Follicular Thyroid Adenoma and Follicular Thyroid Carcinoma-A Common or Distinct Background? Loss of Heterozygosity in Comprehensive Microarray Study

Pre- and postsurgical differentiation between follicular thyroid adenoma (FTA) and follicular thyroid cancer (FTC) represents a significant diagnostic challenge. Furthermore, it remains unclear whether they share a common or distinct background and what the mechanisms underlying follicular thyroid lesions malignancy are. The study aimed to compare FTA and FTC by the comprehensive microarray and to identify recurrent regions of loss of heterozygosity (LOH). We analyzed formalin-fixed paraffin-embedded (FFPE) samples acquired from 32 Caucasian patients diagnosed with FTA (16) and FTC (16). We used the OncoScan™ microarray assay (Affymetrix, USA), using highly multiplexed molecular inversion probes for single nucleotide polymorphism (SNP). The total number of LOH was higher in FTC compared with FTA (18 vs. 15). The most common LOH present in 21 cases, in both FTA (10 cases) and FTC (11 cases), was 16p12.1, which encompasses many cancer-related genes, such as TP53, and was followed by 3p21.31. The only LOH present exclusively in FTA patients (56% vs. 0%) was 11p11.2-p11.12. The alteration which tended to be detected more often in FTC (6 vs. 1 in FTA) was 12q24.11-q24.13 overlapping FOXN4, MYL2, PTPN11 genes. FTA and FTC may share a common genetic background, even though differentiating rearrangements may also be detected.

High incidence of FLT3 mutations in follicular thyroid cancer: potential therapeutic target in patients with advanced disease stage

Background:

Conventional treatments for follicular thyroid cancer (FTC) can be ineffective, leading to poor prognosis. The aim of this study was to identify mutations associated with FTC that would serve as novel molecular markers of the disease and its outcome and could potentially identify new therapeutic targets.

Methods:

FLT3 mutations were first detected in a 29-year-old White female diagnosed with metastasized, treatment-refractory FTC. Analyses of FLT3 mutational status through next-generation sequencing of formalin-fixed, paraffin-embedded FTC specimens were subsequently performed in 35 randomly selected patients diagnosed with FTC.

Results:

FLT3 mutations were found in 69% of patients. FLT3 mutation-positive patients were significantly older than those that were FLT3 mutation-negative [median age at diagnosis 54 (36–82) versus 45 (27–58) (p = 0.023)]. Patients over 60 years were 23 times more likely to be FLT3 mutation-positive (p = 0.006). However, the number of FLT3 mutations did not correlate with age (r-Pearson: –0.244, p-value: 0.25). A total of 26 mutations were identified in the FLT3 gene with 2–16 FLT3 mutations in each FLT3 mutation-positive patient (mean: 5.6 mutations/patient). Tyrosine kinase domain (TKD) mutations in the FLT3 gene were detected in 58% of FLT3 mutation-positive patients. All FLT3 mutation-positive patients with a disease stage of pT2N1 or worse harbored at least one mutation in the TKD of FLT3.

Conclusions:

There is a wide spectrum and high frequency of FLT3 mutations in FTC. The precise role of FLT3 mutations in the genesis of FTC, as well as its potential role as a therapeutic target, requires further investigation.

Genetic heterogeneity of indeterminate thyroid nodules assessed preoperatively with next-generation sequencing reflects the diversity of the final histopathologic diagnosis

INTRODUCTION

Inconclusive cytologic results of thyroid fine‑needle aspiration biopsy (FNAB) include atypia or follicular lesion of undetermined significance (FLUS) and follicular neoplasm or suspicious for follicular neoplasm (SFN).

OBJECTIVES

We aimed to assess the genetic background of indeterminate thyroid nodules and to identify new genetic pathways potentially involved in the development of follicular thyroid cancer.

PATIENTS AND METHODS

Genomic DNA was isolated from FNAB samples from 25 white patients (2 men; 23 women) diagnosed preoperatively with FLUS (n = 16) and SFN (n = 9). Next‑generation sequencing (NGS) was performed. The results were compared with clinical data, including final postsurgical diagnoses.

RESULTS

The malignancy rate was 28%. KDR, RET, and TP53 gene mutations were most frequent in FLUS and SFN samples finally diagnosed as cancers, whereas alterations in RET, TP53, FLT3, APC, and PDGFRA predominated in benign tumors. KDR tended to be more common in malignant samples (75% vs 20%, P = 0.1). A total number of mutated genes was higher in patients with benign tumors (17 vs 11, P = 0.02), but there was no difference between groups in the mean number of mutations per patient (4.9 [range, 1-9]).

CONCLUSIONS

We showed that the heterogeneity in the genetic background of indeterminate thyroid nodules corresponds to their histopathologic diversity. The role of KDR as a possible malignancy marker needs to be confirmed. Glass slides with FNAB samples may constitute a reliable source of genetic material for NGS studies, providing a better insight into the molecular profile of thyroid nodules.

Klotho expression and nodal involvement as predictive factors for large cell lung carcinoma

INTRODUCTION

Klotho has been recently described as a carcinogenesis suppressor. Large cell neuroendocrine lung carcinoma (LCNEC) is a rare, highly malignant neoplasm. In the light of increasing incidence of neuroendocrine tumours, biomarkers predicting survival are needed. We consider that Klotho might be one.

MATERIAL AND METHODS

We analysed records of all patients diagnosed with LCNEC, atypical carcinoid and typical carcinoid operated on in our institution between 2007 and 2015. Initially, we found 134 cases. Forty-six specimens were unattainable and thus excluded from research. All patients diagnosed with LCNEC according to the WHO classification were included in the study. Immunohistochemical staining for Klotho was performed. We retrospectively reviewed patient charts and analysed multiple variables.

RESULTS

Positive staining for Klotho was present in 36 tissue specimens, while 12 patients were Klotho-negative. Survival length was significantly higher in Klotho-positive cases (p = 0.024), while advanced nodal status (N1 and N2) represented a marker of poor outcome (p = 0.011). In multivariate analysis, both Klotho presence (p = 0.015; HR = 0.37; 95% CI: 0.17-0.86) and nodal involvement (p = 0.007; HR = 3.04; 95% CI: 1.37-6.82) were independent prognostic factors. Tumour vessel invasion and visceral pleura infiltration were not associated with worse treatment results. Klotho presence predicted a favourable prognosis in these groups (p = 0.018; p = 0.007).

CONCLUSIONS

Our results suggest that Klotho might be a positive factor for predicting survival in LCNEC and nodal involvement a negative one. Thus, these two markers may assist in the selection of subjects with unfavourable prognosis and to personalise therapy regimens.

Differences in Mutational Profile between Follicular Thyroid Carcinoma and Follicular Thyroid Adenoma Identified Using Next Generation Sequencing

We aimed to identify differences in mutational status between follicular thyroid adenoma (FTA) and follicular thyroid cancer (FTC). The study included 35 patients with FTA and 35 with FTC. DNA was extracted from formalin-fixed paraffin-embedded (FFPE) samples from thyroidectomy. Next-generation sequencing (NGS) was performed with the 50-gene Ion AmpliSeq Cancer Hotspot Panel v2. Potentially pathogenic mutations were found in 14 (40%) FTA and 24 (69%) FTC patients (OR (95%CI) = 3.27 (1.22−8.75)). The number of mutations was higher in patients with FTC than FTA (p-value = 0.03). SMAD4 and STK11 mutations were present only in patients with FTA, while defects in FBXW7, JAK3, KIT, NRAS, PIK3CA, SMARCB1, and TP53 were detected exclusively in FTC patients. TP53 mutations increased the risk of FTC; OR (95%CI) = 29.24 (1.64–522.00); p-value = 0.001. FLT3-positivity was higher in FTC than in the FTA group (51.4% vs. 28.6%; p-value = 0.051). The presence of FLT3 and TP53 with no RET mutations increased FTC detectability by 17.1%, whereas the absence of FLT3 and TP53 with a presence of RET mutations increased FTA detectability by 5.7%. TP53 and FLT3 are candidate markers for detecting malignancy in follicular lesions. The best model to predict FTA and FTC may consist of FLT3, TP53, and RET mutations considered together.

Evaluation of 167 Gene Expression Classifier (GEC) and ThyroSeq v2 Diagnostic Accuracy in the Preoperative Assessment of Indeterminate Thyroid Nodules: Bivariate/HROC Meta-analysis

The objective of this meta-analysis was to evaluate the performance of the Gene Expression Classifier (GEC) and ThyroSeq v2 (ThyroSeq) in the preoperative diagnosis of thyroid nodules with indeterminate fine-needle aspiration biopsy results. We searched literature databases from January 2001 to April 2018. The bivariate model analysis was performed to estimate pooled sensitivity, specificity, positive likelihood ratio (LR+), negative likelihood ratio (LR-), positive predictive value (PPV), and negative predictive value (NPV). Pooled data from 1086 nodules with histopathologic confirmation from 16 GEC studies enabled calculation of diagnostic parameters (95% confidence interval): sensitivity 98% (96-99%), specificity 12% (8-20%), PPV 45% (37-53%), and NPV 91% (85-96%). Pooled data from five ThyroSeq studies assessing 459 nodules showed sensitivity of 84% (74-91%), specificity 78% (50-92%), PPV 58% (31-81%), and NPV 93% (89-97%). When both tools were compared, GEC had a significantly higher sensitivity (p = 0.003), while ThyroSeq had a significantly higher specificity (p < 0.001) and accuracy (p = 0.015). Pooled LR+ was higher for ThyroSeq: 3.79 (1.40-10.27) vs. 1.12 (1.05-1.20). Pooled LR- was higher for GEC, 0.20 (0.10-0.39) vs. 0.13 (0.05-0.31). The bivariate summary estimates of sensitivity and specificity for GEC and ThyroSeq and their pooled accuracy showed a superiority of the ThyroSeq test. The GEC with a high sensitivity and NPV may be helpful in ruling out malignancy in cases of indeterminate thyroid nodule cytology. ThyroSeq has a significantly higher specificity and accuracy with an acceptable sensitivity so that it has the potential for use as an all-round test of malignancy of thyroid nodules.

Correction to: Evaluation of 167 Gene Expression Classifier (GEC) and ThyroSeq v2 Diagnostic Accuracy in the Preoperative Assessment of Indeterminate Thyroid Nodules: Bivariate/HROC Meta-analysis

The original version of the article unfortunately contained an error.

The value of Fn14, CD44v, and EGFR expression in lung adenocarcinoma patients with and without activating EGFR gene mutation

e20514

Background: Lung cancer is considered the most common cause of death in the world. The prognosis for patients is poor and depends on the clinical stage and the histological type of cancer. There is a need to identify and develop new therapeutic targets that could improve the prognosis of NSCLC patients and may be responsible for development of resistance to TKI therapy. Increased expression of Fn14 or CD44v and EGFR was observed in many tumors and also correlated with the overall survival of NSCLC patients Methods: We analyzed the clinical data and the immunohistochemical expression of Fn14, CD44v and EGFR in tumor tissues from 61 patients with NSCLC divided in two groups according to the presence of activating EGFR gene mutation. The aim of the study was to evaluate the correlation between the expression of the studied molecules and the neoplastic disease course of NSCLC patients. Results: Increased expression of Fn14 was observed in study group (B) compared to expression of this molecule in the control group (K). There were no differences in the intensity of the reaction with anti CD44v and EGFR antibodies in both groups. OS was significantly longer in the study group. Histological grade of tumor correlated with the intensity of CD44v expression in both groups. There was no correlation between the OS and Fn14 expression in any group. Negative correlation was noted between the expression of CD44v and the OS in the study group and between EGFR expression and the OS in both groups. Conclusions: Our observations suggest that the expression of CD44v and EGFR may be useful clinical markers of prognostic value in lung adenocarcinoma patients regardless of the presence of activating mutation in EGFR gene. Simultaneous assessment of Cd44v and EGFR expression may grant a greater prognostic value than the assessment of each receptor separately. Increased expression of Fn14 receptor in patients with EGFR gene mutation may become a new target in therapy allowing to eliminate the problem of secondary resistance to treatment with TKI’s

Medullary thyroid carcinoma - PET/CT imaging with 68Ga-labelled gastrin and somatostatin analogues

CASE PRESENTATION

a 75-year-old man with a 10-year history of nodular goitre was referred for clinical evaluation. The ultrasound scan revealed enlarged thyroid right lobe almost fully filled with a heterogeneous nodule with numerous calcifications. Fine-needle aspiration biopsy suggested medullary thyroid carcinoma (MTC). Before the surgery the patient was referred to the nuclear medicine department and somatostatin receptor imaging (SRS; 68Ga-DOTATATE) with PET/CT was performed. The scan demonstrated an increased uptake within the right thyroid mass. Subsequent PET/CT with 68Ga-gastrin analogue (MG48) revealed the same indications as the SRS: an increased alveolar uptake in the right thyroid mass without the signs of lymph node metastases. The patient underwent total thyroidectomy and central lymph nodes dissection. Histopathology examination confirmed the presence of MTC with vascular invasion, but without lymph node metastases (pT3NoMx according to the 7th edition of the AJCC Cancer Staging Manual). Immunohistochemical staining revealed positive reaction to calcitonin and CD56, whereas the reaction to thyroglobulin remained negative. The Ki-67 was 1%. Staining for SSTR2 and CCK2 showed high cytoplasmic expression in both cases. Knowledge of the presence of CCK2 receptor in MTC patients may be an important indication for the choice of diagnostic and therapeutic procedures. The presence of both the receptor types, cholecystokinin-2/gastrin and somatostatin, is possibly an interesting combination as far as the therapeutic target is concerned.

Epithelioid angiomyolipoma mimicking adrenal cortical carcinoma: A diagnostic pitfall

Epithelioid angiomyolipoma (EAML) is a rare mesenchymal neoplasmic variant of angiomyolipoma characterized by aggressive growth and unpredictable outcome. Cases of local recurrence and distant metastasis have been described. The histopathological diagnosis may be difficult, as EAML often mimics other neoplasms. This is the case report of a 39-year-old male patient with EAML, which was initially diagnosed as adrenal cortical carcinoma, due to the lack of cooperation between clinicians and pathologists.

Incidental ¹⁸F-FDG uptake in the thyroid in patients diagnosed with PET/CT for other malignancies

BACKGROUND

The value of PET/CT imaging in diagnosis of different cancers has been widely described. PET/CT may contribute to visualization of additional findings that were not the indication to the study and did not refer to initial diagnosis. In a small number of PET/CT scans an incidentally found focal ¹⁸F-FDG uptake in the thyroid gland is found. The goal of the study was to estimate the prevalence and evaluate the clinical significance of incidental thyroid ¹⁸F-FDG uptake in a cohort of patients diagnosed for different malignancies.

MATERIAL AND METHODS

2478 PET/CT scans using ¹⁸F-FDG were performed in 1925 subjects for evaluation of different, non-thyroid malignancies. For PET/CT examination, a Discovery ST (General Electric) PET/CT scanner was used. Patients with focal ¹⁸F-FDG activity were further evaluated by means of fine needle aspiration biopsy (FNAB). If cytological examination disclosed malignancy or suspicion of malignancy, thyroidectomy was performed. Both cytological and histopathological results were then analyzed.

RESULTS

Focal increased ¹⁸F-FDG uptake was found in 71 patients (3.7%), and cytological or histopathological results were evaluable in 20 of them. In general, 8 cases of thyroid cancer were found, which accounts for 40% probability of malignancy. The predominant histopathological diagnosis was papillary thyroid carcinoma (5 out of 8 cases). Additionally, in one case (5%) thyroid metastasis of lung cancer was detected. Diffused ¹⁸F-FDG activity in both thyroid lobes was observed in 120 subjects (6.2%)--in most cases chronic thyroiditis was confirmed.

CONCLUSIONS

The probability of malignancy of focal thyroid incidentalomas in ¹⁸F-FDG PET/CT scans is rather high. Therefore, thorough evaluation of such lesions is highly recommended in each case. Most thyroid malignancies incidentally detected in PET/CT are papillary carcinomas.

[Nonchromaffinic paraganglioma (chemodectoma) of tympanic cavity]

Nonchromaffinic paraganglioma derives from neuroectoderma. It is characterised by plenty vascularisation. Histopathologically it is a benign tumor, and doesn't give any metastasis. Although because of localisation, vascularisation and possibility of bone destruction is clinically malignant. In this paper we present three cases of paraganglioma localised in tympanic cavity treated surgically.

Endoscopical and histological aspects of inflammatory changes in J-pouch mucosa

The aim of the study was endoscopic and histological evaluation of mucosal inflammatory changes in the ileal reservoir after restorative proctocolectomy with ileoanal anastomosis (IPAA) because of FAP (27 patients) and ulcerative colitis (34 patients). Endoscopic symptoms of pouchitis (edema, granularity, contact bleeding, loss of vascular pattern, mucus, erosions) were found in 13 patients (4 were operated on because of FAP, 9 because of UC). A statistically significant difference (p < 0.0001) was found between endoscopic inflammatory index in UC (4.0 +/- 0.5) and in FAP (1.00 +/- 0.00). The endoscopic changes were correlated with the Moskowitz histological classification, in 12 acute score and in 6 chronic score were above 4 points. In 18 patients histological diagnosis of pouchitis was made (5 in FAP, 13 in UC). Acute pouchitis occurred in 12 patients and chronic in 6. In one patient histological changes resembled Crohn's disease. Regular endoscopic control with histological examination and verification of inflammatory lesions in the ileal reservoir is necessary.

[Liposarcoma of the neck]

Liposarcoma is a malignant neoplasm of soft tissue. Its occurrence in the head and neck region is extremely rare. The case of a 26-year-old woman with neck liposarcoma is presented. The clinical manifestation, histopathology, possibility and results of the tumor treatment are described according to the literature.