5p was reduced in MTC tissues and cells while circPVT1 was elevated. Their levels were correlated with prognosis of MTC. Overexpression of miR-455-5p or sh-circPVT1 suppressed EMT and MTC cell proliferation, migration and invasion. miR-455-5p targeted CXCL12 while circPVT1 sponged miR-455-5p. Knockdown of CXCL12 or CXCL12/CXCR4 signaling inhibitor reversed the effects of circPVT1 overexpression or miR-455-5p inhibitor on EMT and MTC cell proliferation, migration and invasion. Knockdown of circPVT1 or miR-455-5p overexpression repressed MTC tumor growth and lung metastasis in vivo.

CONCLUSIONS

miR-455-5p suppresses MTC growth and metastasis by targeting CXCL12/CXCR4 signaling pathway while circPVT1 promotes MTC by sponging miR-455-5p. Our study sheds light on the mechanisms of MTC growth and metastasis.

Medullary thyroid cancer: epidemiological pattern and factors contributing to recurrence and metastasis

INTRODUCTION

Medullary thyroid carcinoma (MTC) is a neuroendocrine thyroid carcinoma with parafollicular C cell differentiation. It can occur in either sporadic or hereditary form. Surgery is still the only curative treatment. The efficacy of chemotherapy and radiotherapy is poor.

METHODS

This was a retrospective study of 31 patients treated surgically for MTC in our oncology centre at Mansoura University between January 2008 and February 2019.

RESULTS

The mean age at diagnosis was 39.9 years. The median pathological size was 4cm. Multifocal disease was found in 12 patients and extrathyroid extension in 3 cases. Twenty patients were pathologically node positive. The median number of positive lymph nodes was four. Seven cases were metastatic at diagnosis. Local recurrence occurred in six individuals while distant recurrence occurred only in one. The median time from surgery to local recurrence was 12 months. The estimated mean disease free survival was 56.5 months. Disease free survival was significantly related to age, metastasis and side of nodal spread.

CONCLUSIONS

In our study cohort, the disease occurred predominantly in women and younger patients. Age, distant metastasis and nodal spread were the most significant prognostic factors. This study has also demonstrated that prognosis is not only affected by nodal involvement but also by side of involvement. The role of hemithyroidectomy in node negative unifocal disease with a small tumour size warrants further investigation.

Carcinoembryonic antigen should be concurrently checked with calcitonin to identify distant metastases in medullary thyroid cancer

Aim: This study investigates if serum calcitonin or carcinoembryonic antigen (CEA) levels can differentiate between locoregional and metastatic medullary thyroid cancer. Methods: A single institution retrospective analysis was performed on 88 patients with medullary thyroid cancer between 2008 and 2014. Results: In M0disease, calcitonin (p < 0.001) and CEA (p = 0.003) significantly decreased postoperatively. Not only was the correlation significant between calcitonin and CEA preoperatively (r = 0.72; p < 0.001) and postoperatively (r = 0.68; p < 0.001), calcitonin could extrapolate CEA levels (p < 0.001). These findings were statistically insignificant in metastatic disease. Conclusion: Independently, calcitonin and CEA fail to differentiate between locoregional and metastatic disease. Both are essential for prognostication: loss of concordance is suspicious for metastatic disease. Hence, discordant CEA and calcitonin levels should be an indication to pursue additional imaging.

Risk Factors for Lateral Lymph Node Metastases in Patients With Sporadic Medullary Thyroid Carcinoma

PURPOSE

Medullary thyroid carcinoma is a rare endocrine malignancy; 75% of patients with this disease have sporadic medullary thyroid carcinoma. While surgery is the only curative treatment, the benefit of prophylactic lateral neck dissection is unclear. This study aimed to analyze the clinicopathological risk factors associated with lateral lymph node metastases and determine the indication for prophylactic lateral neck dissection in patients with sporadic medullary thyroid carcinoma.

METHODS

The medical records of patients with medullary thyroid carcinoma who were treated at our hospital between January 2002 and January 2020 were retrospectively reviewed; a database of their demographic characteristics, test results, and pathological information was constructed. The relationship between lateral lymph node metastases and clinicopathologic sporadic medullary thyroid carcinoma features were analyzed using univariate and multivariate analyses.

RESULTS

Overall, 125 patients with sporadic medullary thyroid carcinoma were included; 47.2% and 39.2% had confirmed central and lateral lymph node metastases, respectively. Univariate and multivariate analyses identified 2 independent factors associated with lateral lymph node metastases: positive central lymph node metastases (odds ratio = 9.764, 95% confidence interval: 2.610-36.523; p = 0.001) and positive lateral lymph nodes on ultrasonography (odds ratio = 101.747, 95% confidence interval: 14.666-705.869; p < 0.001).

CONCLUSION

Medullary thyroid carcinoma is a rare endocrine malignancy. Lymph node metastases are common in patients with sporadic medullary thyroid carcinoma. Prophylactic lateral neck dissection is recommended for patients who exhibit positive central lymph node metastases and/or positive lateral lymph nodes on ultrasonography.

Anlotinib for the Treatment of Patients with Locally Advanced or Metastatic Medullary Thyroid Cancer

BACKGROUND

The prognosis of advanced or metastatic medullary thyroid carcinoma (MTC) is poor, and there are few therapeutic options. Anlotinib has previously shown promising antitumor activity on MTC in preclinical models and a Phase I study. This Phase II clinical trial was devised to confirm the antitumor activity of anlotinib in patients with advanced or metastatic MTC.

METHODS

Patients with unresectable locally advanced or metastatic MTC received once daily oral anlotinib 12 mg, two weeks on/one week off, until disease progression, death, unacceptable toxicity, or withdrawal of consent for any reason. The dose was adjusted on the basis of observed toxicity. The primary endpoint was progression-free survival (PFS).

RESULTS

Fifty-eight patients received anlotinib treatment. The primary endpoint PFS has not yet been reached at the time of analysis. On the basis of investigator assessments, 56.9% of patients experienced a partial response. PFS rate at 48 weeks was 85.5%. Forty-five patients had a ≥50% decrease in serum calcitonin concentration from baseline. The most common adverse events were hand-foot syndrome, hypertriglyceridemia, cholesterol elevation, fatigue, and proteinuria.

CONCLUSIONS

Anlotinib demonstrated a durable antitumor activity with a manageable adverse event profile in locally advanced or metastatic MTC.

Ultrasound-guided laser ablation for local control of neck recurrences of medullary thyroid cancer. A feasibility study

BACKGROUND

Surgery is the standard treatment for cervical metastases of medullary thyroid cancer (MTC) diagnosed after initial surgical treatment. Repeated neck dissections, however, carry an elevated risk of complications, have an adverse impact on the quality of life, and sometimes do not achieve cure of the disease Clinical case: In a patient who had undergone two cervical neck dissections complicated by accessory nerve injury, an US-guided laser ablation (LA) of a lymph node metastasis of MTC was performed. LA was performed with two treatments during a five month period. The procedure was carried out with one optical fiber and an energy delivery of 3300 and 360 Joules. Treatments were well tolerated and resulted in complete structural and biochemical cure during a 12 month follow-up. No major complication was registered.

CONCLUSIONS

LA is a promising tool for the management of relapsing cervical metastases that are localized in non- critical areas and are characterized by low progression rate. Advantages of LA are the outpatient setting, the absence of general anesthesia, the tolerability and the safety of the procedure. Thus, LA may be considered as an alternative approach to surgery or active surveillance for the management of local recurrences of MTC in selected patients.

Molecular signatures of medullary thyroid carcinoma by matrix-assisted laser desorption/ionisation mass spectrometry imaging

The main aim of the study was to assess the feasibility of matrix-assisted laser desorption/ionisation mass spectrometry imaging (MALDI-MSI) in the pathological investigation of Medullary Thyroid Carcinoma (MTC). Formalin-fixed paraffin-embedded (FFPE) samples from seven MTC patients were analysed by MALDI-MSI in order to detect proteomic alterations within tumour lesions and to define the molecular profiles of specific findings, such as amyloid deposition and C cell hyperplasia (CCH). nLC-ESI MS/MS was employed for the identification of amyloid components and to select alternative proteomic markers of MTC pathogenesis. Results highlighted the potential of MALDI-MSI to confirm the classic immunohistochemical methods employed for the diagnosis of MTC, with good sensitivity and specificity. Intratumoural amyloid components were also detected and identified, and were characterised by calcitonin, apolipoprotein E, apolipoprotein IV, and vitronectin. The tryptic peptide profiles representative of MTC and CCH were distinctly different, with four alternative markers for MTC being detected; K1C18, and three histones (H2A, H3C, and H4). Finally, a further 115 proteins were identified through the nLC-ESI-MS/MS analysis alone, with moesin, veriscan, and lumican being selected due to their potential involvement in MTC pathogenesis. This approach represents a complimentary strategy that could be employed to detect new proteomic markers of MTC. STATEMENT OF SIGNIFICANCE: Medullary thyroid carcinoma (MTC) is a rare endocrine malignancy that originates from the parafollicular C-cells of the thyroid. The diagnosis is typically established using a combination of fine-needle aspiration biopsy (FNAB) of a suspicious nodule along with the demonstrable elevation of serum biomarkers, such as calcitonin and carcinoembryonic antigen (CEA). Unfortunately, this combination is often associated with a high degree of false-positive results and this can lead to misdiagnosis and avoidable total thyroidectomy. The current study presents the potential role of MALDI-MSI in the search for new proteomic markers of MTC with diagnostic and prognostic significance. MALDI-MSI was capable of detecting the classic immunohistochemical markers employed for the diagnosis of MTC, with good sensitivity and specificity. Furthermore, the complementary combination of MALDI-MSI and nLC-ESI-MS/MS analysis, using a single tissue section, enabled further potential markers to be identified and their spatial localisation visualised within tumoural regions. Such findings could be a valuable starting point for further studies focused on confirming the data presented here using thyroid FNABs, with the final objective being to provide complimentary assistance for the detection of MTC during the pre-operative phase.

Analysis of risk factors for cervical lymph node metastases in patients with sporadic medullary thyroid carcinoma

Objective

Medullary thyroid carcinoma (MTC) is classified as either sporadic or inherited. This study was performed to analyze the risk factors for cervical lymph node metastases and predict the indication for prophylactic lateral neck dissection in patients with sporadic MTC.

Methods

Sixty-five patients with sporadic MTC were retrospectively reviewed. Univariate analysis with the chi-square test and multiple logistic regression analysis were applied to identify the clinicopathological features (sex, age, tumor size, number of tumor foci, capsule or vascular invasion, and others) associated with cervical lymph node metastases.

Results

The metastasis rates in the central and lateral compartments were 46.2% (30/65) and 40.0% (26/65), respectively. The incidence of cervical lymph node metastases was significantly higher in patients with a tumor size of >1 cm, tumor multifocality, and thyroid capsule invasion. Only thyroid capsule invasion was an independent predictive factor for central compartment metastases and lateral neck metastases. The possibility of central compartment metastases was significantly higher when the preoperative serum carcinoembryonic antigen concentration was >30 ng/mL (60.0% vs. 34.3%).

Conclusions

MTC is associated with a high incidence of cervical lymph node metastases. Prophylactic lateral node dissection is necessary in patients with thyroid capsule invasion or a high serum carcinoembryonic antigen concentration.