Incidental uptake of (18)F-fluorocholine (FCH) in the head or in the neck of patients with prostate cancer

Background

Positron emission tomography-computed tomography (PET/CT) with ¹⁸F-fluorocholine (FCH) is routinely performed in patients with prostate cancer. In this clinical context, foci of FCH uptake in the head or in the neck were considered as incidentalomas, except for those suggestive of multiple bone metastases.

Results

In 8 patients the incidental focus corresponded to a benign tumour. The standard of truth was histology in two cases, correlative imaging with MRI in four cases, ^99mTc-SestaMIBI scintigraphy, ultrasonography and biochemistry in one case and biochemistry including PTH assay in one case. The final diagnosis of benign tumours consisted in 3 pituitary adenomas, 2 meningiomas, 2 hyperfunctioning parathyroid glands and 1 thyroid adenoma.

Malignancy was proven histologically in 2 other patients: 1 papillary carcinoma of the thyroid and 1 cerebellar metastasis.

Conclusions

To the best of our knowledge, FCH uptake by pituitary adenomas or hyperfunctioning parathyroid glands has never been described previously. We thus discuss whether there might be a future indication for FCH PET/CT when one such tumour is already known or suspected: to detect a residual or recurrent pituitary adenoma after surgery, to guide surgery or radiotherapy of a meningioma or to localise a hyperfunctioning parathyroid gland. In these potential indications, comparative studies with reference PET tracers or with ^99mTc-sestaMIBI in case of hyperparathyroidism could be undertaken.

Oxidative Stress Correlates with More Aggressive Features in Thyroid Cancer

Oxidative stress (OS) can have an impact in the pathogenesis and in the progression of thyroid cancer. We investigated the levels of reactive oxygen species (ROS) in 50 malignant and benign thyroid lesions and 41 normal tissues, and correlated them with the thyroid differentiation score-TDS and the clinico-pathologic features. NOX4 expression, GPx activity and the genetic pattern of tumors were evaluated. In malignant and benign lesions, ROS generation and NOX4 protein expression were higher than in normal tissues. Follicular (FTCs) and anaplastic/poorly differentiated cancers had increased OS relative to papillary tumors (PTCs). Moreover, OS in FTCs was higher than in follicular adenomas. Mutated PTCs showed increased OS compared with non-mutated PTCs. In malignant tumors, OS was inversely correlated with TDS, and directly correlated with tumor stage and ATA risk. GPx activity was increased in tumors compared with normal tissues, and inversely correlated to OS. In conclusion, our data indicate that thyroid tumors are exposed to higher OS compared with normal tissues, while showing a compensative increased GPx activity. OS correlates with tumor aggressiveness and mutations in the MEK-ERK pathway in PTC. The inverse correlation between OS and TDS suggests that ROS may repress genes involved in thyroid differentiation.

Correlation between serum lead and thyroid diseases: papillary thyroid carcinoma, nodular goiter, and thyroid adenoma

Studies have showed that lead was associated with human health. However, the effects of lead on thyroid functions are inconsistent, and studies based on Chinese population are fragmentary. To evaluate the correlation between lead and thyroid functions of Chinese with different thyroid diseases, we conducted a hospital-based study. Ninety-six papillary thyroid carcinoma (PTC), 10 nodular goiter (NG), and 7 thyroid adenoma (TA) patients were recruited from the First Affiliated Hospital of Wenzhou Medical University, China. Serum triiodothyronine (T3), free triiodothyronine (FT3), free thyroxin (FT4), and thyroid stimulating hormone (TSH) were evaluated with chemiluminescent microparticle immunoassay. Serum lead was assessed with ICP-MASS. Partial correlation was used to explore the correlations of serum lead and thyroid diseases. Compared to PTC, the level of lead was significantly higher in TA, and lower in NG (p < 0.05). This difference remained significant in females when stratified by sex. Serum lead was negatively correlated with TSH (r_s =  - 0.27, p < 0.05) in PTC group. T3 was positively related to lead at quartile4 (r_s = 0.61, p < 0.05) in PTC group. No significant correlations were observed between lead and FT3 or FT4 in any group. The results suggested that lead might have different etiological roles in these three thyroid diseases.

Circular RNAs and thyroid cancer: closed molecules, open possibilities

Thyroid neoplasms requiring differential diagnosis between thyroid cancer and benign tumors can be detected in more than half of the healthy population. A generally accepted method that allows assessing the risk of malignant potential and determining the indications for surgical treatment of thyroid tumor is a fine-needle aspiration biopsy followed by a cytological examination. Nevertheless, in patients with indeterminate categories of cytological conclusions according to Bethesda system, the positive predictive value of the cytology result is significantly lower than desired and often leads to unjustified surgical treatment. In this regard, the search for alternative diagnostic solutions continues. Circular RNAs are a group of non-coding RNAs distinguished by a closed structure formed by covalent bonding of the nucleotide chain ends. Recent studies allow us to conclude that many different circular RNAs are involved in processes mediating oncogenesis in the thyroid gland, and their altered expression in tissue, blood, and exosomes of plasma may be a characteristic sign of thyroid cancer and certain clinicopathological features of its course. The purpose of this review is to analyze the accumulated data on the association of various circular RNAs with thyroid cancer and to discuss possible ways to improve the diagnosis and treatment of the disease based on the assessment of the expression of these molecules.

Plasma ω-3 and ω-6 fatty acids in thyroid diseases

The incidences of nodular goiter (NG), thyroid adenoma (TA), and thyroid cancer (TC) are increasing rapidly; however, the etiologies of these diseases remain unclear. The present study aimed to evaluate the differences in plasma fatty acids among these three thyroid diseases to facilitate etiological research. Four ω-3 and seven ω-6 polyunsaturated fatty acids were measured from 97 TC, 14 TA and 11 NG patient plasma samples with gas chromatography-flame ionization detector. Fatty acids levels were expressed as the percentage of each fatty acid out of the total fatty acids evaluated. The present study identified that the level of 22:6n-3 [median, interquartile range (IQR)] was significantly increased in TA (5.2%, 4.3-6.4%) compared with NG (3.6%, 3.1-4.6%) and TC patients (4.2%, 3.2-4.8%). Though not statistically significant, the levels of 20:5n-3 and 22:5n-3 demonstrated a similar pattern. The level of 22:4n-6 expressed (median, IQR) was significantly increased in NG patients (0.21%, 0.18-0.26%) compared with TA (0.16%, 0.15-0.18%) and TC (0.17%, 0.14-0.22%) patients. Furthermore the fatty acids 18:3n-6, 20:2n-6, 20:3n-6, 20:4:6, and 22:5n-6 demonstrated a similar but statistically insignificant pattern. This suggests that different fatty acids exhibit various etiological roles in NG, TA and TC and warrant further study.

Esophageal cancer associated with right aortic arch and thyroid adenoma

A 55-year-old Chinese woman with thoracic esophageal cancer associated with right aortic arch and thyroid adenoma was admitted to our hospital. Computed tomography revealed a right aortic arch with mirror-image branching and a mass in the esophagus. The following barium-coated esophagograms and esophagoscopy showed an ulcerative and infiltrative tumor in the upper thoracic esophagus. The patient also had an almost 10-year history of thyroid adenoma.

The Difference in Thyroid Stimulating Hormone Levels between Differentiated Carcinoma and Benign Enlargement

Introduction  Papillary and follicular thyroid carcinoma are common head and neck cancers. This cancer expresses a thyroid stimulating hormone (TSH) receptor that plays a role as a cancer stimulant substance. This hormone has a diagnostic value in the management of thyroid carcinoma. Objective  The present study aimed to determine the difference in TSH levels between differentiated thyroid carcinoma and benign thyroid enlargement. Methods  The present research design was a case-control study. The subjects were patients with thyroid enlargement who underwent thyroidectomies at the Dr. Sardjito General Hospital, Yogyakarta, Indonesia. Thyroid stimulating hormone levels were measured before the thyroidectomies. The inclusion criteria for the case group were: 1) differentiated thyroid carcinoma, and 2) complete data; while the inclusion criteria for the control group were: 1) benign thyroid enlargement, and 2) complete data. The exclusion criteria for both groups were: 1) patients suffering from thyroid hormone disorders requiring therapy before thyroidectomy surgery, 2) patients receiving thyroid suppression therapy before the thyroidectomy was performed, and 3) patients suffering from severe chronic diseases such as renal insufficiency, and severe liver disease. Results  There were 40 post-thyroidectomy case group patients and 40 post-thyroidectomy control group patients. There were statistically significant differences in TSH levels between the groups with differentiated thyroid carcinoma and benign thyroid enlargement ( p  = 0.001; odds ratio [OR] = 8.42; 95% confidence interval [CI]: 3.19-36.50). Conclusion  Based on these results, it can be concluded that there were significant differences in TSH levels between the groups with differentiated thyroid carcinoma and benign thyroid enlargement.

Pathological and Immunohistochemical Characterization of Thyroid Neoplasms in Cats

There are few pathological and immunohistochemical descriptions of thyroid neoplasms in cats. We investigated neoplasms of the thyroid in 31 cats (average age 15.6 years) in Southern Brazil. Most (96.8%) of these cases were classified as follicular adenomas and were predominantly unilateral and multinodular. Histologically, macrofollicular adenomas were the most common type observed. Carcinomas represented 3.2% of the investigated tumours. By immunohistochemical labelling, thyroglobulin was expressed more commonly than paired box gene 8 or thyroid transcription factor 1 in the follicular adenomas. One carcinoma was immunopositive for thyroglobulin, pancytokeratin, chromogranin A and synaptophysin, suggestive of a calcitonin-negative neuroendocrine carcinoma.

BRAFV600E mutation in the wrong place: a case of concomitant polycythemia vera, hairy cell leukemia, and thyroid adenoma

BACKGROUND

Polycythemia vera (PV) is one of the Philadelphia-negative myeloproliferative neoplasms (MPN), characterized by a pan-myelosis with an erythroid-predominant proliferation mainly driven by somatic JAK2V617F gain-of-function mutation. Hairy cell leukemia (HCL) is a rare B-cell lineage lymphoproliferative disease (LPD) with a typic immunophenotypic profile. BRAFV600E, leading to constitutive activation of the RAF/MEK/ERK signalling pathway and increased cell proliferation, is identified as the driver mutation in almost all cases. Although the risk of developing an LPD is significantly increased in patients with MPN compared with the general population, few cases of co-occurring PV and HCL are reported to date. BRAF is one of the most frequently mutated oncogenes in human cancer and some point mutations were identified in multiple neoplasms in addition to HCL, including follicular and papillary thyroid adenoma and carcinoma.

CASE PRESENTATION

Here we report a molecular diagnostic challenge in a woman with a concomitant diagnosis of JAK2V617F PV, BRAFV600E HCL, and HRASQ61K thyroid follicular adenoma.

CONCLUSION

In the age of molecular and precision medicine, this case underlines the importance of integrating molecular results with clinical, radiologic, cytologic, and histopathologic investigations.

Human papillomavirus and Epstein-Barr virus infection in benign thyroid lesions

INTRODUCTION

The objective was to investigate the correlation between Epstein-Barr virus (EBV) and human papillomavirus (HPV) infection in the development of benign thyroid lesions.

MATERIAL AND METHODS

29 cases of Hashimoto's thyroiditis (HT), 133 cases of thyroid adenoma, and 34 cases of HT with thyroid adenoma paraffin embedded tissue samples were used for EBV and HPV quantitative detection.

RESULTS

None of the tissue samples carried HPV DNA. In HT tissue samples, the positive rate of EBV was 55.2% (16/29). In thyroid adenoma tissue samples, the positive rate was 37.6% (50/133). In HT combined with thyroid adenoma tissue samples, the positive rate of EBV was 67.6% (23/34). There was no correlation between EBV infection and clinical features such as age and gender.

CONCLUSION

The occurrence and development of benign thyroid lesions are closely related to EBV infection. HT combined with thyroid adenoma may be more susceptible to EBV infection than simple HT and thyroid adenoma, which provides a new idea for the diagnosis and treatment of benign thyroid lesions.

Common Key Genes in Differentiating Parathyroid Adenoma From Thyroid Adenoma

Recent studies have demonstrated the close relationship between parathyroid adenoma (PA) and thyroid follicular adenoma (FTA). However, the underlying pathogenesis remains unknown. This study focused on exploring common pathogenic genes, as well as the pathogenesis of these two diseases, through bioinformatics methods. This work obtained PA and FTA datasets from the Integrated Gene Expression Database to identify the common differentially expressed genes (DEGs) of two diseases. The functions of the genes were investigated by GO and KEGG enrichment. The program CytoHubba was used to select the hub genes, while receiver operating characteristic curves were plotted to evaluate the predictive significance of the hub genes. The DGIbd database was used to identify gene-targeted drugs. This work detected a total of 77 DEGs. Enrichment analysis demonstrated that DEGs had activities of 3',5'-cyclic AMP, and nucleotide phosphodiesterases and were associated with cell proliferation. NOS1, VWF, TGFBR2, CAV1, and MAPK1 were identified as hub genes after verification. The area under the curve of PA and FTA was>0.7, and the hub genes participated in the Relaxin Signaling Pathway, focal adhesion, and other pathways. The construction of the mRNA-miRNA interaction network yielded 11 important miRNAs, while gene-targeting drug prediction identified four targeted drugs with possible effects. This bioinformatics study demonstrated that cell proliferation and tumor suppression and the hub genes co-occurring in PA and FTA, have important effects on the occurrence and progression of two diseases, which make them potential diagnostic biomarkers and therapeutic targets.

Classification of Thyroid Tumors Based on DNA Methylation Patterns

Background: Alterations in DNA methylation are stable epigenetic events that can serve as clinical biomarkers. The aim of this study was to analyze methylation patterns among various follicular cell-derived thyroid neoplasms to identify disease subtypes and help understand and classify thyroid tumors. Methods: We employed an unsupervised machine learning method for class discovery to search for distinct methylation patterns among various thyroid neoplasms. Our algorithm was not provided with any clinical or pathological information, relying exclusively on DNA methylation data to classify samples. We analyzed 810 thyroid samples (n = 256 for discovery and n = 554 for validation), including benign and malignant tumors, as well as normal thyroid tissue. Results: Our unsupervised algorithm identified that samples could be classified into three subtypes based solely on their methylation profile. These methylation subtypes were strongly associated with histological diagnosis (p < 0.001) and were therefore named normal-like, follicular-like, and papillary thyroid carcinoma (PTC)-like. Follicular adenomas, follicular carcinomas, oncocytic adenomas, and oncocytic carcinomas clustered together forming the follicular-like methylation subtype. Conversely, classic papillary thyroid carcinomas (cPTC) and tall cell PTC clustered together forming the PTC-like subtype. These methylation subtypes were also strongly associated with genomic drivers: 98.7% BRAFV600E-driven cancers were PTC like, whereas 96.0% RAS-driven cancers had a follicular-like methylation pattern. Interestingly, unlike other diagnoses, follicular variant PTC (FVPTC) samples were split into two methylation clusters (follicular like and PTC like), indicating a heterogeneous group likely to be formed by two distinct diseases. FVPTC samples with a follicular-like methylation pattern were enriched for RAS mutations (36.4% vs. 8.0%; p < 0.001), whereas FVPTC- with PTC-like methylation patterns were enriched for BRAFV600E mutations (52.0% vs. 0%, Fisher exact p = 0.004) and RET fusions (16.0% vs. 0%, Fisher exact p = 0.003). Conclusions: Our data provide novel insights into the epigenetic alterations of thyroid tumors. Since our classification method relies on a fully unsupervised machine learning approach for subtype discovery, our results offer a robust background to support the classification of thyroid neoplasms based on methylation patterns.

A thyroid adenoma in a pubertal male with thyroxine-binding globulin deficiency

Complete deficiency of thyroxin-binding globulin (TBG-CD) is not commonly associated with clinical symptoms, and little is known about thyroid tumors associated with TBG-CD. We present a case report of an asymptomatic follicular adenoma that spontaneously shrank in a patient with TBG-CD. A previously healthy 13-yr-old male presented with a diffusely swollen thyroid gland. Thyroid function tests revealed low total thyroxin and TBG concentrations, indicating a TBG deficiency. Ultrasonography revealed a mildly swollen thyroid gland with a nodule (14 × 12 × 19 mm) in the left lobe. Genetic analysis of peripheral blood revealed a previously reported SERPINA7 variant, which resulted in complete loss of TBG function. The nodule was identified as a follicular adenoma using fine-needle aspiration. Subsequently, the adenoma shrank without treatment. This pubertal case suggests that careful observation with ultrasonography is warranted for follicular adenoma in patients with TBG deficiency and that treatment may not be required.

Immune cells in thyroid adenoma and carcinoma: uncovering a hidden value of assessing tumor-host interplay and its potential application in thyroid cytopathology

Introduction

Although the role of tumor immune microenvironment (TIME) in thyroid cancer is well established, little data exists about the differences in immune cell presence in thyroid adenomas and carcinomas. We assume that immune cell density could be an additional diagnostic criterion for differentiating benign and malignant tumors in thyroid aspirates.

Aim

The current study compared the immune contexture of thyroid adenoma (TA) and thyroid carcinoma (TC) in histological and cytological specimens of III-V categories.

Materials and methods

This pilot study included 72 cases (36 of TA and 36 of TC) with verified histological diagnosis and pre-operative cytology corresponding to categories III, IV and V according to the Bethesda system for reporting thyroid cytology. The number of CD8+, CD68+ and CD163+ cells was assessed in histological samples of TA and TC with further comparison to cytological specimens. Besides, the expression of STAT6 and SMAD4 as potential regulators of TIME was evaluated in the study.

Results

TC demonstrated an immune-rich profile representing abundant tumor-associated CD8+ lymphocytes, CD68 and CD163+ macrophages. In contrast, TA represented mostly a low immune cell infiltration. The higher immunogenicity of TC was accompanied by the more profound expression of STAT6 and SMAD4 in tumor cells. The number of immune cells in cytological specimens correlated with CD8+ (r = 0.693; p < 0.001) and CD163+ cells (r = 0.559; p < 0.001) in histological samples, reflecting the differences in the tumor immune microenvironment between benign and malignant thyroid neoplasms.

Conclusion

TC demonstrated high immunogenicity compared to TA, which correlated to the number of immune cells in cytological specimens. The number of immune cells in thyroid cytology samples could be an additional criterion in cytological diagnostics for III-V Bethesda categories. Further investigations are needed to validate the findings of the study.

Synchronous Breast Carcinoma, Uterine Myoma, and Ovarian Teratoma in a Single Woman

Multiple primary tumors in a patient diagnosed with invasive ductal breast cancer are rarely reported in the literature. Here we present a case of invasive ductal carcinoma of the breast in a 42-year-old lady, with synchronous uterine leiomyoma (UL), ovarian teratoma and with prior history of follicular adenoma of thyroid in the same patient. The clinical presentation and management plan is discussed with a review of the literature. Breast cancer is the most common cancer in women where the concomitant occurrence of multiple primary tumors is a diagnostic and therapeutic challenge. In low- and middle-income countries, where facilities of genetic screening in all patients of synchronous neoplasia are limited due to scarcity of resources, strong clinical suspicion, multidisciplinary management, and follow-up remain important.

Pseudo-pheochromocytoma due to obstructive sleep apnea: a case report

SUMMARY

Obstructive sleep apnea (OSA) is a condition of intermittent nocturnal upper airway obstruction. OSA increases sympathetic drive which may result in clinical and biochemical features suggestive of pheochromocytoma. We present the case of a 65-year-old male with a 2.9-cm left adrenal incidentaloma on CT, hypertension, symptoms of headache, anxiety and diaphoresis, and persistently elevated 24-h urine norepinephrine (initially 818 nmol/day (89-470)) and normetanephrine (initially 11.2 µmol/day (0.6-2.7)). He was started on prazosin and underwent left adrenalectomy. Pathology revealed an adrenal corticoadenoma with no evidence of pheochromocytoma. Over the next 2 years, urine norepinephrine and normetanephrine remained significantly elevated with no MIBG avid disease. Years later, he was diagnosed with severe OSA and treated with continuous positive airway pressure. Urine testing done once OSA was well controlled revealed complete normalization of urine norepinephrine and normetanephrine with substantial symptom improvement. It was concluded that the patient never had a pheochromocytoma but rather an adrenal adenoma with biochemistry and symptoms suggestive of pheochromocytoma due to untreated severe OSA. Pseudo-pheochromocytoma is a rare presentation of OSA and should be considered on the differential of elevated urine catecholamines and metanephrines in the right clinical setting.

LEARNING POINTS

Obstructive sleep apnea (OSA) is a common condition among adults. OSA may rarely present as pseudo-pheochromocytoma with symptoms of pallor, palpitations, perspiration, headache, or anxiety. OSA should be considered on the differential of elevated urine catecholamines and metanephrines, especially in patients with negative metaiodobenzylguanidine (MIBG) scan results.