Surgical management of well-differentiated thyroid cancer: state of the art

MFAP2 is a Potential Diagnostic and Prognostic Biomarker That Correlates with the Progression of Papillary Thyroid Cancer

Background

Microfibril-associated protein 2 (MFAP2) is a protein coding gene that exerts important phenotypic effects on cell motility, and increasing research has indicated that MFAP2 was correlated with many cancers. However, the functional and potential clinical role of MFAP2 in papillary thyroid cancer (PTC) has not yet been verified.

Materials and Methods

We performed whole transcriptome sequencing on 78 paired PTC tissues and corresponding adjacent normal tissues and found that MFAP2 was highly expressed in PTC tissues. Then, we analyzed the expression of MFAP2 and its relation with the clinicopathological features of PTC in The Cancer Genome Atlas (TCGA) PTC genomic dataset. We detected MFAP2 expression in 40 paired PTC tissues and corresponding adjacent normal tissues through RT-qPCR (real time-quantitative polymerase chain reaction) to validate the sequencing data and TCGA cohort. Cell functional assays were performed to elucidate the function of MFAP2 in PTC cells, Western blot assay was performed to explore the correlation between MFAP2 and EMT (epithelial-mesenchymal transition)-related proteins.

Results

Statistical analysis showed that MFAP2 was obviously upregulated in PTC tissues compared to matched normal tissues, and the expression levels of MFAP2 in PTC tissues were strongly related with lymph node metastasis (p=0.016). The results of RT-qPCR of our own tissue specimens showed the same conclusions as that in TCGA dataset. The results of functional assays in PTC cell lines showed that MFAP2 could promote proliferation, colony formation, migration and invasion abilities and decrease the apoptotic rate in PTC cells. Western Blot assay showed that MFAP2 could regulate the expression of EMT-related proteins.

Conclusion

MFAP2 increases the proliferation, motility and decreases the apoptosis of PTC cells, and might be a potential therapeutic target for papillary thyroid cancer.

Selective Neck Dissection Guided by a Radioactive I125 Seed for Papillary Thyroid Carcinoma Recurrence

Lymph nodes are the most common place of recurrence of papillary thyroid cancer, and surgery can be considered a therapeutic option. The risks of surgery increase with every intervention. We present 3 cases of cervical non palpable thyroid cancer recurrence managed with I125 seed radioguided cervical dissection from 2017 to 2019. Two of the cases had already a thyroidectomy and central compartment lymphadenectomy performed. The seed was placed guided by US on the lesion and its position was confirmed afterwards. The target was successfully localized in 100% of cases. There was no post surgery complications. There was no evidence of recurrence with a mean follow up of 15 months. Radioguided surgery using I125 seed it is a save technique and it offers a precise localization of the non palpable thyroid cancer recurrence.

LINC00511 influences cellular proliferation through cyclin-dependent kinases in papillary thyroid carcinoma

Background: Proverbially, the incidence rate of papillary thyroid carcinoma (PTC) has increased year by year. Many long noncoding RNAs (lncRNAs) have been discovered having a relationship with tumor genesis tightly recently. Thanks to the previous researches, we found long intergenic noncoding RNA 00511 (LINC00511) is overexpressed and acts as an oncogene in non-small-cell lung cancer and breast cancer. However, the biological role and function of LINC00511 are still unclear in PTC. Methods: We got the expression of LINC00511 in PTC tissues and matched adjacent tissues, as well the cell lines (B-CPAP, KTC-1, and KTC-1) by way of quantitative real-time polymerase chain reaction (qRT-PCR). In vitro, we knocked down the LINC00511 with small interfering RNA in PTC cell lines and demonstrated the function of LINC00511 by Cell Counting Kit-8, cell colony formation, Transwell migration, Transwell invasion, apoptosis assays, and cell cycle assays. Then, we discovered several downstream proteins of LINC00511 using Western blotting. Results: We proved that LINC00511's expression in PTC tissues and cell lines is higher than the control. LINC00511 promoted cellular proliferation, migration, invasion, G1/S transition and reduced apoptosis in vitro experiment. Knocked-down of LINC00511 resulted in the reduction of histone methyltransferase enhancer of zeste homolog 2 (EZH2), cyclin-dependent kinase 2 (CDK2) and cyclin-dependent kinase 4 (CDK4). Conclusions: Our results certified the role and function of LINC00511 in PTC, and it could become a novel tumor therapeutic target.

The value of the computer-aided diagnosis system for thyroid lesions based on computed tomography images

Background

Thyroid nodules are commonly found at palpation amounting to 4-7% of the asymptomatic population and 50% of the cases are found at autopsy. Only a small proportion of thyroid nodules are malignant. The major challenge is the differential diagnosis of benign or malignant thyroid nodules, so we aim to develop the computer-assisted diagnostic method based on computed tomography (CT) images for thyroid lesions.

Methods

In this study, we retrospectively collected 52 benign and 46 malignant thyroid nodules from 90 patients in CT examinations, together with the pathologist findings and radiology diagnosis. The first-order statistic and gray-level co-occurrence matrix features were extracted from thyroid computed tomography images. These texture features were used to assess the malignancy risk of the thyroid nodules. Several classification algorithms, including support vector machine, linear discriminant analysis, random forest, and bootstrap aggregating, were applied in the prediction. Leave-one-out cross-validation was used to evaluate the performance of thyroid cancer recognition.

Results

In thyroid cancer identification based on a computed tomography image, we found the system using 17 texture features and support vector machine performed well. The accuracy, area under the receiver operating characteristic curve, sensitivity, specificity, positive predictive value, and negative predictive value, were 0.8673, 0.9105, 0.9130, 0.8269, 0.8235 and 0.9146, respectively.

Conclusions

The proposed computer-aided diagnosis system provides a good assessment of the malignancy-risk of the thyroid nodules, which may help radiologists to improve the accuracy and efficiency of thyroid diagnosis.

Dynamic prediction of the risk of recurrence in patients over 60 years of age with differentiated thyroid carcinoma

OBJECTIVE

The reclassification of the risk according to the response to the initial treatment makes the treatment of differentiated thyroid cancer (DTC) vary in each individual. As the influence of age on this diagnostic strategy is unknown, we have decided to assess it in adults who are over 60 years of age.

SUBJECTS AND METHODS

Ninety patients with DTC above 60 years old were enrolled, with total thyroidectomy plus radioiodine ablation, negative anti-thyroglobulin antibodies, follow-up ≥ 2 years and with clinical and pathological information to classify the risk of recurrence according to ATA (American Thyroid Association) and reclassify based on the response to initial therapy according to MSKCC (Memorial Sloan Kettering Cancer Center). The structural persistence at the end of the follow-up was the gold standard of our analysis.

RESULTS

The structural persistence in ATA low, intermediate and high risk categories was 0, 38, and 100%, respectively. In the intermediate group, none of those with an excellent response to the initial treatment showed structural persistence, whereas 39% of those with an incomplete/indeterminate response showed structural persistence (p < 0.01).

CONCLUSIONS

The re-stratification according to the response to the initial treatment in patients over 60 years of age with an ATA intermediate risk of recurrence allowed for the distinction of disease-free patients at the end of the follow-up from those with structural persistence and a worse clinical progression.

Prediction of central lymph node metastasis in 392 patients with cervical lymph node-negative papillary thyroid carcinoma in Eastern China

Central lymph node metastasis (CLNM) is common in papillary thyroid microcarcinoma (PTMC). The aim of the present study was to investigate the risk factors associated with CLNM in clinical lateral cervical lymph node-negative (cN0) PTMC in Eastern China. A total of 392 patients with confirmed PTMC by histological examination who underwent thyroidectomy and central neck lymph node dissection (CND) between May 2011 and October 2012 at the First Affiliated Hospital of Wenzhou Medical University (Wenzhou, China) were enrolled. The clinicopathological and ultrasonographic data from the patients were analyzed retrospectively. A scoring system was developed on the basis of independent predictive factors for CLNM. Male gender, age <45 years, maximum tumor diameter >5 mm, lower lobe location, multifocal carcinoma with total tumor diameter >10 mm and extracapsular spread were independent predictive factors for CLNM according to logistic regression analysis. The clinicopathological score was statistically significant, with an index point ≥2 indicating CLNM with 86.2% sensitivity and 70.4% specificity. The findings of the present study indicate that CND may be recommended to be routinely performed when the clinicopathological index point ≥2.

BRAF mutation in papillary thyroid cancer and its value in tailoring initial treatment: a systematic review and meta-analysis

Clinicians have long sought to characterize biological markers of neoplasia as objective indicators of tumor presence, pathogenicity, and prognosis. Armed with data that correlate biomarker activity with disease presence and progression, clinicians can develop treatment strategies that address risks of disease recurrence or persistence and progression. The B-type Raf kinase (BRAF V600E) mutation in exon 15 of the BRAF gene has been noted to be a putative prognostic marker of the most prevalent form of thyroid cancer, papillary thyroid cancer (PTC)--a tumor type with high proclivity for recurrence or persistence. There has been a remarkable interest in determining the association of BRAF mutation with PTC recurrence or persistence. Using many new studies that have been published recently, we performed a meta-analysis to investigate correlations of BRAF mutation status with PTC prognosis, focusing on the recurrence or persistence of the disease after initial treatment. The study was based on published studies included in the PubMed and Embase databases addressing the BRAF mutation and the frequency of recurrence of PTC. We selected studies with data that enabled measurement of the risk ratio for recurrent disease. We also analyzed the factors that are classically known to be associated with recurrence. These factors included lymph node metastasis, extrathyroidal extension, distant metastasis, and American Joint Committee on Cancer (AJCC) stages III/IV. We used 14 articles that included an analysis of these factors as well as PTC recurrence data, with a total of 2470 patients from 9 different countries. The overall prevalence of the BRAF mutation was 45%. The risk ratios in BRAF mutation-positive patients were 1.93 (95% confidence interval [CI], 1.61-2.32; Z = 7.01; p < 0.00001) for PTC recurrence, 1.32 (95% CI, 1.20-1.45; Z = 5.73; p < 0.00001) for lymph node metastasis, 1.71 (95% CI, 1.50-1.94; Z = 8.09; p < 0.00001) for extrathyroidal extension, 0.95 (95% CI, 0.63-1.44; Z = 0.23; p = 0.82) for distant metastasis, and 1.70 (95% CI, 1.45-1.99; Z = 6.46; p < 0.00001) for advanced stage AJCC III/IV. Thus, in this meta-analysis, the BRAF mutation in PTC was significantly associated with PTC recurrence, lymph node metastasis, extrathyroidal extension, and advanced stage AJCC III/IV. Patients with PTC harboring mutated BRAF are likely to demonstrate factors that are associated with an increased risk for recurrence of the disease, offering new prospects for optimizing and tailoring initial treatment strategies to prevent recurrence.

Diagnostic adequacy of surgeon-performed ultrasound-guided fine needle aspiration biopsy of thyroid nodules

BACKGROUND

Surgeon-performed ultrasonography (US) of thyroid nodules might serve as a potential therapeutic guide to designate accurate surgical or clinical intervention.

OBJECTIVE

To evaluate the diagnostic adequacy of surgeon-performed ultrasonography guided fine needle aspiration biopsy (FNAB) of thyroid nodules, the factors responsible for diagnostic adequacy and the impact of surgeon-performed US on treatment approach.

METHODS

Retrospective review of a single surgeon performed 621 US-guided FNABs without on-site cytological specimen assessment. Outside US findings were compared to the surgeon-performed US. Measured variables and outcomes for the study included diagnostic adequacy rates and the effects of detected differences between US reports on treatment variability.

RESULTS

Diagnostic adequacy rate of surgeon-performed US-guided FNAB was determined to be 94.52% without on-site specimen evaluation by cytologist. Non-diagnostic specimens occurred in 34 of 621 (5.48%) nodules. The differences detected between the outside US and surgeon-performed US altered invasive treatment algorithm in 30 (5.47%) patients. FNAB was avoided for 15 (2.7%) patients. Total thyroidectomy became the preferred surgical option in 15 (2.7%) patients after the discovery of additional nodules in the contralateral lobe.

CONCLUSION

Surgeon-performed US offers clear clinical benefits in terms of diagnostic yield of FNAB with providing valuable additional data that might alter surgical treatment approach.

Histological patterns of locoregional recurrence in Hürthle cell carcinoma of the thyroid gland

BACKGROUND

Hürthle cell carcinoma (HCC) is regarded as an aggressive variant of follicular thyroid carcinoma based in part on its propensity to metastasize regionally and recur locally. The current treatment recommendation of formal regional lymph node dissection is largely based on the presumption of lymphatic dissemination to cervical lymph nodes as the main mechanism of regional spread. The purpose of this study was to better define the distribution of locoregional recurrence in HCC, and specifically to differentiate soft-tissue implants from true nodal metastases.

METHODS

The surgical pathology files of The Johns Hopkins Hospital were searched for cases of HCC with locoregional recurrences. The slides were reviewed to assess the histologic patterns of tumor spread, including the presence or absence of lymph node metastasis. Elastic staining was used to confirm vessel invasion.

RESULTS

Twenty-four cases from 19 patients were identified. Thirteen were men, and the patients ranged in age from 35 to 83 years (mean 66). All had total or near-total thyroidectomies, and 16 received postoperative radioactive iodine. The time from primary diagnosis to first recurrence ranged from 0 to 12 years (mean 5 years). The locoregional disease involved the lateral neck (n=16), central neck (n=18), and larynx/trachea (n=4). In all 24 cases, the dominant tumor nodule was present as a rounded nodule of carcinoma within the soft tissues and unassociated with lymphoid tissue. Of 22 cases evaluated by elastic staining, 13 had tumor nodules within veins. True lymph node metastases were present in only six (25%) cases, and in all but one case, the lymph node metastases were <0.5 cm.

CONCLUSIONS

When HCC spreads in the neck, it usually does so as soft-tissue implants likely resulting from spread within venous channels. True lymph node metastases are not a major source of nodular recurrences in the neck. Resolving the pattern of tumor spread could help guide and refine the management of locoregional recurrence for patients with HCC.

Successful surgical treatment of advanced follicular thyroid carcinoma with tumor thrombus infiltrating the superior vena cava: report of a case

We report a case of advanced follicular thyroid carcinoma with massive involvement of the great veins of the cervix and mediastinum, and extensive tumor thrombus growing intraluminally into the superior vena cava. The patient, a 70-year-old Japanese woman, was treated successfully by a cooperative surgical team of endocrine and cardiovascular surgeons. Total thyroidectomy with thrombectomy was performed via a minimum phlebotomy in the right brachiocephalic vein, sacrificing only the right internal jugular vein, achieving complete primary tumor resection. She recovered quickly without any complications, and received (131)I radioisotope ablation for her multiple lung metastases. At the time of writing, more than 12 months after surgery, she was well. These treatments thus achieved progression-free survival without impairing her quality of life. Following the case report, we discuss the surgical indications for locally advanced thyroid carcinoma involving the great veins of the mediastinum by reviewing previous reports.

Advances in surgical therapy for thyroid cancer

Thyroid cancer is the most common malignancy of the endocrine system and its incidence has dramatically increased over the past three decades. Well-differentiated thyroid cancers (DTCs) are the main focus of this article, as they represent >90% of thyroid malignancies. This Review provides an overview of the controversies surrounding the optimal choice of surgery and extent of resection for patients with low-risk DTC or with papillary thyroid microcarcinoma, and the role of prophylactic central lymph node dissection. This Review also outlines the current surgical management of DTC and presents updated results for these techniques, along with important advances and current dilemmas in surgical approaches to treatment of these cancers. For example, endoscopic and robotic thyroidectomy are the two most recent innovations to present technical and other challenges to the endocrine surgeon; in addition, the risks as well as the advantages of same-day thyroid surgery, which has gained some acceptance, are detailed. Arguments for and against each approach are presented, along with supporting evidence. The authors' personal opinions are also provided for each topic.