Non-FDG-avid primary papillary thyroid carcinoma may not differ from FDG-avid papillary thyroid carcinoma

Metastatic Papillary Thyroid Cancer Mimicking Hypopharyngeal Carcinoma

ABSTRACT

Papillary thyroid cancer (PTC) metastasizing to the hypopharynx is extremely rare. Here, we describe FDG PET/CT findings of lesions in the posterior hypopharyngeal wall and left parapharyngeal space in a 58-year-old man who complained of blood in the sputum. The patient had a history of postoperative PTC. Therefore, hypopharyngeal carcinoma with lymph node metastasis was suspected. However, metastasis of PTC was pathologically confirmed after surgery. Hypopharyngeal metastasis of PTC is rare, which should be differentiated from hypopharyngeal carcinoma with metastasis.

[18F]FDG Uptake and Expression of Immunohistochemical Markers Related to Glycolysis, Hypoxia, and Proliferation in Indeterminate Thyroid Nodules

PURPOSE

The current study explored the association between 2-[¹⁸F]fluoro-2-deoxy-D-glucose ([¹⁸F]FDG) uptake and the quantitative expression of immunohistochemical markers related to glucose metabolism, hypoxia, and cell proliferation in benign and malignant thyroid nodules of indeterminate cytology.

PROCEDURES

Using a case-control design, 24 patients were selected from participants of a randomized controlled multicenter trial (NCT02208544) in which [¹⁸F]FDG-PET/CT and thyroid surgery were performed for Bethesda III and IV nodules. Three equally sized groups of [¹⁸F]FDG-positive malignant, [¹⁸F]FDG-positive benign, and [¹⁸F]FDG-negative benign nodules were included. Immunohistochemical staining was performed for glucose transporters (GLUT) 1, 3, and 4; hexokinases (HK) 1 and 2; hypoxia-inducible factor-1 alpha (HIF1α; monocarboxylate transporter 4 (MCT4); carbonic anhydrase IX (CA-IX); vascular endothelial growth factor (VEGF); sodium-iodide symporter (NIS); and Ki-67. Marker expression was scored using an immunoreactive score. Unsupervised cluster analysis was performed. The immunoreactive score was correlated to the maximum and peak standardized uptake values (SUV_max, SUV_peak) and SUV_max ratio (SUV_max of nodule/background SUV_max of contralateral, normal thyroid) of the [¹⁸F]FDG-PET/CT using the Spearman's rank correlation coefficient and compared between the three groups using Kruskal-Wallis tests.

RESULTS

The expression of GLUT1, GLUT3, HK2, and MCT4 was strongly positively correlated with the SUV_max, SUV_peak, and SUV_max ratio. The expression of GLUT1 (p = 0.009), HK2 (p = 0.02), MCT4 (p = 0.01), and VEGF (p = 0.007) was statistically significantly different between [¹⁸F]FDG-positive benign nodules, [¹⁸F]FDG-positive thyroid carcinomas, and [¹⁸F]FDG-negative benign nodules. In both [¹⁸F]FDG-positive benign nodules and [¹⁸F]FDG-positive thyroid carcinomas, the expression of GLUT1, HK2, and MCT4 was increased as compared to [¹⁸F]FDG-negative benign nodules. VEGF expression was higher in [¹⁸F]FDG-positive thyroid carcinomas as compared to [¹⁸F]FDG-negative and [¹⁸F]FDG-positive benign nodules.

CONCLUSIONS

Our results suggest that [¹⁸F]FDG-positive benign thyroid nodules undergo changes in protein expression similar to those in thyroid carcinomas. To expand the understanding of the metabolic changes in benign and malignant thyroid nodules, further research is required, including correlation with underlying genetic alterations.

Multiparametric Photoacoustic Analysis of Human Thyroid Cancers In Vivo

Thyroid cancer is one of the most common cancers, with a global increase in incidence rate for both genders. Ultrasound-guided fine-needle aspiration is the current gold standard to diagnose thyroid cancers, but the results are inaccurate, leading to repeated biopsies and unnecessary surgeries. To reduce the number of unnecessary biopsies, we explored the use of multiparametric photoacoustic (PA) analysis in combination with the American Thyroid Association (ATA) Guideline (ATAP). In this study, we performed in vivo multispectral PA imaging on thyroid nodules from 52 patients, comprising 23 papillary thyroid cancer (PTC) and 29 benign cases. From the multispectral PA data, we calculated hemoglobin oxygen saturation level in the nodule area, then classified the PTC and benign nodules with multiparametric analysis. Statistical analyses showed that this multiparametric analysis of multispectral PA responses could classify PTC nodules. Combining the photoacoustically indicated probability of PTC and the ATAP led to a new scoring method that achieved a sensitivity of 83% and a specificity of 93%. This study is the first multiparametric analysis of multispectral PA data of thyroid nodules with statistical significance. As a proof of concept, the results show that the proposed new ATAP scoring can help physicians examine thyroid nodules for fine-needle aspiration biopsy, thus reducing unnecessary biopsies.

Investigating 18F-FDG PET/CT Parameters as Prognostic Markers for Differentiated Thyroid Cancer: A Systematic Review

Aims: The aim of this study was to determine whether ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸F-FDG PET/CT) parameters might be prognostic markers for patients with differentiated thyroid carcinoma (DTC).

Methods: We searched for eligible articles in PubMed, EMBASE (Ovid), Cochrane Library, and ClinicalTrials.gov from inception to February 2021. We included studies addressing the association between ¹⁸F-FDG PET/CT parameters and clinical outcomes among patients with DTC. Quality assessment was performed using the Quality in Prognosis Studies (QUIPS) tool.

Results: A total of 25 studies including 2,954 patients (1,994 females, 67.5%) were included; 2,416 patients (81.8%) had papillary thyroid carcinoma (PTC), and the mean or median follow-up time ranged from 19.1 months to 17.1 years. Thirteen (52.0%) studies were assessed as “unclear” for the domain of study participation. The most common timing of PET/CT scans was after thyroidectomy (in 20 of 25 studies, 80%), especially in patients with an elevated thyroglobulin (Tg) and a negative radioiodine whole-body scan (WBS). The most common PET parameter was FDG uptake. Twelve of 17 (70.6%) and 12 of 12 (100%) studies showed an association between PET/CT parameters and disease progression and survival in patients with DTC, respectively.

Conclusion:¹⁸F-FDG PET/CT parameters alone or combined with other variables can serve as prognostic markers to identify DTC patients with poor outcomes, especially in the setting of an elevated Tg and a negative WBS. Future research is needed to confirm these findings and to examine the prognostic value of PET/CT parameters for DTC patients, considering the heterogeneity in PET/CT parameters, unclear information of patients, and PET/CT-adapted treatment modifications.

Hif-1α Inhibitors Could Successfully Inhibit the Progression of Differentiated Thyroid Cancer in Vitro

Hypoxia-inducible factor (HIF)-1α plays an important role in cancer progression. In various cancers, including thyroid cancer, overexpression of HIF-1α is related to poor prognosis or treatment response. However, few studies have investigated the role of HIF-1α inhibition in thyroid cancer progression. We evaluated the utility of the HIF-1α inhibitor IDF-11774 in vitro utilizing two thyroid cancer cell lines, K1 and BCPAP. Both cell lines were tested to elucidate the effects of IDF-11774 on cell proliferation and migration using soft agar and invasion assays. Here, we found that a reduction of HIF-1α expression in BCPAP cells was observed after treatment with IDF-11774 in a dose-dependent manner. Moreover, cell proliferation, migration, and anchorage-independent growth were effectively inhibited by IDF-11774 in BCPAP cells but not in K1 cells. Additionally, invasion of BCPAP but not K1 cells was controlled with IDF-11774 in a dose-dependent manner. Our findings suggest that promoting the degradation of HIF-1α could be a strategy to manage progression and that HIF-1α inhibitors are potent drugs for thyroid cancer treatment.

Comparison of Natural Course between Thyroid Cancer Nodules and Thyroid Benign Nodules

BACKGROUND

The natural course of thyroid cancer nodules and benign nodules is different. This study was to compare the changes in size between thyroid cancer nodules and thyroid benign nodules. The risk factors associated with the changes of thyroid cancer nodules were assessed.

METHODS

This study contains retrospective observational and prospective analysis. A total of 113 patients with 120 nodules were recruited in the cancer group, and 116 patients with 119 nodules were enrolled in the benign group. Thyroid ultrasonography was performed at least two times at more than 1-year interval.

RESULTS

The mean follow-up durations were 29.5±18.8 months (cancer group) and 31.9±15.8 months (benign group) (P=0.32). The maximum diameter change in length was 0.36±0.97 mm/year in the cancer group and -0.04±0.77 mm/year in the benign group (P<0.01). The volume was significantly increased in the cancer group compared with the benign group (0.06±0.18 mL/year vs. 0.004±0.05 mL/year, respectively, P<0.01; 26.9%±57.9%/year vs. 1.7%±26.0%/year, P<0.01). Initial maximum diameter (β=0.02, P<0.01) and initial volume (β=0.13, P<0.01) were significantly associated with volume change (mL)/year. Initial maximum standardized uptake value did not predict the nodule growth.

CONCLUSION

It is suggested that thyroid cancer nodules progress rapidly compared with benign nodules. Initial size and volume of nodule were independent risk factors for cancer nodule growth.

Roles of GLUT-1 and HK-II expression in the biological behavior of head and neck cancer

The Warburg effect plays an important role in the proliferation and invasion of malignant tumors. Glucose transporter 1 and hexokinase II are two key energy transporters involved in mediating the Warburg effect. This review will analyze the mechanisms of these two markers in their effects on the biological behavior of head and neck cancer.

Clinicopathological characteristics including BRAF V600E mutation status and PET/CT findings in papillary thyroid carcinoma

OBJECTIVE

We assessed the associations between FDG uptake in primary papillary thyroid carcinomas (PTCs) and clinicopathological features, including the BRAF V600E mutation, using quantitative and qualitative analyses of preoperative PET/CT data.

DESIGN AND PATIENTS

This was a retrospective review of 106 patients with PTC who underwent PET/CT scans between February 2009 and January 2011 before undergoing total thyroidectomy. Data collected from surgical specimens were compared with FDG uptake in the primary tumour using quantitative and qualitative analyses of preoperative PET/CT data. Clinicopathological data included the primary tumour size, subtype, capsular invasion, extrathyroid extension, multifocality, BRAF V600E mutation status, lymph node metastasis and distant metastasis.

RESULTS

The SUVmax of the primary tumour was significantly higher in patients with a primary tumour >1 cm, extrathyroid extension or the BRAF V600E mutation than in patients without these features (P<.001, .049 and <.001). Univariate analyses showed that primary tumour size, extrathyroid extension and BRAF V600E mutation status were associated with the SUVmax of the PTC. Multivariate analysis indicated that primary tumour size and the BRAF V600E mutation were associated with the SUVmax of the PTC. In a visual assessment, the primary tumour size was larger in FDG-avid than in non-FDG-avid PTCs (P<.001). There was no significant difference in the presence of multifocality, thyroid capsular invasion, extrathyroid extension, BRAF V600E mutation, lymph node metastasis or distant metastasis between FDG-avid and non-FDG-avid PTCs.

CONCLUSIONS

Primary tumour size and the BRAF V600E mutation are significant factors associated with the SUVmax on preoperative PET/CT in patients with PTC.

Multicompartment metabolism in papillary thyroid cancer

OBJECTIVES/HYPOTHESIS

In many cancers, varying regions within the tumor are often phenotypically heterogeneous, including their metabolic phenotype. Further, tumor regions can be metabolically compartmentalized, with metabolites transferred between compartments. When present, this metabolic coupling can promote aggressive behavior. Tumor metabolism in papillary thyroid cancer (PTC) is poorly characterized.

STUDY DESIGN

Immunohistochemical staining of tissue samples.

METHODS

Papillary thyroid cancer specimens from 46 patients with (n = 19) and without advanced disease (n = 27) were compared to noncancerous thyroid tissue (NCT) and benign thyroid specimens (n = 6 follicular adenoma [FA] and n = 5 nodular goiter [NG]). Advanced disease was defined as the presence of lateral neck lymphadenopathy. Immunohistochemistry was performed for translocase of outer mitochondrial membrane 20 (TOMM20), a marker of oxidative phosphorylation, and monocarboxylate transporter 4 (MCT4), a marker of glycolysis.

RESULTS

Papillary thyroid cancer and FA thyrocytes had high staining for TOMM20 compared to NCT and nodular goiter (NG) (P < 0.01). High MCT4 staining in fibroblasts was more common in PTC with advanced disease than in any other tissue type studied (P < 0.01). High MCT4 staining was found in all 19 cases of PTC with advanced disease, in 11 of 19 samples with low-stage disease, in one of five samples of FA, in one of 34 NCT, and in 0 of six NG samples. Low fibroblast MCT4 staining in PTC correlated with the absence of clinical adenopathy (P = 0.028); the absence of extrathyroidal extension (P = 0.004); low American Thyroid Association risk (P = 0.001); low AGES (age, grade, extent, size) score (P = 0.004); and low age, metastasis, extent of disease, size risk (P = 0.002).

CONCLUSION

This study suggests that multiple metabolic compartments exist in PTC, and low fibroblast MCT4 may be a biomarker of indolent disease.

LEVEL OF EVIDENCE

N/A. Laryngoscope, 126:2410-2418, 2016.

Association Between (18)F-FDG Avidity and the BRAF Mutation in Papillary Thyroid Carcinoma

PURPOSE

The BRAF mutation, a potential prognostic factor in papillary thyroid carcinoma (PTC), is associated with a high expression of the glucose transporter gene. We investigated which clinicopathologic factors, including BRAF mutation status, influence (18)F-fluoro-2-deoxyglucose ((18)F-FDG) avidity.

METHODS

We retrospectively reviewed 55 patients who underwent BRAF analysis from biopsy-confirmed PTC and (18)F-FDG positron emission tomography/computed tomography within 6 months before undergoing thyroid surgery from September 2008 to August 2014. Tumors were considered to be (18)F-FDG avid if the uptake was greater than that of the liver. (18)F-FDG uptake of PTCs was also analyzed semiquantitatively using SUVmax. The association between (18)F-FDG avidity and clinicopathologic variables (age, tumor size, perithyroidal extension, cervical lymph node status, and BRAF mutation status) was investigated.

RESULTS

Twenty-nine (52.7 %) of 55 patients had (18)F-FDG-avid PTCs. PTCs with the BRAF mutation showed higher (18)F-FDG avidity (24/38, 63.2 %) than those without (5/17, 29.4 %). The BRAF mutation (p = 0.025) and tumor size (p = 0.003) were significantly associated with (18)F-FDG avidity in univariate analysis, and the BRAF mutation status remained significant after adjusting for tumor size in multivariate analysis (p = 0.015). In the subgroup of tumor size ≥ 1 cm, the BRAF mutation was the only factor significantly associated with (18)F-FDG avidity (p = 0.021). The mean SUVmax of PTCs with the BRAF mutation was significantly higher than that of those without (4.89 ± 6.12 vs. 1.96 ± 1.10, p = 0.039).

CONCLUSIONS

The BRAF mutation must be one of the most important factors influencing (18)F-FDG avidity in PTCs, especially in those with a tumor size ≥ 1 cm.

Correlation of BRAFV600E Mutation and Glucose Metabolism in Thyroid Cancer Patients: An ¹⁸F-FDG PET Study

There is significant interest in a better understanding of the genetic underpinnings of the increased glucose metabolic rates of cancer cells. Thyroid cancer demonstrates a broad variability of (18)F-FDG uptake as well as several well-characterized oncogenic mutations. In this study, we evaluated the differences in glucose metabolism of the BRAF(V600E) mutation versus BRAF wild-type (BRAF-WT) in patients with metastatic differentiated thyroid cancer (DTC) and poorly differentiated thyroid cancer (PDTC).

METHODS

Forty-eight DTC and 34 PDTC patients who underwent (18)F-FDG PET/CT for tumor staging were identified from a database search. All patients were tested for the BRAF(V600E) mutation and assigned to 1 of 2 groups: BRAF(V600E) mutated and BRAF-WT. (18)F-FDG uptake of tumor tissue was quantified by maximum standardized uptake value (SUVmax) of the hottest malignant lesion in 6 prespecified body regions (thyroid bed, lymph nodes, lung, bone, soft tissue, and other). When there were multiple lesions in 1 of the prespecified body regions, only the 1 with the highest (18)F-FDG uptake was analyzed.

RESULTS

In the DTC cohort, 24 tumors harbored a BRAF(V600E) mutation, whereas 24 tumors were BRAF-WT. (18)F-FDG uptake of BRAF(V600E)-positive lesions (median SUVmax, 6.3; n = 53) was significantly higher than that of BRAF-WT lesions (n = 39; median SUVmax, 4.7; P = 0.019). In the PDTC group, only 5 tumors were BRAF(V600E)-positive, and their (18)F-FDG uptake was not significantly different from the BRAF-WT tumors. There was also no significant difference between the SUVmax of all DTCs and PDTCs, regardless of BRAF mutational status (P = 0.90).

CONCLUSION

These data suggest that BRAF(V600E)-mutated DTCs are significantly more (18)F-FDG-avid than BRAF-WT tumors. The effect of BRAF(V600E) on tumor glucose metabolism in PDTC needs further study in larger groups of patients.

Recurrent differentiated thyroid cancer: towards personalized treatment based on evaluation of tumor characteristics with PET (THYROPET Study): study protocol of a multicenter observational cohort study

BACKGROUND

After initial treatment of differentiated thyroid carcinoma (DTC) patients are followed with thyroglobulin (Tg) measurements to detect recurrences. In case of elevated levels of Tg and negative neck ultrasonography, patients are treated 'blindly' with Iodine-131 (131I). However, in up to 50% of patients, the post-therapy scan reveals no 131I-targeting of tumor lesions. Such patients derive no benefit from the blind therapy but are exposed to its toxicity. Alternatively, iodine-124 (124I) Positron Emission Tomography/Computed Tomography (PET/CT) has become available to visualize DTC lesions and without toxicity. In addition to this, 18F-fluorodeoxyglucose (18F-FDG) PET/CT detects the recurrent DTC phenotype, which lost the capacity to accumulate iodine. Taken together, the combination of 124I and 18F-FDG PET/CT has potential to stratify patients for treatment with 131I.

METHODS/DESIGN

In a multicenter prospective observational cohort study the hypothesis that the combination of 124I and 18F-FDG PET/CT can avoid futile 131I treatments in patients planned for 'blind' therapy with 131I, is tested.One hundred patients planned for 131I undergo both 124I and 18F-FDG PET/CT after rhTSH stimulation. Independent of the outcome of the scans, all patients will subsequently receive, after thyroid hormone withdrawal, the 131I therapy. The post 131I therapeutic scintigraphy is compared with the outcome of the 124I and 18F-FDG PET/CT in order to evaluate the diagnostic value of the combined PET modalities.This study primary aims to reduce the number of futile 131I therapies. Secondary aims are the nationwide introduction of 124I PET/CT by a quality assurance and quality control (QA/QC) program, to correlate imaging outcome with histopathological features, to compare 124I PET/CT after rhTSH and after withdrawal of thyroid hormone, and to compare 124I and 131I dosimetry.

DISCUSSION

This study aims to evaluate the potential value of the combination of 124I and 18F-FDG PET/CT in the prevention of futile 131I therapies in patients with biochemically suspected recurrence of DTC. To our best knowledge no studies addressed this in a prospective cohort of patients. This is of great clinical importance as a futile 131I is a costly treatment associated with morbidity and therefore should be restricted to those likely to benefit from this treatment.

TRIAL REGISTRATION

Clinicaltrials.gov identifier: NCT01641679.