Neuroimages and Neuropathology of a Stroke-Like Cerebral Lymphomatoid Granulomatosis.

A 70-year-old man presented to the Emergency Department reporting the acute onset of non-fluent aphasia, hyposthenia, and hemi-anesthesia of the right body. Brain computerized tomography revealed a subcortical hypodense lesion in the middle cerebral artery territory. Neck ultrasounds of internal and external carotid arteries and of the vertebral arteries showed a focal moderate stenosis of the left internal carotid artery due to a soft atheromasic plaque. These findings that were initially consistent with a diagnosis of an ischemic stroke were not confirmed by magnetic resonance (MR). The latter showed an hyperintense lesion on FLAIR and T2-weighted sequences located in the left centrum semiovale, corona radiata, and thalamus, with a well-defined regular rim and a mild compressive effect on the lateral ventricle, with diffusivity restriction but without ADC reduction and with a punctate and serpiginous gadolinium enhancement on T1 sequences (Figure 1). Within the first day of observation, the patient started complaining progressive mental deterioration, in absence of any other possible causes, and a total body CT scan excluded any other organ involvement. Patient was then referred to the neurosurgeon in order to perform a brain biopsy. The neuropathology was compatible with the diagnosis of cerebral lymphomatoid granulomatosis (LG) (Figure 1).

Description of a new biosafe procedure for cytological specimens from patients with COVID-19 processed by liquid-based preparations.

BACKGROUND: Coronavirus disease 2019 is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and represents the causative agent of a potentially fatal disease. The spread of the infection and the severe clinical disease have led to the widespread adoption of social distancing measures. Special attention and efforts to protect or reduce transmission have been applied at all social levels, including health care operators. Hence, this reports focuses on the description of a new protocol for the safe management of cytological samples processed by liquid-based cytology (LBC) with an evaluation of the changes in terms of morphology and immunoreactivity. METHODS: From March 11 to April 25, 2020, 414 cytological cases suspicious for SARS-CoV-2 were processed with a new virus-inactivating method suggested by Hologic, Inc, for all LBC specimens. RESULTS: The samples showed an increased amount of fibrin in the background. A slight decrease in cellular size was also observed in comparison with the standard method of preparation. Nonetheless, the nuclear details of the neoplastic cells were well identified, and the immunoreactivity of the majority of those cells was maintained. The cell blocks did not show significant differences in morphology, immunoreactivity, or nucleic acid stability. CONCLUSIONS: Despite some minor changes in the morphology of the cells, the results of this study highlight that the adoption of the new protocol for the biosafety of LBC-processed samples in pathology laboratories is important for minimizing the risk for personnel, trainees, and cytopathologists without impairing the diagnostic efficacy of the technique.

Relevance of rosette patterns in variants of papillary thyroid carcinoma.

INTRODUCTION: The detection of rosette-like clusters (RLC) of follicular cells in thyroid carcinoma has been reported mostly in the columnar cell variant of papillary thyroid carcinoma (PTC). Despite the fact that diagnosing variants of PTC is no longer encouraged by The Bethesda System for Reporting Thyroid Cytopathology, the identification of cytomorphological features such as RLC linked with these tumours might help reduce possible misinterpretation in thyroid fine needle aspiration (FNA) cytology. We accordingly investigated the potential correlation of architectural patterns including RLC with PTC variants. METHODS: We analysed 225 thyroid FNA cytology cases diagnosed as suspicious for malignancy (SFM) and positive for malignancy (M) over a 1-year time where all samples had corresponding histology. We also included 150 benign lesions from the same period. The presence of RLC vs similar appearing solid clusters, papillary structures and microfollicles were evaluated. We also performed immunocytochemistry and molecular testing for BRAFV600E. RESULTS: We included 100 (44.4%) SFM favouring PTC and 125 (55.6%) M cases with cyto-histological correlation. On histology, all SFM and M cases showed malignancy including 140 (62.2%) classic PTC and 85 (37.8%) PTC variants. The cytomorphological patterns in all FNA samples included solid (74%), papillary (89%), microfollicular (70%), and pseudo-RLC morphology (25.7%). We identified only pseudo-RLC in 33 FNA specimens from PTC variant cases that included tall cell variant (42.4%), hobnail variant (21.2%) and miscellaneous variants (36.3%) of PTC. No definitive RLC were detected in our series. Immunocytochemistry and BRAFV600E were not specifically linked with an RLC pattern. CONCLUSIONS: These findings demonstrate that in our dataset the architectural pattern of RLC was not recognised within PTC variants. However, we did identify a pseudo-RLC pattern that was observed in association with tall cell variant and hobnail variant cases of PTC.

Analytical validation of a novel targeted next-generation sequencing assay for mutation detection in thyroid nodule aspirates and tissue.

PURPOSE: The identification of somatic mutations in cancer specimens enables detection of molecular markers for personalized treatment. We recently developed a novel molecular assay and evaluated its clinical performance as an ancillary molecular method for indeterminate thyroid nodule cytology. Herein we describe the analytical validation of the novel targeted next-generation sequencing (NGS) assay in thyroid samples from different sources. METHODS: We present validation data of a novel NGS-based panel on 463 thyroid samples, including 310 fine-needle aspiration (FNA) specimens from different sources (FNA collected in preservative solution, liquid-based, and stained smears), 10 fresh frozen, and 143 formalin-fixed paraffin-embedded (FFPE) thyroid tissue specimens. Sequencing performance in the different samples was evaluated along with reproducibility, repeatability, minimum nucleic acid input to detect variants, and analytical sensitivity of the assay. RESULTS: All thyroid samples achieved high sequencing performance, with a mean base coverage depth ranging from 2228 × (in liquid-based FNA) to 3661 × (in FNA stained smears), and coverage uniformity ranging from 86% (in FFPE) to 95% (in FNA collected in preservative solution), with all target regions covered above the minimum depth required to call a variant (500×). The minimum nucleic acid input was 1 ng. Analytic sensitivity for mutation detection was 2-5% mutant allele frequency. CONCLUSIONS: This validation study of a novel NGS-based assay for thyroid nodules demonstrated that the assay can be reliably used on multiple thyroid sample types, including FNA from different sources and FF and FFPE thyroid samples, thus providing a robust and reliable assay to genotype thyroid nodules, which may improve thyroid cancer diagnosis and care.

Performance of a dual-component molecular assay in cytologically indeterminate thyroid nodules.

PURPOSE: Deciding whether patients with a cytologically indeterminate thyroid nodule should be referred for surgery or for active surveillance is an important challenge for clinicians. The aim of this study was to evaluate the performance of a novel dual-component molecular assay as an ancillary molecular method for resolving indeterminate thyroid nodule cytology. METHODS: We selected 156 thyroid nodules from those that had undergone fine-needle aspiration processed by liquid-based cytology and surgical resection between June 2016 and December 2017. The sample set included 63 nodules cytologically classified as indeterminate, and 93 other nodules randomly selected from those with non-diagnostic, benign, suspicious, or malignant cytology. Nucleic acids from each nodule were subjected to next-generation sequencing analysis for mutation detection in 23 genes and to digital polymerase chain reaction (PCR) evaluation for miR-146b-5p expression levels. RESULTS: Used alone, mutation analysis in the indeterminate subset (cancer prevalence: 22.5%) displayed high sensitivity (89%) and NPV (96%). In contrast, the miR-146b-5p assay offered high specificity (93%) and PPV (93%). Combined use of both analyses improved panel performance by eliminating false-negative results. CONCLUSIONS: These preliminary data suggest that a dual-component molecular test can increase the diagnostic accuracy of thyroid cytology alone by reducing the number of nodules that will be classified as indeterminate and increasing those that can be reliably classified as benign. If these findings are confirmed, this test can be considered for use in clinical practice and is expected to reduce diagnostic surgery and health care costs, and to improve patient quality of life.

The immunocytochemical expression of VE-1 (BRAF V600E-related) antibody identifies the aggressive variants of papillary thyroid carcinoma on liquid-based cytology.

BACKGROUND: The recently introduced monoclonal V600E antibody (clone VE1) is likely to be an alternative strategy for detecting this mutation in thyroid lesions. Although VE1 immunostaining and molecular methods used to assess papillary thyroid carcinoma in surgical specimens are in good agreement, evaluation of VE1 in cytology and cell block samples is rarely performed, and its diagnostic value in cytology has not been well established. In this study, we sought to determine if VE1 is suitable for fine needle aspiration (FNA) and cell block methods. METHODS: A total of 86 patients who had BRAF V600E mutations were investigated with molecular and immunocytochemical (ICC) analysis in 45 FNA and 41 cell blocks. In total, 83 (96.5%) patients underwent surgical treatment. Assessment of BRAF V600E mutation status was performed in 72 (83.7%) cases. RESULTS: Among the 72 cases analysed, 54 cases agreed (ICC+/BRAF+ or ICC-/BRAF-), seven cases were false positive (ICC+/BRAF-) and 11 cases were false negative (ICC-/BRAF+). False negative cases were not detected in the cell block method. The statistical analysis showed that sensitivity and specificity of ICC for detecting the BRAF V600E mutation were 61% and 77% in FNA samples and 100% and 73% in cell block. CONCLUSION: The use of antibody VE-1 is a reliable method and a negative result of VE1 immunostaining might help to save time and money, restricting the molecular test to antibody-positive cases only. The identification of the aggressive variants of papillary carcinoma might be enabled by the expression of the antibody in neoplastic cells with tall cell features.

Cytologic Diagnosis of Oncocytic Neoplasms of the Thyroid Gland: The Importance of the Clinical Scenario.

It is a diagnostic challenge to differentiate benign and malignant thyroid neoplasms made up of Hürthle (or oncocytic) cells on cytologic material. They are large, polygonal cells with marked eosinophilic, granular cytoplasm reflective of overly abundant mitochondria. These cells commonly occur in nodular goiters and dominant adenomatous or hyperplastic nodules though they may also be the predominant component of neoplastic lesions. There are significant controversies concerning the optimal management of patients with oncocytic cell carcinoma. This review provides an overview of the most significant studies addressing the distinction between benign and malignant Hürthle cell lesions on cytology and histology.

RUNX3 as a Potential Predictor of Metastasis in Human Pancreatic Cancer.

BACKGROUND/AIM: In genetically engineered murine models of pancreatic ductal adenocarcinomas (PDAC), high levels of Runx3 increase the metastatic potential of cancer cells. In this study we evaluated the role of Runx3 in human pancreatic cancer. MATERIALS AND METHODS: Runx3 was retrospectively assessed by immunohistochemistry in seventy-eight tumor samples of patients who underwent surgical resection for PDCA and were followed at least for 24 months. RESULTS: Thirty-two cases resulted completely negative for Runx3; forty-six showed highly variable expression. We established an optimal cut-off value of Runx3 in predicting distant metastasis equal to 0.04. The odds ratio (ORs) for development of distant metastases at multivariate analysis for patients having Runx3 ≥0.04 was 4.26 (p=0.043) and 4.68 (p=0.032) after adjusting for residual tumor and treatment, respectively; OR for development of metastases in multiple sites was 4.28 (p=0.025) for Runx3 ≥0.04. CONCLUSION: Our results support the ability of Runx3 to contribute to the dissemination of human PDAC thus confirming the observations from murine models.

Diagnosis and Treatment of Metastases to the Thyroid Gland: a Meta-Analysis.

The thyroid is a rare site of clinically detectable tumor metastases; even though the gland is a highly vascularized structure, the frequency of metastases in the routine practice is less than 0.2% of all thyroid malignancies. The purpose of our meta-analysis is to evaluate the frequency of metastatic diffusion from other primary tumors to the thyroid gland and to suggest the best possible treatment through an evidence-based study. Relevant studies were identified by searching the following databases: PubMed, Scopus, and Web of Science. We selected all English-written articles published from 1995 to 2015. Studies were considered eligible if they reported the timing of metastatic spread and the site of the primary tumor in respect to the diaphragmatic region. Case reports were not included. Twenty-eight studies accounted for 514 patients. The rate of metachronous metastases was 69%. Fifty-three percent of primaries originated from the infradiaphragmatic region. Fine needle aspiration biopsy (FNAB) was done in 154 patients and 195 patients were treated mostly with surgery. A prevalence of primary tumors from the infradiaphragmatic region and of metachronous metastases was observed. Knowledge of the clinical history and the ancillary techniques can improve the sensitivity and accuracy of FNAB. Thyroidectomy may be considered a more effective treatment than radio-chemotherapy.

Molecular status of PI3KCA, KRAS and BRAF in ovarian clear cell carcinoma: an analysis of 63 patients.

AIMS: To evaluate the incidence of PI3KCA, KRAS and BRAF mutations in primary ovarian clear cell carcinoma (OCCC). METHODS: 63 consecutive patients, with a proven diagnosis of OCCC, according to WHO criteria, were included into the study. Pyrosequencing analysis of all three genes hotspot regions were performed on 2.5 µm sections of formalin-fixed paraffin-embedded tissue from primary OCCC. RESULTS: PI3KCA mutations were found in 20/63 (32%) cases; KRAS mutations were found in 8/63 (13%); no BRAF V600 mutations were found. In particular, 12/20 mutations (60%) of PI3KCA were found in the exon 20, whereas the remaining eight cases presented mutations in exon 9 (8/20; 40%). KRAS pyrosequencing analysis revealed higher incidence of codon 12 mutations (7/8; 90%) than codon 13 mutations (1/8; 10%). In five cases (5/66; 8%), synchronous mutations, affecting PI3KCA and KRAS genes, were found. No differences were found in the distribution of hotspot mutations, according to the stage. CONCLUSIONS: The high frequency of PI3KCA mutations, the low rate of mutations in KRAS and the absence of mutations in BRAF, indicate a molecular signature of OCCCs different from other ovarian carcinomas. Detection of driver mutations, such as PI3KCA and KRAS, may be the basis for a targeted therapy, although the clinical and therapeutic implications of these findings have to be supported by further studies.

A meta-analytic review of the Bethesda System for Reporting Thyroid Cytopathology: Has the rate of malignancy in indeterminate lesions been underestimated?

BACKGROUND: The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC) provides a 6-tier diagnostic framework using uniform criteria in reports of thyroid aspirates. One of the major advantages of this framework is its association with defined risks of malignancy, allowing standardized management algorithms for each diagnosis. The objective of the current meta-analysis was to demonstrate the feasibility of using TBSRTC among specimens in the atypia of undetermined significance or follicular lesion of undetermined significance (AUS/FLUS) and follicular neoplasm or suspicious for neoplasm (FN/SFN) categories. The authors also evaluated both the morphologic features and the risk of malignancy in the presence of Hurthle cells. METHODS: A literature search was performed of the PubMed, Scopus, and Web of Science databases for English-language studies published from January 2008 to December2014. Studies were considered eligible only if they evaluated the risk of malignancy for specimens in the AUS/FLUS and/or FN/SFN categories and included surgical follow-up. RESULTS: In total, 51 articles were identified that used TBSRTC criteria and provided data for a total of 145,928 fine-needle aspiration (FNA) specimens. Of these, FNAs that had surgical follow-up were selected among the AUS/FLUS (N = 4475) and FN/SFN (N = 3202) specimens. The overall rate of malignancy was 27% for the AUS/FLUS category and 31% for the FN/SFN category. CONCLUSIONS: The AUS category was characterized by limited reported follow-up and surgical outcome. The data demonstrated that FNAs with an AUS diagnosis had a higher risk of malignancy than the risk according to published TBSRTC criteria, whereas the percentage of malignancy in FNAs with an FN/SFN diagnosis did not differ from that according to TBSRTC. Hurthle cell lesions represent a challenging category, underlying the importance of further studies to define whether they can be diagnosed in the AUS/FLUS category rather than the FN/SFN category.

Dicer and Drosha expression and response to Bevacizumab-based therapy in advanced colorectal cancer patients.

PURPOSE: The miRNA-regulating enzymes Dicer and Drosha exhibit aberrant expression in several cancer types. Dicer and Drosha play a crucial role during the angiogenetic process in vitro and, for Dicer, in vivo. We aimed to investigate the potential role of Dicer and Drosha in predicting response to Bevacizumab-based therapy in advanced colorectal cancer (CRC) patients. METHODS: Dicer and Drosha mRNA levels were analysed in formalin-fixed paraffin-embedded specimens from patients affected by advanced CRC treated with or without Bevacizumab-containing regimens (n=116 and n=50, respectively) and from patients with diverticulosis as control group (n=20). The experimental data were obtained using qRT-PCR, analysed comparing Dicer and Drosha expression levels in tumour samples versus normal mucosa and then compared to clinical outcome. RESULTS: The tumour samples from Bevacizumab-treated patients showed a significantly higher Drosha expression (P<.001) versus normal mucosa, while Dicer levels did not differ. Intriguingly, we found that low Dicer levels predicted a longer progression-free survival (PFS) (P<.0001) and overall survival (OS) (P=.009). In addition, low Dicer levels were associated with better response to Bevacizumab-based treatments versus high Dicer levels (1.7% complete responses and 53.4% partial responses versus 0% and 32.7%, respectively; P=.0067). Multivariate analysis identified three independent predictors of improved OS: high performance status (PS) (relative risk (RR) 1.45; P=.011), lower organs involvement (RR 0.79; P=.034) and low Dicer expression (RR 0.71; P=.008). Conversely, Drosha levels were not associated with prognosis and outcome associated with treatment. In non-Bevacizumab-treated patients, Dicer and Drosha expression did not correlate with outcome. CONCLUSION: These findings suggest that low Dicer mRNA levels seem to be independent predictors of favourable outcome and response in patients affected by advanced CRCs treated with Bevacizumab-based therapy.